PT J
AU FANJUL, A
   DAWSON, MI
   HOBBS, PD
   JONG, L
   CAMERON, JF
   HARLEV, E
   GRAUPNER, G
   LU, XP
   PFAHL, M
AF FANJUL, A
   DAWSON, MI
   HOBBS, PD
   JONG, L
   CAMERON, JF
   HARLEV, E
   GRAUPNER, G
   LU, XP
   PFAHL, M
TI A NEW CLASS OF RETINOIDS WITH SELECTIVE-INHIBITION OF AP-1 INHIBITS PROLIFERATION
SO NATURE
LA English
DT Article
ID acid receptor-alpha; isotretinoin; prevention; pathways; analogs; ligands; cancer
AB RETINOIDS regulate many biological processes, including differentiation, morphogenesis and cell proliferation(1-3). They are also important therapeutic agents, but their clinical usefulness is limited because of side effects(4-8). Retinoid activities are mediated by specific nuclear receptors, the RARs and RXRs, which can induce transcriptional activation through specific DNA sites(3,9-11) or by inhibiting the transcription factor AP-1 (refs 12-15), which usually mediates cell proliferation signals(16). Because the two types of receptor actions are mechanistically distinct(12,15) we investigated whether conformationally restricted retinoids, selective for each type of receptor action, could be identified, Here we describe a new class of retinoids that selectively inhibits AP-1 activity but does not activate transcription. These retinoids do not induce differentiation in F9 cells but inhibit effectively the proliferation of several tumour cell lines, and could thus serve as candidates for new retinoid therapeutic agents with reduced side effects.
C1 SRI INT,DIV LIFE SCI,MENLO PK,CA 94025.
   LA JOLLA CANC RES FDN,CTR CANC,LA JOLLA,CA 92037.
C3 SRI International; Sanford Burnham Prebys Medical Discovery Institute
NR 28
TC 324
Z9 352
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 107
EP 111
DI 10.1038/372107a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800084
PM 7969403
DA 2026-03-10
ER

PT J
AU BLACKDEN, B
AF BLACKDEN, B
TI THE USE OF TEMPORARY LABORATORY SCIENTISTS
SO NATURE
LA English
DT Article
C1 LABSTAFF,F-75003 PARIS,FRANCE.
RP BLACKDEN, B (corresponding author), LAB STAFF LTD,SLOUGH,BERKS,ENGLAND.
NR 2
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 689
EP 690
DI 10.1038/369689a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900066
DA 2026-03-10
ER

PT J
AU HARBURY, PB
   KIM, PS
   ALBER, T
AF HARBURY, PB
   KIM, PS
   ALBER, T
TI CRYSTAL-STRUCTURE OF AN ISOLEUCINE-ZIPPER TRIMER
SO NATURE
LA English
DT Article
ID alpha-fibrous proteins; helical coiled coils; gcn4 leucine-zipper; amino-acid sequence; hemagglutinin; refinement; glycoprotein; specificity; nucleotide; resolution
AB SUBUNIT oligomerization in many proteins is mediated by short coiled-coil motifs(1,2). These motifs share a characteristic seven-amino-acid repeat containing hydrophobic residues at the first (a) and fourth (d) positions. Despite this common pattern, different sequences form two-, three- and four-stranded helical ropes. We have investigated the basis for oligomer choice by characterizing variants(3) of the GCN4 lencine-zipper dimerization domain that adopt trimeric or tetrameric structures in response to mutations at the a and d positions. We now report the high-resolution X-ray crystal structure of an isoleucine-containing mutant that folds into a parallel three-stranded, alpha-helical coiled coil. In contrast to the dimer and tetramer structures(3,4), the interior packing of the trimer can accommodate beta-branched residues in the most preferred rotamer at both hydrophobic positions. Compatibility of the shape of the core amino acids with the distinct packing spaces in the two-, three- and four-stranded conformations appears to determine the oligomerization state of the GCN4 leucine-zipper variants.
C1 MIT,HOWARD HUGHES MED INST,WHITEHEAD INST,DEPT BIOL,CAMBRIDGE,MA 02142.
   UNIV CALIF BERKELEY,DEPT MOLEC & CELL BIOL,BERKELEY,CA 94720.
C3 Howard Hughes Medical Institute; Massachusetts Institute of Technology (MIT); Whitehead Institute; University of California System; University of California Berkeley
RP HARBURY, PB (corresponding author), HARVARD UNIV,SCH MED,DEPT BIOL CHEM & MOLEC PHARMACOL,BOSTON,MA 02115, USA.
NR 31
TC 437
Z9 553
U1 1
U2 53
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 80
EP 83
DI 10.1038/371080a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100056
PM 8072533
DA 2026-03-10
ER

PT J
AU BERGGREN, M
   INGANAS, O
   GUSTAFSSON, G
   RASMUSSON, J
   ANDERSSON, MR
   HJERTBERG, T
   WENNERSTROM, O
AF BERGGREN, M
   INGANAS, O
   GUSTAFSSON, G
   RASMUSSON, J
   ANDERSSON, MR
   HJERTBERG, T
   WENNERSTROM, O
TI LIGHT-EMITTING-DIODES WITH VARIABLE COLORS FROM POLYMER BLENDS
SO NATURE
LA English
DT Article
ID electroluminescent diodes; conjugated polymers; carrier confinement; efficiency; chain
AB THE range of materials now available for polymer-based light-emitting diodes (LEDs) is such that electroluminescence can be obtained throughout the visible spectrum(1-12). Here we show that, by blending polymers with different emission and charge-transport characteristics, LEDs can be fabricated in which the emission colour varies as a function of the operating voltage. This phenomenon arises from the self-organizing properties of the blends, in which entropy drives phase separation of the constituent polymers and gives rise to submicrometre-sized domains having a range of compositions and emission characteristics. Emission from domains of different composition is controlled by the ease with which charge is injected, which in turn depends on the applied voltage.
C1 CHALMERS UNIV TECHNOL,DEPT ORGAN CHEM,S-41296 GOTHENBURG,SWEDEN.
   CHALMERS UNIV TECHNOL,DEPT POLYMER TECHNOL,S-41296 GOTHENBURG,SWEDEN.
C3 Chalmers University of Technology; Chalmers University of Technology
RP BERGGREN, M (corresponding author), LINKOPING UNIV,APPL PHYS LAB,S-58183 LINKOPING,SWEDEN.
NR 23
TC 767
Z9 856
U1 0
U2 114
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 444
EP 446
DI 10.1038/372444a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200050
DA 2026-03-10
ER

PT J
AU OECHEL, WC
   COWLES, S
   GRULKE, N
   HASTINGS, SJ
   LAWRENCE, B
   PRUDHOMME, T
   RIECHERS, G
   STRAIN, B
   TISSUE, D
   VOURLITIS, G
AF OECHEL, WC
   COWLES, S
   GRULKE, N
   HASTINGS, SJ
   LAWRENCE, B
   PRUDHOMME, T
   RIECHERS, G
   STRAIN, B
   TISSUE, D
   VOURLITIS, G
TI TRANSIENT NATURE OF CO2 FERTILIZATION IN ARCTIC TUNDRA
SO NATURE
LA English
DT Article
ID atmospheric carbon-dioxide; transgenic tobacco plants; elevated co2; tussock tundra; climate change; photosynthetic acclimation; unmanaged ecosystems; biomass production; mineral-nutrition; soil-temperature
AB THERE has been much debate about the effect of increased atmospheric CO2 concentrations on plant net primary production(1,3) and on net ecosystem CO2 flux(3-10). Apparently conflicting experimental findings could be the result of differences in genetic potential(11-15) and resource availability(16-20), different experimental conditions(21-24) and the fact that many studies have focused on individual components of the system(2,21,25-27) rather than the whole ecosystem. Here we present results of an in situ experiment on the response of an intact native ecosystem to elevated CO2. An undisturbed patch of tussock tundra at Toolik Lake, Alaska, was enclosed in greenhouses in which the CO2 level, moisture and temperature could be controlled(28), and was subjected to ambient (340 p.p.m.) and elevated (680 p.p.m.) levels of CO2 and temperature (+4 degrees C). Air humidity, precipitation and soil water table were maintained at ambient control levels. For a doubled CO2 level alone, complete homeostasis of the CO2 flux was re-established within three Sears, whereas the regions exposed to a combination of higher temperatures and doubled CO2 showed persistent fertilization effect on net ecosystem carbon sequestration over this time. This difference may be due to enhanced sink activity from the direct effects of higher temperatures on growth(16,29-33) and to indirect effects from enhanced nutrient supply caused by increased mineralization(10,11,19,27,34). These results indicate that the responses of native ecosystems to elevated CO2 may not always be positive, and are unlikely to be straightforward. Clearly, CO2 fertilization effects must always be considered in the context of genetic limitation, resource availability and other such factors.
C1 SAN DIEGO STATE UNIV, SYST ECOL RES GRP, SAN DIEGO, CA 92182 USA.
   STANFORD UNIV, STANFORD HUMAN GENOME CTR, DEPT GENET, STANFORD, CA 94305 USA.
   US FOREST SERV, PACIFIC NW RES STN, FORESTRY SCI LAB, CORVALLIS, OR 97331 USA.
   NASA, GODDARD SPACE FLIGHT CTR, GREENBELT, MD 20771 USA.
   OMEGA MED SYST INC, RALEIGH, NC 27619 USA.
   UNIV CALIF RIVERSIDE, STATEWIDE AIR POLLUT RES CTR, RIVERSIDE, CA 92521 USA.
   DUKE UNIV, DEPT BOT, DURHAM, NC 27706 USA.
C3 California State University System; San Diego State University; Stanford University; United States Department of Agriculture (USDA); United States Forest Service; National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center; University of California System; University of California Riverside; Duke University
RP OECHEL, WC (corresponding author), SAN DIEGO STATE UNIV, GLOBAL CHANGE RES GRP, SAN DIEGO, CA 92182 USA.
NR 79
TC 189
Z9 205
U1 1
U2 77
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 500
EP 503
DI 10.1038/371500a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900050
DA 2026-03-10
ER

PT J
AU PRAGNELL, M
   DEWAARD, M
   MORI, Y
   TANABE, T
   SNUTCH, TP
   CAMPBELL, KP
AF PRAGNELL, M
   DEWAARD, M
   MORI, Y
   TANABE, T
   SNUTCH, TP
   CAMPBELL, KP
TI CALCIUM-CHANNEL BETA-SUBUNIT BINDS TO A CONSERVED MOTIF IN THE I-II CYTOPLASMIC LINKER OF THE ALPHA(1)-SUBUNIT
SO NATURE
LA English
DT Article
ID functional expression; skeletal-muscle; molecular-cloning; alpha-1 subunit; alpha-1-subunit; alpha-2-subunit
AB THE beta-subunit is an integral component of purified voltage-sensitive Ca2+ channels(1-3). Modulation of Ca2+ channel activity by the beta-subunit, which includes significant increases in transmembrane current and/or changes in kinetics, is observed on coexpression of six alpha(1)-subunit genes with four beta-subunit genes in all alpha(1)-beta combinations tested(4-12). Recent reports suggest that this regulation is not due to targeting of the alpha(1)-subunit to the plasma membrane but is probably a result of a conformational change induced by the beta-subunit(11,13). Here we report that the beta-subunit binds to the cytoplasmic linker between repeats I and II of the dihydropyridine-sensitive alpha(1)-subunits from skeletal (alpha(1S)) and cardiac muscles (alpha(1C-a)), and also with the more distantly related neuronal alpha(1A) and omega-conotoxin GVIA-sensitive alpha 1B-subunits. Sequence analysis of the beta-subunit binding site identifies a conserved motif (QQ-E--L-GY--WI---E) positioned 24 amino acids from the IS6 transmembrane domain in each alpha(1)-subunit. Mutations within this motif reduce the stimulation of peak currents by the beta-subunit and alter inactivation kinetics and voltage-dependence of activation. Conservation of the beta-subunit binding motif in these functonally distinct calcium channels suggests a critical role for the I-II cytoplasmic linker of the alpha(1)-subunit in channel modulation by the beta-subunit.
C1 UNIV IOWA,COLL MED,PROGRAM NEUROSCI,IOWA CITY,IA 52242.
   KYOTO UNIV,DEPT MED CHEM,KYOTO 606,JAPAN.
   YALE UNIV,HOWARD HUGHES MED INST,DEPT CELLULAR & MOLEC PHYSIOL,NEW HAVEN,CT 06536.
   UNIV BRITISH COLUMBIA,BIOTECHNOL LAB,VANCOUVER V6T 1Z3,BC,CANADA.
   UNIV BRITISH COLUMBIA,DEPT ZOOL,VANCOUVER V6T 1Z3,BC,CANADA.
   UNIV BRITISH COLUMBIA,DEPT NEUROSCI,VANCOUVER V6T 1Z3,BC,CANADA.
C3 University of Iowa; Kyoto University; Yale University; Howard Hughes Medical Institute; University of British Columbia; University of British Columbia; University of British Columbia
RP PRAGNELL, M (corresponding author), UNIV IOWA,COLL MED,HOWARD HUGHES MED INST,DEPT PHYSIOL & BIOPHYS,400 EMRB,IOWA CITY,IA 52242, USA.
NR 23
TC 550
Z9 640
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 67
EP 70
DI 10.1038/368067a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900055
PM 7509046
DA 2026-03-10
ER

PT J
AU HESSHAIMER, V
   HEIMANN, M
   LEVIN, I
AF HESSHAIMER, V
   HEIMANN, M
   LEVIN, I
TI RADIOCARBON EVIDENCE FOR A SMALLER OCEANIC CARBON-DIOXIDE SINK THAN PREVIOUSLY BELIEVED
SO NATURE
LA English
DT Article
ID tracer distributions; diffusion-model; co2
AB RADIOCARBON produced naturally in the upper atmosphere or artificially during nuclear weapons testing is the main tracer used to validate models of oceanic carbon cycling, in particular the exchange of carbon dioxide with the atmosphere(1-3) and the mixing parameters within the ocean itself(4-7). Here we test the overall consistency of exchange fluxes between all relevant compartments in a simple model of the global carbon cycle, using measurements of the long-term tropospheric CO2 concentration(8) and radiocarbon composition(9-12), the bomb C-14 inventory in the stratosphere(13,14) and a compilation of bomb detonation dates and strengths(15). We find that to balance the budget, we must invoke an extra source to account for 25% of the generally accepted uptake of bomb C-14 by the oceans(3). The strength of this source decreases from 1970 onwards, with a characteristic timescale similar to that of the ocean uptake. Significant radiocarbon transport from the remote high stratosphere and significantly reduced uptake of bomb C-14 by the biosphere can both be ruled out by observational constraints. We therefore conclude that the global oceanic bomb C-14 inventory should be revised downwards. A smaller oceanic bomb C-14 inventory also implies a smaller oceanic radiocarbon penetration depth(16), which in turn implies that the oceans take up 25% less anthropogenic CO2 than had previously been believed.
C1 MAX PLANCK INST METEOROL,D-20146 HAMBURG,GERMANY.
C3 Max Planck Society
RP HESSHAIMER, V (corresponding author), UNIV HEIDELBERG,INST UMWELTPHYS,NEUENHEIMER FELD 366,D-69120 HEIDELBERG,GERMANY.
NR 31
TC 105
Z9 110
U1 1
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 201
EP 203
DI 10.1038/370201a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100046
DA 2026-03-10
ER

PT J
AU LEE, HC
   AARHUS, R
   GRAEFF, R
   GURNACK, ME
   WALSETH, TF
AF LEE, HC
   AARHUS, R
   GRAEFF, R
   GURNACK, ME
   WALSETH, TF
TI CYCLIC ADP RIBOSE ACTIVATION OF THE RYANODINE RECEPTOR IS MEDIATED BY CALMODULIN
SO NATURE
LA English
DT Article
ID sea-urchin egg; calcium release; ca2+ release; microsm; modulation; channel; binding
AB CYCLIC ADP-ribose (cADPR) is a newly identified nucleotide(1,2) which can release calcium from a variety of cells(3-6), suggesting it is a messenger for mobilizing internal Ca2+ stores. Its cyclic structure has now been confirmed by X-ray crystallography(7). Available results are consistent with it being a modulator of Ca2+-induced Ca2+ releases(8-10). Here we report that sea urchin egg microsomes purified by Percoll gradients lose sensitivity to cADPR, but the response can be restored by a soluble protein in the supernatant. Purification and characterization of the protein indicate that it is calmodulin. It appears to be sensitizing the Ca2+ release mechanism because caffeine and strontium, agonists of Ca2+-induced Ca2+ release, can also mimic calmodulin in conferring cADPR-sensitivity. Although evidence indicates that cADPR may be an activator of the ryanodine receptor(8-10), present results point to the importance of accessory proteins such as calmodulin in modulating its activity.
C1 UNIV MINNESOTA,DEPT PHARMACOL,MINNEAPOLIS,MN 55455.
C3 University of Minnesota System; University of Minnesota Twin Cities
RP LEE, HC (corresponding author), UNIV MINNESOTA,DEPT PHYSIOL,MINNEAPOLIS,MN 55455, USA.
NR 19
TC 210
Z9 221
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 307
EP 309
DI 10.1038/370307a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900068
PM 8035880
DA 2026-03-10
ER

PT J
AU IIRI, T
   HERZMARK, P
   NAKAMOTO, JM
   VANDOP, C
   BOURNE, HR
AF IIRI, T
   HERZMARK, P
   NAKAMOTO, JM
   VANDOP, C
   BOURNE, HR
TI RAPID GDP RELEASE FROM G(S-ALPHA) IN PATIENTS WITH GAIN AND LOSS OF ENDOCRINE FUNCTION
SO NATURE
LA English
DT Article
ID crystal-structure; alpha-subunit; gtp-binding; g-protein; signal transduction; precocious puberty; pertussis toxin; ras proteins; resolution; hydrolysis
AB LUTEINIZING hormone stimulates testicular Leydig cells to produce testosterone by binding to a receptor that activates the G protein G(s) and adenylyl cyclase. Testotoxicosis is a form of precocious puberty in which the Leydig cells secrete testosterone in the absence of luteinizing hormone, often due to constitutive activation of the luteinizing hormone receptor and (indirectly) G(s) (refs 1-4). Here we study two unrelated boys suffering from a paradoxical combination of testotoxicosis and pseudohypoparathyroidism type Ia (PHP-Ia)(5), a condition marked by resistance to hormones acting through cyclic AMP (parathyroid hormone and thyroid-stimulating hormone) as well as a 50% decrease in erythrocyte G(s) activity (the remaining 50% is due to the normal G(s) allele)(5,6). In both patients, a mutation in the gene encoding the G(s) alpha-subunit replaced alanine at position 366 with serine(5). We show that this alpha(s)-A366S mutation constitutively activates adenylyl cyclase in vitro, causing hormone-independent cAMP accumulation when expressed in cultured cells, and accounting for the testotoxicosis phenotype (as cAMP stimulates testosterone secretion). Although alpha(s)-A366S is quite stable at testis temperature, it is rapidly degraded at 37 degrees C, explaining the PHP-Ia phenotype caused by loss of G(s) activity. In vitro experiments indicate that accelerated release of GDP causes both the constitutive activity and the thermolability of alpha(s)-A366S.
C1 UNIV CALIF SAN FRANCISCO, DEPT PHARMACOL, SAN FRANCISCO, CA 94143 USA.
   UNIV CALIF SAN FRANCISCO, DEPT MED, SAN FRANCISCO, CA 94143 USA.
   UNIV CALIF SAN FRANCISCO, CARDIOVASC RES INST, SAN FRANCISCO, CA 94143 USA.
   UNIV CALIF LOS ANGELES, DEPT PEDIAT, LOS ANGELES, CA 90024 USA.
   UNIV CALIF LOS ANGELES, DEPT BIOL CHEM, LOS ANGELES, CA 90024 USA.
C3 University of California System; University of California San Francisco; University of California System; University of California San Francisco; University of California System; University of California San Francisco; University of California System; University of California Los Angeles; University of California System; University of California Los Angeles
NR 28
TC 211
Z9 225
U1 0
U2 4
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 164
EP 168
DI 10.1038/371164a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100066
PM 8072545
DA 2026-03-10
ER

PT J
AU HOGREFE, A
   RUBIE, DC
   SHARP, TG
   SEIFERT, F
AF HOGREFE, A
   RUBIE, DC
   SHARP, TG
   SEIFERT, F
TI METASTABILITY OF ENSTATITE IN DEEP SUBDUCTING LITHOSPHERE
SO NATURE
LA English
DT Article
ID olivine-spinel transformation; system mg2sio4-fe2sio4; phase-transformations; focus earthquakes; thermal structure; high-pressures; mantle; transition; evolution; mechanism
AB OLIVINE and (Mg,Fe)SiO3 pyroxene, the most abundant minerals in the Earth's upper mantle, are believed to transform to high-pressure phases at similar to 400 km depth(1-5). The possible metastable persistence of olivine to greater depths in some subduction zones-with consequences for the origin of deep-focus earthquakes and the dynamics of subduction-has been discussed extensively(6-14) but the role of other mantle minerals has not been considered. We report here an experimental study of the kinetic behaviour of the magnesian pyroxene enstatite (MgSiO3) at upper-mantle conditions. We find that, whereas forsterite (Mg-olivine, Mg2SiO4) transforms rapidly to beta-phase at 1,200 degrees C and 16 GPa, the transformation of enstatite to beta-phase plus stishovite on the same time-scale requires much higher temperatures. At lower temperatures, enstatite transforms directly to the ilmenite structure, but only at pressures greater than 20 GPa. Enstatite should therefore persist metastably to greater depths than olivine in Subduction zones, transforming directly tb the ilmenite structure. The enstatite-ilmenite transformation is accompanied by a large decrease in volume, which should increase the stresses in subducting slabs, change the buoyancy forces that drive Subduction, and might also contribute to the origin of deep-focus earthquakes.
RP HOGREFE, A (corresponding author), UNIV BAYREUTH,BAYER GEOINST,POSTFACH 101251,D-95440 BAYREUTH,GERMANY.
NR 36
TC 79
Z9 90
U1 1
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 351
EP 353
DI 10.1038/372351a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700051
DA 2026-03-10
ER

PT J
AU JIN, Y
   MCNUTT, MK
   ZHU, YS
AF JIN, Y
   MCNUTT, MK
   ZHU, YS
TI EVIDENCE FROM GRAVITY AND TOPOGRAPHY DATA FOR FOLDING OF TIBET
SO NATURE
LA English
DT Article
ID continental collision; lithosphere; deformation; plate; tectonics; anomaly; thickness; model
AB Bouguer gravity and topography data from Tibet suggest that the surface of the plateau and the subsurface density interfaces are warped into two series of ridges and troughs trending parallel to the collision zone with wavelengths of 150 and 500 km. These folds are superimposed on an overall state of isostatic compensation owing to crustal thickening. Such folding is predicted from models of compressional shortening of a theologically layered plate. The results thus suggest the presence of a weak decoupling zone between the Tibetan crust and upper mantle.
C1 OCEAN UNIV QINGDAO,DEPT GEOL,QINGDAO 266003,PEOPLES R CHINA.
C3 Ocean University of China
RP JIN, Y (corresponding author), MIT,DEPT EARTH ATMOSPHER & PLANETARY SCI,CAMBRIDGE,MA 02139, USA.
NR 28
TC 126
Z9 141
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 669
EP 674
DI 10.1038/371669a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300046
DA 2026-03-10
ER

PT J
AU STERN, SA
   FESTOU, MC
   WEINTRAUB, DA
AF STERN, SA
   FESTOU, MC
   WEINTRAUB, DA
TI A MAP OF A COLLISIONALLY EVOLVING DUST DISK AROUND FOMALHAUT
SO NATURE
LA English
DT Article
ID millimeter observations; submillimeter; vega; shell; cloud; stars
AB THE presence of dust around normal (main-sequence) Stars is a possible signature of the early stages of planet formation. Scattered light from the star beta Pictoris provides evidence of a dust disk extending out to about 1,000 astronomical units(1), and the observation of far-infrared excess emission from several other main-sequence stars(2) suggests the presence of orbiting cold dust grains(3). Because the dynamical lifetime of this dust is short, it is thought to be supplied and replenished by collisions among a population of comets or asteroids(4-8). Observations by Chini et al.(9,10) of beta Pic and several other infrared-excess stars at a wavelength of 1.3 mm have supported the idea that they are surrounded by extended dust disks. Techniques developed recently now permit imaging at these wavelengths, and we have used these techniques to obtain a map of the dust disk around the nearby, prototypical infrared-excess star Fomalhaut with a spatial resolution of 80 AU. This image provides direct confirmation that the dust is distributed it. a disk-like structure, and shows that the structure extends about 200 AU from the star, farther than estimated previously(9,10). We estimate that a high rate of cometary and/or asteroidal collisions is required to maintain this disk.
C1 OBSERV MIDI PYRENEES,F-31400 TOULOUSE,FRANCE.
   VANDERBILT UNIV,DEPT PHYS & ASTRON,NASHVILLE,TN 37235.
C3 Universite de Toulouse; Universite Toulouse III - Paul Sabatier; Vanderbilt University
RP STERN, SA (corresponding author), SW RES INST,DEPT SPACE SCI,6220 CULEBRA RD,SAN ANTONIO,TX 78238, USA.
NR 24
TC 11
Z9 11
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 312
EP 314
DI 10.1038/368312a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500038
DA 2026-03-10
ER

PT J
AU RAO, VR
   COHEN, GB
   OPRIAN, DD
AF RAO, VR
   COHEN, GB
   OPRIAN, DD
TI RHODOPSIN MUTATION G90D AND A MOLECULAR MECHANISM FOR CONGENITAL NIGHT BLINDNESS
SO NATURE
LA English
DT Article
ID dominant retinitis-pigmentosa; bovine rhodopsin; gene
AB MUTATIONS in the gene for the visual pigment rhodopsin cause retinitis pigmentosa (RP) and congenital night blindness(1-7). Inheritance of the diseases is generally autosomal dominant and about 40 different rhodopsin mutations have been documented. Although the cell death and retinal degeneration associated with RP have been suggested to result from improper folding and accumulation of the mutant proteins in rod photoreceptor cells(8), this may not account for the disease in all cases. For example, RP mutations at Lys 296, site of Schiff base linkage to the retinal chromophore, result in constitutive;activation of the protein in vitro(9-11); that is, the mutants can catalytically activate the G protein transducin in the absence of chromophore and in the absence of light. Similarly, mutation of Ala 292 --> Glu activates opsin in vitro and causes night blindness(7). We show here that the mutation Gly 90 --> Asp (G90D) in the second transmembrane segment of rhodopsin, which causes congenital night blindness(12), also constitutively activates opsin. Furthermore, we show that Asp 90 can substitute for the Schiff base counterion, Glu 113, which is located in the third transmembrane segment of the protein. This demonstrates the proximity of Asp 90 and Lys 296 in the three-dimensional structure of rhodopsin and suggests that the constitutively activating mutations operate by a common molecular mechanism, disrupting a salt bridge between Lys 296 and the Schiff base counterion, Glu 113.
RP RAO, VR (corresponding author), BRANDEIS UNIV,GRAD DEPT BIOCHEM,WALTHAM,MA 02254, USA.
FU NEI NIH HHS [R01 EY007965] Funding Source: Medline
NR 31
TC 329
Z9 359
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 639
EP 642
DI 10.1038/367639a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800052
PM 8107847
DA 2026-03-10
ER

PT J
AU SU, XD
   TADDEI, N
   STEFANI, M
   RAMPONI, G
   NORDLUND, P
AF SU, XD
   TADDEI, N
   STEFANI, M
   RAMPONI, G
   NORDLUND, P
TI THE CRYSTAL-STRUCTURE OF A LOW-MOLECULAR-WEIGHT PHOSPHOTYROSINE PROTEIN PHOSPHATASE
SO NATURE
LA English
DT Article
ID cytosolic acid-phosphatase; bovine heart; catalytic mechanism; growth; refinement
AB PROTEIN tyrosine phosphorylation and dephosphorylation are central reactions for control of cellular division, differentiation and development(1). Here we describe the crystal structure of a low-molecular-weight phosphotyrosine protein phosphatase (PTPase)(2), a cytosolic phosphatase present in many mammalian cells. The enzyme catalyses the dephosphorylation of phosphotyrosine-containing substrates(3-6), and overexpression of the protein in normal and transformed cells inhibits cell. proliferation(7,8). The structure of the low-molecular-weight PTPase reveals an alpha/beta protein containing a phosphate-binding loop motif at the amino end of helix alpha 1. This motif includes the essential active-site residues Cys 12 and Arg 18 and bears striking similarities to the active-site motif recently described in the structure of human PTP1B(9). The structure ofthe low-molecular-weight PTPase supports a reaction mechanism involving the conserved Cys 12 as an attacking nucleophile in an in-line associative mechanism. The structure also suggests a catalytic role for Asp 129 in the reaction cycle.
C1 UNIV FLORENCE,DEPT BIOCHEM SCI,FLORENCE,ITALY.
C3 University of Florence
RP SU, XD (corresponding author), UNIV STOCKHOLM,DEPT MOLEC BIOL,STOCKHOLM,SWEDEN.
NR 23
TC 204
Z9 217
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 575
EP 578
DI 10.1038/370575a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700060
PM 8052313
DA 2026-03-10
ER

PT J
AU DOWNES, CS
   CLARKE, DJ
   MULLINGER, M
   GIMENEZABIAN, JF
   CREIGHTON, AM
   JOHNSON, RT
AF DOWNES, CS
   CLARKE, DJ
   MULLINGER, M
   GIMENEZABIAN, JF
   CREIGHTON, AM
   JOHNSON, RT
TI A TOPOISOMERASE II-DEPENDENT G2 CYCLE CHECKPOINT IN MAMMALIAN-CELLS
SO NATURE
LA English
DT Article
ID premature chromosome condensation; ultraviolet-irradiation; mitotic chromosm; strand breaks; egg extracts; dna; replication; separation; inhibition; caffeine
AB THE enzyme DNA topoisomerase II, which removes the catenations formed between the DNA molecules of sister chromatids during replication(1) and is a structural component of chromosome cores(2), is needed for chromosome condensation in yeast(3) and in Xenopus extracts(4-6). Inhibitors of topoisomerase II arrest mammalian cells before mitosis in the G2 phase of the cell cycle(7), but also produce DNA damage, which causes arrest through established checkpoint controls(8). It is open to question whether cells need topoisomerase II to leave G2, or control late-cycle progression in response to its activity. Bisdioxopiperazines are topoisomerase II inhibitors that act without producing direct DNA damage(9); the most potent, ICRF-193, blocks mammalian entry into but not exit from mitosis. Here we show that checkpoint-evading agents such as caffeine override this block to produce abortively condensed chromosomes, indicating that topoisomerase II is needed for complete condensation. We find that exit from G2 is regulated by a catenation-sensitive checkpoint mechanism which is distinct from the G2-damage checkpoint.
C1 UNIV LONDON ST BARTHOLOMEWS HOSP & MED COLL,DEPT REPROD PHYSIOL,MED CHEM LAB,LONDON EC1A 7BE,ENGLAND.
C3 University of London; Queen Mary University London
RP DOWNES, CS (corresponding author), UNIV CAMBRIDGE,DEPT ZOOL,CRC,MAMMALIAN CELL DNA REPAIR RES GRP,DOWNING ST,CAMBRIDGE CB2 3EJ,ENGLAND.
NR 30
TC 290
Z9 317
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 467
EP 470
DI 10.1038/372467a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200058
PM 7984241
DA 2026-03-10
ER

PT J
AU ROBERTS, CWM
   SHUTTER, JR
   KORSMEYER, SJ
AF ROBERTS, CWM
   SHUTTER, JR
   KORSMEYER, SJ
TI HOX11 CONTROLS THE GENESIS OF THE SPLEEN
SO NATURE
LA English
DT Article
ID t-cell leukemia; homeobox gene; developmental defects; targeted disruption; expression; murine; organization; hox-1.6; codes
AB MANY homeobox genes are clustered in a linear array along a chromosome, reflecting their ordered expression along the anterior-posterior axis of the embryo(1). Expression patterns(2,3) as well as grafting(4), ectopic expression(5,6) and loss-of-function experiments(7-11) suggest that the Hox genes encode a combinatorial system of positional specification along that axis. In contrast, the function of orphan homeobox genes(12) located at sites outside the four mammalian Hox clusters is less well understood. To assess the functional role of the orphan homeobox gene Hox11, we have generated Hox11-deficient mice through gene targeting. Hox11(-/-) mice have no spleen, but otherwise appear normal. Hox11 is normally expressed in the splenic anlage arising from the splanchnic mesoderm. Hox11(-/-) embryos have no cellular organization at the site of splenic development but all other splanchnic derivatives develop normally. Hox11 controls the genesis of a single organ, providing new insight into the genetic regulation of morphogenesis.
C1 WASHINGTON UNIV,SCH MED,DEPT MED,ST LOUIS,MO 63110.
   WASHINGTON UNIV,SCH MED,DEPT PATHOL,ST LOUIS,MO 63110.
C3 Washington University (WUSTL); Washington University (WUSTL)
RP ROBERTS, CWM (corresponding author), WASHINGTON UNIV,SCH MED,HOWARD HUGHES MED INST,ST LOUIS,MO 63110, USA.
NR 30
TC 249
Z9 273
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 747
EP 749
DI 10.1038/368747a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300060
PM 7908720
DA 2026-03-10
ER

PT J
AU STOREY, P
   TAN, S
   COLLETT, M
   WALLS, D
AF STOREY, P
   TAN, S
   COLLETT, M
   WALLS, D
TI PATH DETECTION AND THE UNCERTAINTY PRINCIPLE
SO NATURE
LA English
DT Article
AB QUANTUM mechanics predicts that any detector capable of determining the path taken by a particle through a double slit will destroy the interference. This follows from the principle of complementarity formulated by Niels Bohr: simultaneous observation of wave and particle behaviour is prohibited. But such a description makes no reference to the physical mechanism by which the interference is lost. In the best studied welcher Weg ('which path') detection schemes(1,2), interference is lost by the transfer of momentum to the particle whose path is being determined, the extent of momentum transfer satisfying the position-momentum uncertainty relation. This has prompted the question as to whether complementarity is always enforced in welcher Weg schemes by momentum transfer. Scully et al.(3) have recently responded in the negative, suggesting that complementarity must be accepted as an independent component of quantum mechanics, rather than as simply a consequence of the uncertainty principle. But we show here that, in any path detection scheme involving a fixed double slit, the amount of momentum transferred to the particle by a perfectly efficient detector (one capable of resolving the path unambiguously) is related to the slit separation in accordance with the uncertainty principle. If less momentum than this is transferred, interference is not completely destroyed and the path detector cannot be perfectly efficient.
RP STOREY, P (corresponding author), UNIV AUCKLAND, DEPT PHYS, PRIVATE BAG 92019, AUCKLAND, NEW ZEALAND.
NR 9
TC 112
Z9 117
U1 0
U2 11
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 626
EP 628
DI 10.1038/367626a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800047
DA 2026-03-10
ER

PT J
AU SPUDICH, JA
AF SPUDICH, JA
TI MOW MOLECULAR MOTORS WORK
SO NATURE
LA English
DT Article
ID myosin heavy-chain; actin filament; muscular-contraction; muscle-contraction; sliding distance; atomic model; step size; invitro; movement; actomyosin
AB What is the molecular basis of cell movement and changes in cell shape? The integration of three approaches is revealing how the molecular motors that drive these processes move and produce force.
C1 STANFORD UNIV,SCH MED,DEPT DEV BIOL,STANFORD,CA 94305.
C3 Stanford University
RP SPUDICH, JA (corresponding author), STANFORD UNIV,SCH MED,DEPT BIOCHEM,STANFORD,CA 94305, USA.
NR 59
TC 422
Z9 457
U1 0
U2 37
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 515
EP 518
DI 10.1038/372515a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200042
PM 7990922
DA 2026-03-10
ER

PT J
AU ASHFORD, MLJ
   BOND, CT
   BLAIR, TA
   ADELMAN, JP
AF ASHFORD, MLJ
   BOND, CT
   BLAIR, TA
   ADELMAN, JP
TI RETRACTED: CLONING AND FUNCTIONAL EXPRESSION OF A RAT-HEART K-ATP CHANNEL (RETRACTED ARTICLE. SEE VOL 378, PG 792, 1995)
SO NATURE
LA English
DT Article; Retracted Publication
ID potassium channels; ventricular myocytes; membrane patches; guinea-pig; cell; pinacidil
AB POTASSIUM channels that are ATP-sensitive (K-ATP) couple membrane potential to the metabolic status of the cell. K-ATP channels are inhibited by intracellular ATP and are stimulated by intracellular nucleotide diphosphates(1). K-ATP channel are important regulators of secretory processes and muscle contraction, and are targets for therapeutic treatment of type II diabetes by the inhibitory sulphonylureas(2) and for hypertension by activators such as pinacidil(3). In cardiac tissue, K-ATP channels are central regulators of post-ischaemic cardioprotection(4,5). Electrophysiological and pharmacological characteristics vary among K-ATP channels recorded from diverse tissues suggesting extensive molecular heterogeneity(1) A complementary DNA encoding a K-ATP channel was isolated from rat heart using the polymerase chain reaction. We report here that the expressed channels possess all of the essential features of native cardiac K-ATP channels, including sensitivity to intracellular nucleotides. In addition the cloned channels are activated by the potassium channel opener, pinacidil, but are not inhibited by the sulphonylurea, glibenclamide.
C1 OREGON HLTH SCI UNIV, VOLLUM INST, PORTLAND, OR 97201 USA.
   UNIV CAMBRIDGE, DEPT PHARMACOL, CAMBRIDGE CB2 1QJ, ENGLAND.
C3 Oregon Health & Science University; University of Cambridge
NR 25
TC 191
Z9 198
U1 1
U2 8
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 456
EP 459
DI 10.1038/370456a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700055
PM 8047164
DA 2026-03-10
ER

PT J
AU ADOLPHS, R
   TRANEL, D
   DAMASIO, H
   DAMASIO, A
AF ADOLPHS, R
   TRANEL, D
   DAMASIO, H
   DAMASIO, A
TI IMPAIRED RECOGNITION OF EMOTION IN FACIAL EXPRESSIONS FOLLOWING BILATERAL DAMAGE TO THE HUMAN AMYGDALA
SO NATURE
LA English
DT Article
ID circumplex model; identity; lesions; monkey
AB STUDIES in animals have shown that the amygdala receives highly processed visual input(1,2), contains neurons that respond selectively to faces(3), and that it participates in emotion(4,5) and social behaviour(6). Although studies in epileptic patients support its role in emotion(7), determination of the amygdala's function in humans has been hampered by the rarity of patients with selective amygdala lesions(8). Here, with the help of one such rare patient, we report findings that suggest the human amygdala may be indispensable to: (1) recognize fear in facial expressions; (2) recognize multiple emotions in a single facial expression; but (3) is not required to recognize personal identity from faces. These results suggest that damage restricted to the amygdala causes very specific recognition impairments, and thus constrains the broad notion that the amygdala is involved in emotion.
C1 SALK INST BIOL STUDIES,LA JOLLA,CA 92186.
C3 Salk Institute
RP ADOLPHS, R (corresponding author), UNIV IOWA,COLL MED,DEPT NEUROL,DIV COGNIT NEUROSCI,IOWA CITY,IA 52242, USA.
NR 29
TC 1656
Z9 1968
U1 4
U2 242
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 669
EP 672
DI 10.1038/372669a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700084
PM 7990957
DA 2026-03-10
ER

PT J
AU BURTON, KW
   COHEN, AS
   ONIONS, RK
   OHARA, MJ
AF BURTON, KW
   COHEN, AS
   ONIONS, RK
   OHARA, MJ
TI ARCHEAN CRUSTAL DEVELOPMENT IN THE LEWISIAN COMPLEX OF NORTHWEST SCOTLAND
SO NATURE
LA English
DT Article
ID isotopic evolution; scourie dykes; geochemistry; granulites; gneisses; earth; amphibolite; chronology; mantle; magmas
AB THE Lewisian complex of northwest Scotland is typical of many Archaean terrains and has a well documented history starting similar to 2,700 Myr ago(1-6). Here we present new isotopic data that extend this history back to 3,300 Myr, and provide some insight into how the earliest continental crust may have formed. The Lewisian is dominated by tonalite, trondhjemite and granodiorite (TTG) rocks, which require a mafic lithospheric source, rather than being direct mantle melts(7-11). But the mafic and ultramafic rocks in the high-grade granulite-facies part of this terrain show little evidence of a significantly older crustal history(12,13) and precursor material to the TTG lithologies has not yet been identified. Here we show that older amphibolite material has survived at a lower metamorphic grade. Coexisting amphibolite minerals yield indistinguishable Pb-207-Pb-206 and Sm-147-Nd-143 ages of 3,310+/-27 Myr and 3,298+/-73 Myr, respectively. These data are consistent with an origin for much of the Lewisian terrain by the re-melting of preexisting lithosphere, with an isotopic signature similar to that of the amphibolites studied here.
C1 UNIV WALES COLL CARDIFF, DEPT GEOL, CARDIFF CF1 3YG, S GLAM, WALES.
C3 Cardiff University
RP BURTON, KW (corresponding author), UNIV CAMBRIDGE, DEPT EARTH SCI, DOWNING ST, CAMBRIDGE CB2 3EQ, ENGLAND.
NR 32
TC 18
Z9 18
U1 0
U2 6
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 552
EP 555
DI 10.1038/370552a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700053
DA 2026-03-10
ER

PT J
AU COWIE, GL
   HEDGES, JI
AF COWIE, GL
   HEDGES, JI
TI BIOCHEMICAL INDICATORS OF DIAGENETIC ALTERATION IN NATURAL ORGANIC-MATTER MIXTURES
SO NATURE
LA English
DT Article
ID coastal marine-environment; amino-acids; sea sediments; deep ocean; lignin; nitrogen; sugars; decomposition; reactivity; degradation
AB THE extent of degradation of natural organic mixtures largely determines their utility as records of depositional history, and their potential to act as nutritional substrates and fossil fuel sources. The degree of decomposition is usually inferred from the physical setting of the deposits(1) or from bulk chemical composition(2), but in both these cases the interpretation can bk obscured by several factors(3). We report here a study of aldoses and amino acids in samples collected from a variety of marine depositional environments and representing widely different stages of alteration. We identify consistent trends in three compositional characteristics: the percentage of organic carbon in the form of aldoses and protein amino acids, the percentage of total nitrogen present as protein amino acids, and the percentage of total amino acids present as beta-alanine and gamma-aminobutyric acid. Each of these parameters is sensitive to a different stage of alteration, and they appear to be uncompromised by source variations. Applied together, they offer concordant information on the relative diagenetic stage and reaction potential of natural organic mixtures under both aerobic and anaerobic depositional conditions.
C1 UNIV WASHINGTON,SCH OCEANOG,SEATTLE,WA 98195.
C3 University of Washington; University of Washington Seattle
RP COWIE, GL (corresponding author), UNIV BRITISH COLUMBIA,DEPT OCEANOG,VANCOUVER V6T 1Z4,BC,CANADA.
NR 35
TC 351
Z9 413
U1 1
U2 98
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 304
EP 307
DI 10.1038/369304a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900044
DA 2026-03-10
ER

PT J
AU KURIHARA, Y
   KURIHARA, H
   SUZUKI, H
   KODAMA, T
   MAEMURA, K
   NAGAI, R
   ODA, H
   KUWAKI, T
   CAO, WH
   KAMADA, N
   JISHAGE, K
   OUCHI, Y
   AZUMA, S
   TOYODA, Y
   ISHIKAWA, T
   KUMADA, M
   YAZAKI, Y
AF KURIHARA, Y
   KURIHARA, H
   SUZUKI, H
   KODAMA, T
   MAEMURA, K
   NAGAI, R
   ODA, H
   KUWAKI, T
   CAO, WH
   KAMADA, N
   JISHAGE, K
   OUCHI, Y
   AZUMA, S
   TOYODA, Y
   ISHIKAWA, T
   KUMADA, M
   YAZAKI, Y
TI ELEVATED BLOOD-PRESSURE AND CRANIOFACIAL ABNORMALITIES IN MICE DEFICIENT IN ENDOTHELIN-1
SO NATURE
LA English
DT Article
ID developmental defects; targeted disruption; ventral surface; binding-sites; rat medulla; gene; expression; peptide; cells; hypertension
AB The endothelin-l (ET-1) gene was disrupted in mouse embryonic stem cells by homologous recombination to generate mice deficient in ET-1. These: ET-1(-/-) homozygous mice die of respiratory failure at birth and have morphological abnormalities of the pharyngeal-arch-derived craniofacial tissues and organs. ET-1(+/-) heterozygous mice, which produce lower levels of ET-1 than wild-type mice, develop elevated blood pressure. These results suggest that ET-1 is essential for normal mouse development and may also play a physiological role in cardiovascular homeostasis.
C1 UNIV TOKYO, FAC MED, DEPT INTERNAL MED 3, BUNKYO KU, TOKYO 113, JAPAN.
   UNIV TOKYO, FAC MED, DEPT PATHOL, BUNKYO KU, TOKYO 113, JAPAN.
   UNIV TOKYO, FAC MED, DEPT PHYSIOL, BUNKYO KU, TOKYO 113, JAPAN.
   UNIV TOKYO, FAC MED, DEPT GERIATR, BUNKYO KU, TOKYO 113, JAPAN.
   CHUGAI PHARMACEUT CO LTD, GOTEMBA, SHIZUOKA 412, JAPAN.
   UNIV TOKYO, INST MED SCI, DEPT REPROD & DEV BIOL, MINATO KU, TOKYO 108, JAPAN.
C3 University of Tokyo; University of Tokyo; University of Tokyo; University of Tokyo; Roche Holding; Roche Holding Japan; Chugai Pharmaceutical Co., Ltd.; University of Tokyo
NR 47
TC 876
Z9 948
U1 0
U2 15
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 703
EP 710
DI 10.1038/368703a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300048
PM 8152482
DA 2026-03-10
ER

PT J
AU JAMESON, SC
   HOGQUIST, KA
   BEVAN, MJ
AF JAMESON, SC
   HOGQUIST, KA
   BEVAN, MJ
TI SPECIFICITY AND FLEXIBILITY IN THYMIC SELECTION
SO NATURE
LA English
DT Article
ID t-cell-receptor; transgenic mice; positive selection; peptide binding; beta-2-microglobulin; thymocytes; expression; deficient; tolerance; antigen
AB DURING positive selection, developing thymocytes are rescued from programmed cell death by T-cell receptor (TCR)-mediated recognition of major histocompatibility complex (MHC) molecules(1-3). MHC-bound peptides contribute to this process(4-8). Recently we identified individual MHC-binding peptides which can induce positive selection of a single TCR(9). Here we examine peptide fine specificity in positive selection. These data suggest that a direct TCR-peptide interaction occurs during this event, and strengthens the correlation between selecting peptides and TCR antagonists(9,10). Certain positively selecting peptides are weakly antigenic(9). We demonstrate that thymocytes 'educated' on such a peptide are specifically non-responsive to it and have decreased CD8 expression levels. Similar reduction of CD8 expression on mature T cells converts a TCR agonist into a TCR antagonist. These data indicate that thymocytes may maintain self-tolerance towards a positively selecting ligand by regulating co-receptor expression.
RP JAMESON, SC (corresponding author), UNIV WASHINGTON,HOWARD HUGHES MED INST,DEPT IMMUNOL,SEATTLE,WA 98195, USA.
FU Howard Hughes Medical Institute Funding Source: Medline; NIAID NIH HHS [R01 AI019335] Funding Source: Medline
NR 25
TC 211
Z9 228
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 750
EP 752
DI 10.1038/369750a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100062
PM 8008067
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI UNAM - CRADLE OF MEXICAN SCIENCE
SO NATURE
LA English
DT Article
NR 1
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 794
EP 795
DI 
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700027
DA 2026-03-10
ER

PT J
AU SILVI, B
   SAVIN, A
AF SILVI, B
   SAVIN, A
TI CLASSIFICATION OF CHEMICAL-BONDS BASED ON TOPOLOGICAL ANALYSIS OF ELECTRON LOCALIZATION FUNCTIONS
SO NATURE
LA English
DT Article
ID density
AB THE definitions currently used to classify chemical bonds (in terms of bond order, covalency versus ionicity and so forth) are derived from approximate theories(1-3) and are often imprecise. Here we outline a first step towards a more rigorous means of classification based on topological analysis of local quantum-mechanical functions related to the Pauli exclusion principle. The local maxima of these functions define 'localization attractors', of which there are only three basic types: bonding, non-bonding and core. Bonding attractors lie between the core attractors (which themselves surround the atomic nuclei) and characterize the shared-electron interactions. The number of bond attractors is related to the bond multiplicity. The spatial organization of localization attractors provides a basis for a well-defined classification of, bonds, allowing an absolute characterization of covalency versus ionicity to be obtained from observable properties such as electron densities.
RP SILVI, B (corresponding author), UNIV PARIS 06,DYNAM INTERACT MOLEC LAB,UPR271,4 PL JUSSIEU,F-75005 PARIS,FRANCE.
NR 26
TC 3888
Z9 4028
U1 9
U2 363
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 683
EP 686
DI 10.1038/371683a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300049
DA 2026-03-10
ER

PT J
AU SMEYNE, RJ
   KLEIN, R
   SCHNAPP, A
   LONG, LK
   BRYANT, S
   LEWIN, A
   LIRA, SA
   BARBACID, M
AF SMEYNE, RJ
   KLEIN, R
   SCHNAPP, A
   LONG, LK
   BRYANT, S
   LEWIN, A
   LIRA, SA
   BARBACID, M
TI SEVERE SENSORY AND SYMPATHETIC NEUROPATHIES IN MICE CARRYING A DISRUPTED TRK/NGF RECEPTOR GENE
SO NATURE
LA English
DT Article
ID nerve growth-factor; root ganglion neurons; proto-oncogene; expression; ngf
AB NERVE growth factor (NGF) induces neurite outgrowth and promotes survival of embryonic sensory and sympathetic neurons in culture(1,2). In vivo, NGF decreases the extent of naturally occurring cell death in developing sympathetic ganglia and protects cholinergic neurons of the basal forebrain and caudatoputamen(1-3). NGF interacts with the low-affinity p75 receptor and with Trk, a receptor tyrosine kinase encoded by the trk proto-oncogene(4,5). To study the role of Trk in vivo, we have ablated the gene in embryonic stem cells by homologous recombination. Mice lacking Trk have severe sensory and sympathetic neuropathies and most die within one month of birth. They have extensive neuronal cell loss in trigeminal, sympathetic and dorsal root ganglia, as well as a decrease in the cholinergic basal forebrain projections to the hippocampus and cortex. These findings demonstrate that Trk is the primary mediator of the trophic actions of NGF in vivo and that this signalling pathway plays a crucial role in the development of both the peripheral and the central nervous systems.
C1 EUROPEAN MOLEC BIOL LAB,DIFFERENTIAT PROGRAMME,D-69012 HEIDELBERG,GERMANY.
C3 European Molecular Biology Laboratory (EMBL)
RP SMEYNE, RJ (corresponding author), BRISTOL MYERS SQUIBB PHARMACEUT RES INST,DEPT MOLEC BIOL,PRINCETON,NJ 08543, USA.
NR 20
TC 847
Z9 978
U1 0
U2 27
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 246
EP 249
DI 10.1038/368246a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000056
PM 8145823
DA 2026-03-10
ER

PT J
AU SONGAILA, A
   COWIE, LL
   VOGT, S
   KEANE, M
   WOLFE, AM
   HU, EM
   OREN, AL
   TYTLER, DR
   LANZETTA, KM
AF SONGAILA, A
   COWIE, LL
   VOGT, S
   KEANE, M
   WOLFE, AM
   HU, EM
   OREN, AL
   TYTLER, DR
   LANZETTA, KM
TI MEASUREMENT OF THE MICROWAVE BACKGROUND TEMPERATURE AT A REDSHIFT OF 1.776
SO NATURE
LA English
DT Article
ID absorption; spectrum; carbon
AB HOT Big Bang cosmology predicts that the temperature of the cosmic microwave background radiation will increase linearly with increasing redshift to early in the history of the Universe. The local background temperature (2.7 K) is known very accurately from direct measurements(1-3), but other techniques must be used to estimate it at non-zero redshifts. One way is to determine the excitation of atomic transitions in absorbing clouds along the lines-of-sight to distant quasars(4). When the transitions are in equilibrium with the microwave background radiation, the radiation will populate the fine-structure levels of the ground states of certain atoms, and the relative populations of the levels can be used to calculate its temperature. Here we report the detection of absorption from the first fine-structure level of neutral carbon atoms in a cloud at a redshift of 1.776, towards the quasar Q1331 + 170. The population ratio yields a temperature of 7.4 +/- 0.8 K, assuming that no other significant sources of excitation are present. This agrees with the theoretical prediction of 7.58 K.
C1 UNIV CALIF SANTA CRUZ,LICK OBSERV,SANTA CRUZ,CA 95064.
   UNIV CALIF SAN DIEGO,DEPT ASTROPHYS & SPACE SCI,LA JOLLA,CA 92093.
   SUNY STONY BROOK,DEPT EARTH & SPACE SCI,ASTRON PROGRAM,STONY BROOK,NY 11794.
C3 University of California System; University of California Santa Cruz; University of California System; University of California San Diego; State University of New York (SUNY) System; Stony Brook University
RP SONGAILA, A (corresponding author), UNIV HAWAII,INST ASTRON,2680 WOODLAWN DR,HONOLULU,HI 96822, USA.
NR 20
TC 86
Z9 89
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 43
EP 45
DI 10.1038/371043a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100043
DA 2026-03-10
ER

PT J
AU FRYDMAN, J
   NIMMESGERN, E
   OHTSUKA, K
   HARTL, FU
AF FRYDMAN, J
   NIMMESGERN, E
   OHTSUKA, K
   HARTL, FU
TI FOLDING OF NASCENT POLYPEPTIDE-CHAINS IN A HIGH-MOLECULAR-MASS ASSEMBLY WITH MOLECULAR CHAPERONES
SO NATURE
LA English
DT Article
ID t-complex polypeptide-1; escherichia-coli dnaj; heat-shock proteins; stress proteins; binding-specificity; peptide-binding; central cavity; groel; translocation; cell
AB The folding of polypeptides emerging from ribosomes was analysed in a mammalian translation system using firefly luciferase as a model protein. The growing polypeptide interacts with a specific set of molecular chaperones, including Hsp70, the DnaJ homologue Hsp40 and the chaperonin TRiC. The ordered assembly of these components on the nascent chain forms a high molecular mass complex that allows the cotranslational formation of protein domains and the completion of folding once the chain is released from the ribosome.
C1 MEM SLOAN KETTERING CANC CTR,HOWARD HUGHES MED INST,NEW YORK,NY 10021.
   MEM SLOAN KETTERING CANC CTR,CELLULAR BIOCHEM & BIPHYS PROGRAM,NEW YORK,NY 10021.
   AICHI CANC CTR,EXPTL RADIOL LAB,CHIKUSA KU,NAGOYA,AICHI 464,JAPAN.
C3 Memorial Sloan Kettering Cancer Center; Howard Hughes Medical Institute; Memorial Sloan Kettering Cancer Center; Aichi Cancer Center
NR 50
TC 589
Z9 667
U1 0
U2 36
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 111
EP 117
DI 10.1038/370111a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400047
PM 8022479
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI HEALTH MATTERS IN TRANSITION
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 798
EP 798
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700032
PM 8159234
DA 2026-03-10
ER

PT J
AU MEERHOLZ, K
   VOLODIN, BL
   SANDALPHON
   KIPPELEN, B
   PEYGHAMBARIAN, N
AF MEERHOLZ, K
   VOLODIN, BL
   SANDALPHON
   KIPPELEN, B
   PEYGHAMBARIAN, N
TI A PHOTOREFRACTIVE POLYMER WITH HIGH OPTICAL GAIN AND DIFFRACTION EFFICIENCY NEAR 100-PERCENT
SO NATURE
LA English
DT Article
ID steady-state
AB PHOTOREFRACTIVE materials are of considerable interest for the development of all-optical devices(1). The photorefractive effect appears in materials that exhibit an electric-field-dependent refractive index and that are photosensitive, such that the spatial distribution of photogenerated charge carriers is modified on irradiation with light. The diffraction pattern formed by the interference of two coherent light beams within such a material generates a nonuniform internal electric field that in turn modulates the refractive index. The resulting refractive-index pattern forms a grating that can diffract Light and thereby give rise to two-beam coupling, whereby one of the writing beams gains energy at the expense of the other-a property that can be exploited in photonic devices. Although the best photorefractive materials currently available are inorganic crystals such as LiNbO3, there is considerable interest in the development of photorefractive polymers(2-8), owing to their structural flexibility, ease of processing and lower cost. We describe here a polymer composite with excellent photorefractive properties. We have achieved a diffraction efficiency approaching 100% and a net two-beam coupling gain of more than 200 cm(-1), making these polymeric materials suitable for immediate application in areas such as dynamic holographic storage and optical information processing(1).
C1 INST PHYS & CHIM MAT STRASBOURG,OPT NONLINEAIRE & OPTOELECTR GRP,UNITE MIXTE CNRS ULP EHICS,F-67084 STRASBOURG,FRANCE.
C3 Universites de Strasbourg Etablissements Associes; Universite de Strasbourg
RP MEERHOLZ, K (corresponding author), UNIV ARIZONA,CTR OPT SCI,TUCSON,AZ 85721, USA.
NR 15
TC 706
Z9 743
U1 0
U2 82
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 497
EP 500
DI 10.1038/371497a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900049
DA 2026-03-10
ER

PT J
AU DRAPKIN, R
   REARDON, JT
   ANSARI, A
   HUANG, JC
   ZAWEL, L
   AHN, KJ
   SANCAR, A
   REINBERG, D
AF DRAPKIN, R
   REARDON, JT
   ANSARI, A
   HUANG, JC
   ZAWEL, L
   AHN, KJ
   SANCAR, A
   REINBERG, D
TI DUAL ROLE OF TFIIH IN DNA EXCISION-REPAIR AND IN TRANSCRIPTION BY RNA-POLYMERASE-II
SO NATURE
LA English
DT Article
ID xeroderma-pigmentosum; subunit; cloning; motifs
AB THE RNA polymerase II general transcription factor TFIIH is composed of several polypeptides. The observation that the largest subunit of TFIIH is the excision-repair protein XPB/ERCC3 (ref. 1), a helicase implicated in the human DNA-repair disorders xeroderma pigmentosum (XP) and Cockayne's syndrome(2,3), suggests a functional link between transcription and DNA repair(4,5). To understand the connection between these two cellular processes, we have extensively purified and functionally analysed TFIIH. We find that TFIIH has a dual role, being required for basal transcription of class II genes and for participation in DNA-excision repair. TFIIH is shown to complement three different cell extracts deficient in excision repair: XPB/ERCC3, XPC and XPD/ERCC2. The complementation of XPB and XPD is a consequence of ERCC3 and ERCC2 being integral subunits of TFIIH, whereas complementation of XPC is due to an association of this polypeptide with TFIIH. We found that the general transcription factor IIE negatively modulates the helicase activity of TFIIH through a direct interaction between TFIIE and the ERCC3 subunit of TFIIH.
C1 UNIV MED & DENT NEW JERSEY,ROBERT WOOD JOHNSON MED SCH,DEPT BIOCHEM,PISCATAWAY,NJ 08854.
   UNIV N CAROLINA,SCH MED,DEPT BIOCHEM & BIOPHYS,CHAPEL HILL,NC 27599.
C3 Rutgers University System; Rutgers University New Brunswick; Rutgers University Biomedical & Health Sciences; University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina School of Medicine
NR 28
TC 430
Z9 466
U1 1
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 769
EP 772
DI 10.1038/368769a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300066
PM 8152490
DA 2026-03-10
ER

PT J
AU MIZUNO, A
   ONISHI, T
   HAYASHI, M
   OHASHI, N
   SUNADA, K
   HASEGAWA, T
   FUKUI, Y
AF MIZUNO, A
   ONISHI, T
   HAYASHI, M
   OHASHI, N
   SUNADA, K
   HASEGAWA, T
   FUKUI, Y
TI MOLECULAR CLOUD CONDENSATION AS A TRACER OF LOW-MASS STAR-FORMATION
SO NATURE
LA English
DT Article
ID dense cores; evolution; outflows
AB STARS form inside dense clouds of molecular gas, but the details of the process, such as the quantity of gas that goes into stars and the rate at which the gas collapses, are still unknown. The earliest stages of cloud collapse are particularly poorly understood; some theoretical models exist(1-4), but there has been no observational evidence to support them. Here we report molecular emission-line data from the Taurus molecular cloud, which allows us to follow the earliest stages of cloud collapse. We find, contrary to previous results(5), that the cloud cores without young stars are less dense and more extended than those with stars, and that the timescale of core collapse suggested by the data is a few hundred thousand years. This is in good agreement with a model in which the formation rate of low-mass stars is controlled by ambipolar diffusion-the relative drift of neutral molecules with respect to magnetic field lines in the cloud(1,3).
C1 UNIV TOKYO, DEPT ASTRON, BUNKYO KU, TOKYO 113, JAPAN.
   NATL ASTRON OBSERV, NOBEYAMA RADIO OBSERV, MINAMIMAKI, NAGANO 38413, JAPAN.
   UNIV TOKYO, INST ASTRON, MITAKA, TOKYO 181, JAPAN.
C3 University of Tokyo; National Institutes of Natural Sciences (NINS) - Japan; National Astronomical Observatory of Japan (NAOJ); University of Tokyo
RP MIZUNO, A (corresponding author), NAGOYA UNIV, DEPT ASTROPHYS, NAGOYA 46401, JAPAN.
NR 18
TC 70
Z9 71
U1 0
U2 0
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 719
EP 721
DI 10.1038/368719a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300050
DA 2026-03-10
ER

PT J
AU KLENERMAN, P
   ROWLANDJONES, S
   MCADAM, S
   EDWARDS, J
   DAENKE, S
   LALLOO, D
   KOPPE, B
   ROSENBERG, W
   BOYD, D
   EDWARDS, A
   GIANGRANDE, P
   PHILLIPS, RE
   MCMICHAEL, AJ
AF KLENERMAN, P
   ROWLANDJONES, S
   MCADAM, S
   EDWARDS, J
   DAENKE, S
   LALLOO, D
   KOPPE, B
   ROSENBERG, W
   BOYD, D
   EDWARDS, A
   GIANGRANDE, P
   PHILLIPS, RE
   MCMICHAEL, AJ
TI CYTOTOXIC T-CELL ACTIVITY ANTAGONIZED BY NATURALLY-OCCURRING HIV-1 GAG VARIANTS
SO NATURE
LA English
DT Article
ID lymphocytes-t; receptor; peptides; individuals; recognition; virus
AB MOST asymptomatic individuals infected with HIV-1 have a cytotoxic T lymphocyte (CTL) response to the virus Gag proteins which can be demonstrated in vitro(1,2). Epitopes have been mapped in p17 Gag and p24 Gag restricted by HLA-B8 (p17-3 and p24-13) and -B27 (p24-14)(2,3). Viruses isolated from patients who make CTL responses to these peptides vary within the genetic sequences encoding these epitopes and some mutations lead to reduction in killing activity in vitro(4). This mas attributed to either failure of the variant epitope to bind major histocompatibility complex class I or failure of T-cell receptors to bind the presented peptide. But peptide variants of class I-restricted epitopes cause 'antagonism', that is, the presence of a variant epitope (in the form of peptide) inhibits normal lysis of targets presenting the original epitope(5,6). This mirrors similar findings in class II-restricted systems(7-10). Here we report that naturally occurring variant forms of p17-3, p24-13 and p24-14 may cause antagonism of CTL lines derived from the same individuals. The effect is present if the epitopes are derived from synthetic peptides and when they are processed from full-length proteins expressed by either recombinant vaccinia constructs or replicating HIV.
C1 UNIV OXFORD,INST MOLEC MED,OXFORD OX3 9DU,ENGLAND.
   RADCLIFFE INFIRM,DEPT GENITOURINARY MED,OXFORD OX3 7LJ,ENGLAND.
   CHURCHILL HOSP,OXFORD HAEMOPHILIA CTR,OXFORD OX3 7LV,ENGLAND.
C3 University of Oxford; Radcliffe Infirmary
RP KLENERMAN, P (corresponding author), UNIV OXFORD,NUFFIELD DEPT CLIN MED,DIV MOLEC SCI,OXFORD OX3 9DU,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 18
TC 405
Z9 432
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 403
EP 407
DI 10.1038/369403a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400058
PM 7515165
DA 2026-03-10
ER

PT J
AU JOHNSTONE, RA
AF JOHNSTONE, RA
TI FEMALE PREFERENCE FOR SYMMETRICAL MALES AS A BY-PRODUCT OF SELECTION FOR MATE RECOGNITION
SO NATURE
LA English
DT Article
ID male sexual ornaments; fluctuating asymmetry; evolution; patterns; stress; bias
AB FLUCTUATING asymmetry (FA) refers to the random, stress-induced deviations from perfect symmetry that develop during the growth of bilaterally symmetrical traits(1,2). Individual differences in the level of FA may influence mate choice(3): in a number of species, females prefer to mate with males that have more symmetrical sexual ornaments(4-7). As the degree of FA has been shown to reflect the ability of individuals to cope with a wide variety of environmental stresses(2,8,9), it has been suggested that mating preferences for symmetry evolve for adaptive reasons, because the degree of FA provides honest information about male quality(10,11). Here I use simple, artificial neural networks to show that such preferences are likely to arise in the absence of any link between symmetry and quality, as a by-product of selection for mate recognition.
RP JOHNSTONE, RA (corresponding author), UNIV CAMBRIDGE,DEPT ZOOL,DOWNING ST,CAMBRIDGE CB2 3EJ,ENGLAND.
NR 21
TC 165
Z9 174
U1 0
U2 42
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 172
EP 175
DI 10.1038/372172a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800054
PM 7969449
DA 2026-03-10
ER

PT J
AU RAZEGHI, M
AF RAZEGHI, M
TI HIGH-POWER LASER-DIODES BASED ON INGAASP ALLOYS
SO NATURE
LA English
DT Article
ID quantum-well lasers
AB High-power, high-coherence solid-state lasers, based on dielectric materials such as ruby or Nd:YAG (yttrium aluminium garnet), have many civilian acid military applications. The active media in these lasers are insulating, and must therefore be excited (or 'pumped') by optical, rather than electrical, means. Conventional gas-discharge lamps can be used as the pumping source, but semiconductor diode lasers are more efficient, as their wavelength can be tailored to match the absorption properties of tbe lasing material. Semiconducting AlGaAs alloys are widely used for this purpose(1,2), but oxidation of the aluminium and the spreading of defects during device operation limit the lifetime of the diodes(3), and hence the reliability of the system as a whole, Aluminium-free InGaAsP compounds, on the other hand, do not have these lifetime-limiting properties(4-8). We report here the fabrication of high-power lasers based on InGaAsP (lattice-matched to GaAs substrates), which operate over the same wavelength range as conventional AlGaAs laser diodes and show significantly improved reliability. The other optical and electrical properties of these diodes are either comparable or superior to those of the AlGaAs system.
RP RAZEGHI, M (corresponding author), NORTHWESTERN UNIV,DEPT ELECT ENGN & COMP SCI,CTR QUANTUM DEVICES,EVANSTON,IL 60208, USA.
NR 14
TC 56
Z9 92
U1 1
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 631
EP 633
DI 10.1038/369631a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900049
DA 2026-03-10
ER

PT J
AU LAGAGE, PO
   PANTIN, E
AF LAGAGE, PO
   PANTIN, E
TI DUST DEPLETION IN THE INNER DISK OF BETA-PICTORIS AS A POSSIBLE INDICATOR OF PLANETS
SO NATURE
LA English
DT Article
ID circumstellar disk; silicates; system; stars; iras
AB IT is not yet possible to see planets orbiting other stars, although this may soon change as observing methods improve(1). Indirect evidence for the presence of circumstellar dust disks out of which planets could form has been obtained for several stars, in the form of excess infrared emission, presumed to be from the hot dust(2,3). Planets orbiting in such dust disks would be expected to sweep out dust-free tracks(4). Indirect evidence for dust-free regions has been reported(5-9), based on an analysis of the spectral energy distribution, but the interpretation of the observation is not unique(7,9). Here we present an infrared image of the inner dust disk of the star beta Pictoris with a linear resolution of 5 astronomical units (AU), equivalent to the distance from the Sun to Jupiter. We find that the dust is asymmetrically distributed and is clearly depleted within 40 AU Of the star, which we interpret as indicating the possible presence of at least one planetary body orbiting beta Pictoris.
RP LAGAGE, PO (corresponding author), CTR ETUD SACLAY,CEA,DSM,DAPNIA,SERV ASTROPHYS,F-91191 GIF SUR YVETTE,FRANCE.
NR 27
TC 134
Z9 142
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 628
EP 630
DI 10.1038/369628a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900048
DA 2026-03-10
ER

PT J
AU KAGI, D
   LEDERMANN, B
   BURKI, K
   SEILER, P
   ODERMATT, B
   OLSEN, KJ
   PODACK, ER
   ZINKERNAGEL, RM
   HENGARTNER, H
AF KAGI, D
   LEDERMANN, B
   BURKI, K
   SEILER, P
   ODERMATT, B
   OLSEN, KJ
   PODACK, ER
   ZINKERNAGEL, RM
   HENGARTNER, H
TI CYTOTOXICITY MEDIATED BY T-CELLS AND NATURAL-KILLER-CELLS IS GREATLY IMPAIRED IN PERFORIN DEFICIENT MICE
SO NATURE
LA English
DT Article
ID lymphocytic choriomeningitis virus; pore-forming protein; serine proteases; cyto-toxicity; target-cells; stem-cells; invivo; expression; infection; granules
AB Perforin-deficient mice have been generated by homologous recombination to determine whether the effects of CD8(+) cytolytic T cells and natural killer cells are mediated by pore formation involving perforin. These mice are viable and fertile and have normal numbers of CD8(+) T cells and natural killer cells which do not lyse virus-infected or allogeneic fibroblasts or natural killer target cells in vitro. The mice fail to clear lymphocytic choriomeningitis virus and they eliminate fibrosarcoma tumour cells with reduced efficiency. Perforin is therefore a key effector molecule for T-cell- and natural killer-cell-mediated cytolysis.
C1 SANDOZ PHARMA LTD, PRECLIN RES, CH-4002 BASEL, SWITZERLAND.
   UNIV MIAMI, DEPT MICROBIOL & IMMUNOL, MIAMI, FL 33101 USA.
C3 Novartis; Sandoz; University of Miami
RP KAGI, D (corresponding author), UNIV ZURICH, INST EXPTL IMMUNOL, DEPT PATHOL, CH-8091 ZURICH, SWITZERLAND.
NR 49
TC 1560
Z9 1749
U1 8
U2 80
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 31
EP 37
DI 10.1038/369031a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000043
PM 8164737
DA 2026-03-10
ER

PT J
AU RAHMSTORF, S
AF RAHMSTORF, S
TI RAPID CLIMATE TRANSITIONS IN A COUPLED OCEAN-ATMOSPHERE MODEL
SO NATURE
LA English
DT Article
ID north-atlantic; thermohaline circulation; deep circulation; sea
AB RECENT geochemical data(1,2) have challenged the view that rapid climate fluctuations in the North Atlantic at the end of the last glacial mere caused by the thermohaline circulation of the ocean being switched 'on' or 'off'. Instead, these data suggest that the circulation pattern must have switched between a warm, deep mode and a cold, shallow mode, probably associated with different sites of deep convection(3). Here I present simulations with a three-dimensional ocean model, coupled to an idealized atmosphere, which show this kind of transition. The mechanism for the transition is a rearrangement of convection in the North Atlantic, triggered by a brief freshwater pulse. This results in a drop in sea surface temperature in the North Atlantic by up to 5 degrees C within less than 10 years. The rate of North Atlantic Deep Water (NADW) formation is the same in the cold climate as in the warm climate, but NADW sinks to intermediate depths only, while Antarctic Bottom Water pushes north to fill the entire abyssal Atlantic.
RP RAHMSTORF, S (corresponding author), INST MEERESKUNDE,DUSTEMBROOKER WEG 20,D-24105 KIEL,GERMANY.
NR 22
TC 197
Z9 210
U1 0
U2 24
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 82
EP 85
DI 10.1038/372082a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800075
DA 2026-03-10
ER

PT J
AU FENG, S
   BEIN, T
AF FENG, S
   BEIN, T
TI GROWTH OF ORIENTED MOLECULAR-SIEVE CRYSTALS ON ORGANOPHOSPHONATE FILMS
SO NATURE
LA English
DT Article
ID zeolite; recognition; multilayers; membrane; surfaces
AB THE successful construction Of complex organic/inorganic biomimetic systems(1-3) has demonstrated the great power of supramolecular pre-organization and templating in controlling crystal growth(4). For instance, polar organic surfaces or surface-attached polar groups can induce the formation of thin films of iron oxide(5). It would be of great interest, for the design of novel devices such as sensors or catalyst membranes(6), to be able to control the growth on surfaces of porous crystals with oriented channels: such channels could, for example, control the access of molecules to the surface of a field-effect transistor in a sensor device. Films and membranes with non-oriented channels have been prepared by depositing or growing zeolite(7-12) crystals on metal or metal-oxide supports(13-21); in one case(21), pre-grown crystals of an aluminophosphate zeolite were oriented by application of an electric field. Here we report the oriented growth of crystals of a zinco-phosphate zeolite on gold surfaces modified with metal phosphonate multilayer films. We attribute the high degree of orientation (>90%) to a strong affinity between the phosphonic acid groups of the phosphate multilayer and the (111) faces of the growing crystals.
C1 PURDUE UNIV,DEPT CHEM,W LAFAYETTE,IN 47907.
C3 Purdue University System; Purdue University
NR 29
TC 156
Z9 172
U1 0
U2 61
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 834
EP 836
DI 10.1038/368834a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700064
DA 2026-03-10
ER

PT J
AU NEOPHYTIDES, SG
   TSIPLAKIDES, D
   STONEHART, P
   JAKSIC, MM
   VAYENAS, CG
AF NEOPHYTIDES, SG
   TSIPLAKIDES, D
   STONEHART, P
   JAKSIC, MM
   VAYENAS, CG
TI ELECTROCHEMICAL ENHANCEMENT OF A CATALYTIC REACTION IN AQUEOUS-SOLUTION
SO NATURE
LA English
DT Article
ID oxidation
AB THE rates of many heterogeneous catalytic reactions between gaseous adsorbates on metal surfaces supported on solid electrolytes can be increased by applying a potential to the metal(1-8). This phenomenon, which has been reported previously at temperatures of 250-750 degrees C, has been shown(9) to be due to the electrochemically induced spillover of ions from the support onto the catalyst surface; the ions then act as promoters for the catalytic reaction. Here we report that a similar effect can be observed in aqueous solution at ambient temperatures. We studied the oxidation of H-2 on a platinum/graphite electrode immersed in aqueous KOH. Application of a positive potential of 1-2 V to the Pt electrode increased the rate of H-2 oxidation by up to 500%. We deduce that hydroxide ions are acting as promoters, and find that each ion supplied to the catalyst causes the oxidation of up to 20 hydrogen atoms. This kind of rate enhancement for heterogeneous catalytic reactions in solution may be of considerable technological value, for example in the electrochemical treatment of toxic organics(10) or the generation of useful industrial chemicals(4).
C1 STONEHART ASSOCIATES INC,MADISON,CT 06443.
RP NEOPHYTIDES, SG (corresponding author), UNIV PATRAS,INST CHEM ENGN & HIGH TEMP CHEM PROC,DEPT CHEM ENGN,GR-26500 PATRAI,GREECE.
NR 16
TC 127
Z9 133
U1 0
U2 45
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 45
EP 47
DI 10.1038/370045a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100052
DA 2026-03-10
ER

PT J
AU CALKINS, DJ
   SCHEIN, SJ
   TSUKAMOTO, Y
   STERLING, P
AF CALKINS, DJ
   SCHEIN, SJ
   TSUKAMOTO, Y
   STERLING, P
TI M-CONE AND L-CONE IN MACAQUE FOVEA CONNECT TO MIDGET GANGLION-CELLS BY DIFFERENT NUMBERS OF EXCITATORY SYNAPSES
SO NATURE
LA English
DT Article
ID bipolar cells; electron-microscopy; monkey retina; cat retina
AB VISUAL acuity depends on the fine-grained neural image set by the foveal cone mosaic(1-3). To preserve this spatial detail, cones transmit through non-divergent pathways: cone-->midget bipolar cell-->midget ganglion cell. Adequate gain must be established along each pathway; crosstalk and sources of variation between pathways must be minimized. These requirements raise fundamental questions regarding the synaptic connections: (1) how many synapses from bipolar to ganglion cell transmit a cone signal and with what degree of crosstalk between adjacent pathways; (2) how accurately these connections are reproduced across the mosaic; and (3) whether the midget circuits for middle (M) and long (L) wavelength sensitive cones are the same. We report here that the midget ganglion cell collects without crosstalk either 28 +/- 14 or 47 +/- 3 midget bipolar synapses. Two cone types are defined by this difference; being about equal in number and distributing randomly in small clusters of like type, they are probably M and L.
C1 UNIV CALIF LOS ANGELES,DEPT PSYCHOL,LOS ANGELES,CA 90024.
   HYOGO MED UNIV,DEPT ANAT,NISHINOMIYA,HYOGO 663,JAPAN.
C3 University of California System; University of California Los Angeles; Hyogo Medical University
RP CALKINS, DJ (corresponding author), UNIV PENN,DEPT NEUROSCI,PHILADELPHIA,PA 19104, USA.
NR 24
TC 167
Z9 187
U1 1
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 70
EP 72
DI 10.1038/371070a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100053
PM 8072528
DA 2026-03-10
ER

PT J
AU ELION, WJ
   MATTERS, M
   GEIGENMULLER, U
   MOOIJ, JE
AF ELION, WJ
   MATTERS, M
   GEIGENMULLER, U
   MOOIJ, JE
TI DIRECT DEMONSTRATION OF HEISENBERGS UNCERTAINTY PRINCIPLE IN A SUPERCONDUCTOR
SO NATURE
LA English
DT Article
ID josephson; junctions
AB A HEISENBERG uncertainty relation exists between any two noncommuting variables of a quantum-mechanical system. In a superconductor, two such variables are the number, n, of Cooper pairs and the phase, phi, of the superconducting wavefunction. Suppressing fluctuations in either variable should lead to enhanced fluctuations in the other(1,2). To demonstrate this effect, we have fabricated a structure in which the quantum-mechanical fluctuations in the phase bf a superconducting grain can be suppressed. We measure the supercurrent that Rows through two Josephson tunnel junctions of small capacitance that are connected to the grain. The capacitance of the grain is itself so small that the number of Cooper pairs is well defined-charge transport through the grain is possible only through quantum-mechanical fluctuations in n. The phase of the grain is coupled to a large superconducting reservoir such that the fluctuations in phi can be controllably suppressed. The enhanced fluctuations in n that result from this coupling give rise to a large increase in the supercurrent through the grain.
C1 DELFT INST MICROELECTR & SUBMICRON TECHNOL,2600 GA DELFT,NETHERLANDS.
C3 Delft University of Technology
RP ELION, WJ (corresponding author), DELFT UNIV TECHNOL,DEPT APPL PHYS,POB 5046,2600 GA DELFT,NETHERLANDS.
NR 13
TC 36
Z9 39
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 594
EP 595
DI 10.1038/371594a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900047
DA 2026-03-10
ER

PT J
AU VINEIS, P
   BARTSCH, H
   CAPORASO, N
   HARRINGTON, AM
   KADLUBAR, FF
   LANDI, MT
   MALAVEILLE, C
   SHIELDS, PG
   SKIPPER, P
   TALASKA, G
   TANNENBAUM, SR
AF VINEIS, P
   BARTSCH, H
   CAPORASO, N
   HARRINGTON, AM
   KADLUBAR, FF
   LANDI, MT
   MALAVEILLE, C
   SHIELDS, PG
   SKIPPER, P
   TALASKA, G
   TANNENBAUM, SR
TI GENETICALLY BASED N-ACETYLTRANSFERASE METABOLIC POLYMORPHISM AND LOW-LEVEL ENVIRONMENTAL EXPOSURE TO CARCINOGENS
SO NATURE
LA English
DT Article
ID exfoliated urothelial cells; hemoglobin adducts; dna adducts; urinary mutagenicity; cigarette smokers; smoking; acetylation; phenotype; cancer
AB THE metabolic activation or inactivation of carcinogens varies considerably in human populations, and is partly genetically determined(1,2). Inter-individual variability in the susceptibility to carcinogens may be particularly important at low degrees of environmental exposure. Examples of probable human carcinogens that present widespread low-dose exposures are environmental tobacco smoke and diesel exhaust(3,4). We have determined levels of DNA adducts in bladder cells and of 4-aminobiphenyl-haemoglobin adducts in 97 volunteers, together with the N-acetylation non-inducible phenotype, the corresponding genotype, and the levels of nicotine-cotinine in the urine. We find that among the slow acetylators, 4-aminobiphenyl adducts were higher than in rapid acetylators at low or null nicotine-cotinine levels, whereas the difference between slow and rapid acetylators was less evident at increasing nicotine-cotinine levels. The N-acetyltransferase genotype is highly predictive of the acetylation phenotype. Our results indicate that the clearance of low-dose carcinogens is decreased in the genetically based slow-acetylator phenotype. Such genetic modulation of low-dose environmental risks is relevant to 'risk assessment' procedures.
C1 MAIN HOSP,I-10126 TURIN,ITALY.
   GERMAN CANC RES CTR,D-69120 HEIDELBERG,GERMANY.
   NCI,GENET EPIDEMIOL BRANCH,ROCKVILLE,MD 20892.
   NCI,HUMAN CARCINOGENESIS LAB,BETHESDA,MD 20892.
   NATL CTR TOXICOL RES,JEFFERSON,AR 72079.
   UNIV MILAN,IST MED LAVORO,I-20122 MILAN,ITALY.
   INT AGCY RES CANC,F-69372 LYON,FRANCE.
   MIT,DEPT CHEM,CAMBRIDGE,MA 02139.
   UNIV CINCINNATI,DEPT ENVIRONM HLTH,CINCINNATI,OH.
C3 Helmholtz Association; German Cancer Research Center (DKFZ); National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI); National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI); US Food & Drug Administration (FDA); University of Milan; World Health Organization; International Agency for Research on Cancer (IARC); Massachusetts Institute of Technology (MIT); University System of Ohio; University of Cincinnati
RP VINEIS, P (corresponding author), UNIV TURIN,DIPARTIMENTO SCI BIOMED & ONCOL UMANA,CANC EPIDEMIOL UNIT,I-10126 TURIN,ITALY.
NR 15
TC 270
Z9 284
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 154
EP 156
DI 10.1038/369154a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100051
PM 7909916
DA 2026-03-10
ER

PT J
AU LI, XL
   NOLL, M
AF LI, XL
   NOLL, M
TI EVOLUTION OF DISTINCT DEVELOPMENTAL FUNCTIONS OF 3 DROSOPHILA GENES BY ACQUISITION OF DIFFERENT CIS-REGULATORY REGIONS
SO NATURE
LA English
DT Article
ID segment polarity genes; even-skipped protein; int-1 protooncogene; spatial expression; paired gene; pox-neuro; embryos; pattern; dna; embryogenesis
AB IT is generally accepted that the specific function of a gene depends on its coding sequence. The three paired-box and homeobox genes paired (prd), gooseberry (gsb) and gooseberry neuro (gsbn) have distinct developmental functions in Drosophila embryogenesis1-5. During the syncytial blastoderm stage, the pair-rule gene prd4,6 activates segment-polarity genes, such as gsb7, wingless (wg), and engrailed (en), in segmentally repeated stripes8. After germ-band extension, gsb maintains the expression of wg, which in turn specifies the denticle pattern by repressing a default state of ubiquitous denticle formation in the ventral epidermis9. In addition, gsb activates gsbn5, which is expressed mainly in the central nervous system2,3, suggesting that gsbn is involved in neural development. Here we show that, despite the functional difference and the considerably diverged coding sequence of these genes, their proteins have conserved the same function. The finding that the essential difference between genes may reside in their cis-regulatory regions exemplifies an important evolutionary mechanism of how function diversifies after gene duplication.
RP LI, XL (corresponding author), UNIV ZURICH,INST MOLEC BIOL 2,WINTERTHURERSTR 190,CH-8057 ZURICH,SWITZERLAND.
NR 36
TC 124
Z9 136
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 83
EP 87
DI 10.1038/367083a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500065
PM 7906390
DA 2026-03-10
ER

PT J
AU ROBERTS, SGE
   GREEN, MR
AF ROBERTS, SGE
   GREEN, MR
TI ACTIVATOR-INDUCED CONFORMATIONAL CHANGE IN GENERAL TRANSCRIPTION FACTOR TFIIB
SO NATURE
LA English
DT Article
ID rna polymerase-ii; functional domains; dna-binding
AB TRANSCRIPTIONAL activator proteins (activators) function, at least in part, by increasing preinitiation complex assembly (for reviews see refs 1-4). Previous studies have shown that an acidic activator forms a contact with the general transcription factor TFIIB (refs 5-7) and recruits it into the preinitiation complex(5,8,9). Mutational studies indicate that this interaction between the acidic activator and TFIIB is required for transcriptional stimulation(5-7,10,11). We show here that the acidic activator-TFIIB interaction has an additional function in preinitiation complex assembly. We provide evidence that in native TFIIB the amino- and carboxy-terminal domains are engaged in an intramolecular interaction. The acidic activator disrupts this intramolecular interaction to expose binding sites for general transcription factors that enter the preinitiation complex through association with TFIIB. Thus, the acidic activator induces a conformational change in TFIIB that drives preinitiation complex assembly forward.
RP ROBERTS, SGE (corresponding author), UNIV MASSACHUSETTS,MED CTR,HOWARD HUGHES MED INST,PROGRAM MOLEC MED,373 PLANTAT ST,WORCESTER,MA 01605, USA.
NR 24
TC 156
Z9 168
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 717
EP 720
DI 10.1038/371717a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300061
PM 7935820
DA 2026-03-10
ER

PT J
AU NOORDERMEER, J
   KLINGENSMITH, J
   PERRIMON, N
   NUSSE, R
AF NOORDERMEER, J
   KLINGENSMITH, J
   PERRIMON, N
   NUSSE, R
TI DISHEVELLED AND ARMADILLO ACT IN THE WINGLESS SIGNALING PATHWAY IN DROSOPHILA
SO NATURE
LA English
DT Article
ID polarity gene armadillo; protein; expression; product; encodes; embryogenesis; requirements; secretion; epidermis; hedgehog
AB THE Wnt genes encode conserved secreted proteins that play a role in normal development and tumorigenesis1,2. Little is known about the signal transduction pathways of Wnt gene products. One of the best characterized Wnt family members is the Drosophila segment polarity gene wingless3-6. We have investigated whether segment polarity genes with a wingless-like phenotype mediate the wingless signal. We used a wingless transgene controlled by a heat-shock promoter for genetic epistasis experiments. We show that wingless acts through dishevelled and armadillo to affect the expression of the homeobox gene engrailed and cuticle differentiation.
C1 STANFORD UNIV, HOWARD HUGHES MED INST, STANFORD, CA 94305 USA.
   STANFORD UNIV, DEPT DEV BIOL, STANFORD, CA 94305 USA.
   HARVARD UNIV, SCH MED, HOWARD HUGHES MED INST, BOSTON, MA 02115 USA.
   HARVARD UNIV, SCH MED, DEPT GENET, BOSTON, MA 02115 USA.
C3 Stanford University; Howard Hughes Medical Institute; Stanford University; Howard Hughes Medical Institute; Harvard University; Harvard Medical School; Harvard University; Harvard Medical School
NR 33
TC 340
Z9 419
U1 1
U2 15
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 80
EP 83
DI 10.1038/367080a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500064
PM 7906389
DA 2026-03-10
ER

PT J
AU IGARASHI, K
   KATAOKA, K
   ITOH, K
   HAYASHI, N
   NISHIZAWA, M
   YAMAMOTO, M
AF IGARASHI, K
   KATAOKA, K
   ITOH, K
   HAYASHI, N
   NISHIZAWA, M
   YAMAMOTO, M
TI REGULATION OF TRANSCRIPTION BY DIMERIZATION OF ERYTHROID FACTOR NF-E2 P45 WITH SMALL MAF PROTEINS
SO NATURE
LA English
DT Article
ID leucine zippers; messenger-rna; dna-binding; differentiation; expression; promoter; synthase; cells; gene; fos
AB TRANSCRIPTION factor NF-E2 is crucial for regulating erythroid-specific gene expression1. Cloning of the NF-E2 p45 protein has revealed that it contains a basic region-leucine zipper (b-zip) domain which associates with another unidentified protein (of relative molecular mass 18,000) to form functional NF-E2 (ref. 2). We show here that products of the maf proto-oncogene family3-5, MafF, MafG and MafK (the small Maf proteins) which possess a b-zip DNA-binding domain but lack a canonical transactivation domain3, directly control the DNA-binding properties of p45 by heterodimeric association with p45. Whereas homodimers of the small Maf proteins act as negative regulators, heterodimers composed of Maf and p45 support active transcription in vivo. These results indicate that one (or all) of the small Maf proteins is the second constituent chain required for NF-E2 activity, and that negative as well as positive regulation can be achieved through an NF-E2 site, depending on the equilibrium concentrations of p45 and the Maf proteins inside erythroid cells.
C1 TOHOKU UNIV,SCH MED,DEPT BIOCHEM,2-1 SEIRYOMACHI,AOBA KU,SENDAI,MIYAGI 980,JAPAN.
   JAPANESE FDN CANC RES,INST CANC,DEPT VIRAL ONCOL,TOSHIMA KU,TOKYO 170,JAPAN.
C3 Tohoku University; Japanese Foundation for Cancer Research
NR 22
TC 428
Z9 479
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 568
EP 572
DI 10.1038/367568a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300062
PM 8107826
DA 2026-03-10
ER

PT J
AU PARSELL, DA
   KOWAL, AS
   SINGER, MA
   LINDQUIST, S
AF PARSELL, DA
   KOWAL, AS
   SINGER, MA
   LINDQUIST, S
TI PROTEIN DISAGGREGATION MEDIATED BY HEAT-SHOCK PROTEIN HSP104
SO NATURE
LA English
DT Article
ID rna-polymerase; yeast-cells; dnak; binding; hsp70; chaperones; origin; repa
AB THE heat-inducible members of the Hsp100 (or Clp) family of proteins share a common function in helping organisms to survive extreme stress, but the basic mechanism through which these proteins function is not understood(1-5) Hsp104 protects cells against a variety of stresses, under many physiological conditions(6,7) and its function has been evolutionarily conserved, at least from Saccharomyces cerevisiae to Arabidopsis thaliana(25). Homology with the Escherichia coli ClpA protein suggests that Hsp104 may provide stress tolerance by helping to rid the tell of heat-denatured proteins through proteolysis(1). But genetic analysis indicates that Hsp104 may function like Hsp70 as a molecular chaperones(8). Here we investigate the role of Hsp104 in vivo using a temperature-sensitive Vibrio harveyi luciferase-fusion protein as a test substrate(9). We find that Hsp104 does not protect luciferase from thermal denaturation, nor does it promote proteolysis of luciferase. Rather, Hsp104 functions in a manner not previously described for other heat-shock proteins: it mediates the resolubilization of heat-inactivated luciferase from insoluble aggregates.
C1 UNIV CHICAGO, DEPT MOLEC GENET & CELL BIOL, CHICAGO, IL 60637 USA.
   UNIV CHICAGO, DEPT PATHOL, CHICAGO, IL 60637 USA.
   UNIV CHICAGO, HOWARD HUGHES MED INST, CHICAGO, IL 60637 USA.
C3 University of Chicago; University of Chicago; Howard Hughes Medical Institute; University of Chicago
NR 25
TC 775
Z9 909
U1 1
U2 52
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 475
EP 478
DI 10.1038/372475a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200060
PM 7984243
DA 2026-03-10
ER

PT J
AU PAGES, F
   RAGUENEAU, M
   ROTTAPEL, R
   TRUNEH, A
   NUNES, J
   IMBERT, J
   OLIVE, D
AF PAGES, F
   RAGUENEAU, M
   ROTTAPEL, R
   TRUNEH, A
   NUNES, J
   IMBERT, J
   OLIVE, D
TI BINDING OF PHOSPHATIDYLINOSITOL-3-OH KINASE TO CD28 IS REQUIRED FOR T-CELL SIGNALING
SO NATURE
LA English
DT Article
ID molecular-cloning; activation; expression; 3-kinase; identification; accumulation; proteins; subunit; homolog; system
AB THE engagement of CD28 with its ligand B7.1/CD80 results in potent costimulation of T-cell activation initiated through the CD3/T-cell receptor complex(1,2). The biochemical basis of CD28 costimulatory function is poorly understood. The signalling pathways used by CD28 are unlike those used by the CD3/T-cell receptor in that they are resistant to cyclosporin A and independent of changes in cyclic AMP concentrations(3). These differences suggest that each pathway provides unique biochemical information which is required for T-cell activation. We report here that CD28 becomes tyrosine-phosphorylated following interaction with B7.1/CD80, which induces formation of a complex with phosphatidylinositol-3-OH kinase, mediated by the SH2 domains of the p85 subunit of the kinase. Phosphatidylinositol-3-OH kinase is a heterodimer of this 85K regulatory subunit and a 110K catalytic subunit, and is a common substrate for most receptor tyrosine kinases and some cytokine receptors(4,5), binding through its SH2 domain to phosphotyrosine in the motif Tyr-X-X-Met in the CD28 sequence, which is highly conserved between human, mouse and rat(6-8) and lies in the intracellular domain. We show that CD28 mutants that have their kinase-binding site deleted or the tyrosine at position 173 substituted by phenylalanine do not associate with the kinase after CD28 stimulation and cannot stimulate production of interleukin-2. Our results suggest that phosphatidylinositol-3-OH kinase is critical for signalling by CD28.
C1 INSERM,U119,F-13009 MARSEILLE,FRANCE.
   SMITHKLINE BEECHAM PHARMACEUT,KING OF PRUSSIA,PA 19406.
C3 Institut National de la Sante et de la Recherche Medicale (Inserm); GlaxoSmithKline; Glaxosmithkline USA
NR 17
TC 363
Z9 457
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 327
EP 329
DI 10.1038/369327a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900052
PM 8183372
DA 2026-03-10
ER

PT J
AU YANG, Y
   HEEGER, AJ
AF YANG, Y
   HEEGER, AJ
TI A NEW ARCHITECTURE FOR POLYMER TRANSISTORS
SO NATURE
LA English
DT Article
ID polyaniline
AB THE transistor, in its various forms, is a three-terminal amplifying electronic device(1). Transistors are usually based on inorganic semiconductors, such as silicon or gallium arsenide(1), but there is increasing interest in the use of organic semiconductors(2-4), motivated by their structural flexibility and tunable electronic properties. The organic transistors fabricated to date have used a conventional 'field-effect' architecture; unfortunately, such devices involve relatively long conduction pathways which, owing to the low carrier mobilities of the organic materials, render them inherently slow. In an attempt to circumvent this problem, we have developed a different device geometry, more closely related to that of the vacuum-tube triode. The structure consists of a thin film of a semiconducting polymer sandwiched between two electrodes, with the third electrode-a layer of a porous metallic polymer(5)-embedded within the semiconductor. The third electrode plays a role similar to that of the grid in a vacuum tube, controlling the current flow between the two outermost electrodes. This thin-film architecture reduces the length of the conduction pathway, resulting in a relatively fast response time and, in contrast to conventional field-effect transistors, does not require lateral patterning.
RP YANG, Y (corresponding author), UNIAX CORP,5375 OVERPASS RD,SANTA BARBARA,CA 93111, USA.
NR 9
TC 285
Z9 357
U1 0
U2 76
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 344
EP 346
DI 10.1038/372344a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700048
DA 2026-03-10
ER

PT J
AU THALI, M
   BUKOVSKY, A
   KONDO, E
   ROSENWIRTH, B
   WALSH, CT
   SODROSKI, J
   GOTTLINGER, HG
AF THALI, M
   BUKOVSKY, A
   KONDO, E
   ROSENWIRTH, B
   WALSH, CT
   SODROSKI, J
   GOTTLINGER, HG
TI FUNCTIONAL ASSOCIATION OF CYCLOPHILIN-A WITH HIV-1 VIRIONS
SO NATURE
LA English
DT Article
ID immunodeficiency-virus type-1; cis-trans isomerase; binding-protein; cyclosporine-a; histocompatibility; replication; cells; gene
AB CYCLOPHILINS are a family of proteins that bind the immunosuppressant cyclosporin A, possess peptidyl-prolyl cis-trans isomerase activity, and assist in the folding of proteins(1-6). Human cyclophilins A and B are host cell proteins that bind specifically to the HIV-1 Gag polyprotein p55(gag) in vitro(7). Here we report that viral particles formed by p55(gag), in contrast to particles formed by the Gag polyproteins of other retroviruses, contain significant amounts of cyclophilin A. Sequences in the capsid domain of p55(gag) are both required and sufficient for the virion-association of cyclophilin A. The association of cyclophilin A with HIV-1 virions was inhibited in a dose-dependent manner by cyclosporin A as well as by SDZ NIM811 ([Melle-4] cyclosporin), a non-immunosuppressive analogue of cyclosporin A(8). Drug-induced reductions in virion-associated cyclophilin A levels were accompanied by reductions in virion infectivity, indicating that the association is functionally relevant. Moreover, SDZ NIM811 inhibited the replication of HIV-1 but was inactive against SIVIMAC, a primate immunodeficiency virus closely related to HIV-1, which does not incorporate cyclophilin A.
C1 HARVARD UNIV,SCH MED,DANA FARBER CANC INST,DIV HUMAN RETROVIROL,BOSTON,MA 02115.
   HARVARD UNIV,SCH MED,DEPT PATHOL,BOSTON,MA 02115.
   SANDOZ GMBH,FORSCHUNGSINST,A-1235 VIENNA,AUSTRIA.
   HARVARD UNIV,SCH MED,DEPT BIOL CHEM & MOLEC PHARMACOL,BOSTON,MA 02115.
C3 Harvard University; Harvard University Medical Affiliates; Dana-Farber Cancer Institute; Harvard Medical School; Harvard University; Harvard Medical School; Novartis; NOVARTIS AUSTRIA; Sandoz; Harvard University; Harvard Medical School
NR 23
TC 566
Z9 670
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 363
EP 365
DI 10.1038/372363a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700056
PM 7969495
DA 2026-03-10
ER

PT J
AU DEGIORGI, L
   BRICENO, G
   FUHRER, MS
   ZETTL, A
   WACHTER, P
AF DEGIORGI, L
   BRICENO, G
   FUHRER, MS
   ZETTL, A
   WACHTER, P
TI OPTICAL MEASUREMENTS OF THE SUPERCONDUCTING GAP IN SINGLE-CRYSTAL K3C60 AND RB3C60
SO NATURE
LA English
DT Article
ID infrared transmission; energy-gap; fullerenes; relaxation
AB THE mechanism of superconductivity in alkali-metal compounds of C-60 (refs 1, 2) remains controversial. Electron-pairing mechanisms based on electron-phonon coupling involving both low-frequency (intermolecular) vibrations(3) and high-frequency (intramolecular) modes(4,5)-the strong-coupling and weak-coupling cases respectively-have been proposed. These two mechanisms have different associated energy scales, which is reflected in the magnitude of the superconducting energy gap. Measurements of the gap for these compounds have been reported previously for powder samples(6-8), but are somewhat discrepant or ambiguous, perhaps owing to grain-size or grain-junction effects. Here we report measurements on large single-crystal samples of K3C60 and Rb3C60 using optical reflectivity. We obtain values for the reduced gap ratio, 2 Delta/k(B)T(c), of 3.44 and 3.45 respectively, consistent with predictions for a mechanism based on standard Bardeen-Cooper-Schrieffer (BCS) electron-phonon coupling to intramolecular modes.
C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720.
C3 University of California System; University of California Berkeley
RP DEGIORGI, L (corresponding author), ETH ZURICH,FESTKORPERPHYS LAB,CH-8093 ZURICH,SWITZERLAND.
NR 19
TC 51
Z9 51
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 541
EP 543
DI 10.1038/369541a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400042
DA 2026-03-10
ER

PT J
AU HOLLINGER, DY
   KELLIHER, FM
   SCHULZE, ED
   KOSTNER, BMM
AF HOLLINGER, DY
   KELLIHER, FM
   SCHULZE, ED
   KOSTNER, BMM
TI COUPLING OF TREE TRANSPIRATION TO ATMOSPHERIC-TURBULENCE
SO NATURE
LA English
DT Article
ID broad-leaved forest; xylem sap flow; stomatal responses; hydraulic signals; vegetation; potentials; kinetics; climate; canopy; light
AB UNDERSTANDING mass and energy exchange between vegetation and the atmosphere is essential for determining the future state of the climate system(1,2) and responses of plant communities. Plant water use is at present described by steady-state transport models(3,4), even though transport in the boundary layer is turbulent(5,6). This is especially true for forests, where the canopy air space is a chaotic environment where large turbulent events alternate with smaller-scale mixing(3,4,7). Here we demonstrate that the turbulent nature of the atmosphere affects plant processes. We propose that the dynamic nature of plant-atmosphere coupling represents a previously unrecognized feedback that influences plant water use and transport.
C1 MANAAKI WHENUA LANDCARE RES, CHRISTCHURCH, NEW ZEALAND.
   UNIV BAYREUTH, LEHRSTUHL PFLANZENOKOL, W-8580 BAYREUTH, GERMANY.
C3 Landcare Research - New Zealand; University of Bayreuth
NR 23
TC 42
Z9 44
U1 0
U2 23
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 60
EP 62
DI 10.1038/371060a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100049
DA 2026-03-10
ER

PT J
AU CORY, JS
   HIRST, ML
   WILLIAMS, T
   HAILS, RS
   GOULSON, D
   GREEN, BM
   CARTY, TM
   POSSEE, RD
   CAYLEY, PJ
   BISHOP, DHL
AF CORY, JS
   HIRST, ML
   WILLIAMS, T
   HAILS, RS
   GOULSON, D
   GREEN, BM
   CARTY, TM
   POSSEE, RD
   CAYLEY, PJ
   BISHOP, DHL
TI FIELD TRIAL OF A GENETICALLY IMPROVED BACULOVIRUS INSECTICIDE
SO NATURE
LA English
DT Article
ID recombinant baculovirus; neurotoxin gene; expression; construction; toxin
AB IMPROVEMENT of biological pesticides through genetic modification has enormous potential and the insect baculoviruses are particularly amenable to this approach(1,2). A key aim of genetic engineering is to increase their speed of kill, primarily by the incorporation of genes which encode arthropod or bacterially derived insect-selective toxins(3-11), insect hormones(12,13) or enzymes(14,15). We report here the first, to our knowledge, field trial of a genetically improved nuclear polyhedrosis virus of the alfalfa looper, Autographa californica (AcNPV) that expresses an insect-selective toxin gene (AaHIT) derived from the venom of the scorpion Androctonus australis(16-18). Previous laboratory assays with the cabbage looper, Trichoplusia ni, demonstrated a 25% reduction in time to death compared to the wild-type virus, but unaltered pathogenicity(6) and host range(19). In the field, the modified baculovirus killed faster, resulting in reduced crop damage and it appeared to reduce the secondary cycle of infection compared to the wild-type virus.
C1 ROUSSEL UCLAF,ENVIRONM HLTH,BERKAMSTEAD HP4 2DY,HERTS,ENGLAND.
RP CORY, JS (corresponding author), NERC,INST VIROL & ENVIRONM MICROBIOL,MANSFIELD RD,OXFORD OX1 3SR,ENGLAND.
NR 23
TC 159
Z9 176
U1 0
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 138
EP 140
DI 10.1038/370138a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400056
DA 2026-03-10
ER

PT J
AU MCCRAY, R
   LIN, DNC
AF MCCRAY, R
   LIN, DNC
TI IS THE RING AROUND SN1987A A PROTOSTELLAR DISK
SO NATURE
LA English
DT Article
ID emission-lines; sn-1987a; progenitor; evolution; supernova-1987a; nebulae; clouds; 1987a; stars; cores
AB ACCORDING to conventional wisdom(1-4), the ring around supernova 1987A is a product of winds from tile progenitor star, which should have produced a thin, dense, spherical shell(1). It was accordingly a surprise when images obtained by the Hubble Space Telescope(5-8) revealed that the gas is in fact disposed in a thin ring, with a radial velocity(9) much smaller than that predicted by theory. This could be explained by an asymmetry in the red giant wind(10-12), or by rotational flattening(13,14), but these explanations seem to us to be ad hoc, and have associated problems. Here we propose, instead, that the ring is the inner rim of a disk of gas that is left over from the time of formation of the progenitor star. The centre of the disk was evaporated by the ionizing radiation of the progenitor over its lifetime of about ten million years, leaving a ring-like structure. Our hypothesis naturally explains the ring's physical properties, and leads to the prediction that we should see the rest of the disk shortly after the supernova ejecta hit the ring in AD 1999 +/- 3.
C1 UNIV CALIF SANTA CRUZ,LICK OBSERV,SANTA CRUZ,CA 95064.
C3 University of California System; University of California Santa Cruz
RP MCCRAY, R (corresponding author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA.
NR 34
TC 31
Z9 32
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 378
EP 380
DI 10.1038/369378a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400048
DA 2026-03-10
ER

PT J
AU SHARKEY, J
   BUTCHER, SP
AF SHARKEY, J
   BUTCHER, SP
TI IMMUNOPHILINS MEDIATE THE NEUROPROTECTIVE EFFECTS OF FK506 IN FOCAL CEREBRAL-ISCHEMIA
SO NATURE
LA English
DT Article
ID calcineurin phosphatase-activity; cyclosporine-a; nitric-oxide; immunosuppressant fk506; glutamate neurotoxicity; lymphocytes-t; brain; complexes; ischemia; rapamycin
AB THE immunosuppressive action of the drug FK506 involves inhibition of calcineurin in T-lymphocytes by a complex of FK506 and an FK506 binding protein, FKBP 12(1,2), a member of the immunophilin protein family(3,4). The functional role of brain immunophilins is, however, unclear(5,6). We show here that FK506 is a powerful neuroprotective agent in an in vivo model of focal cerebral ischaemia when administered up to 60 min post-occlusion. The minimum effective neuroprotective dose is comparable with the immunosuppressant dose in humans(7), suggesting. that FK506 may have clinical potential for the treatment of stroke. Although the related immunosuppressants rapamycin and cyclosporin failed to reduce brain damage, the finding that rapamycin pretreatment blocked the effect of FK506 confirms a role for immunophilins in the neuroprotective mechanism.
RP SHARKEY, J (corresponding author), UNIV EDINBURGH,FUJISAWA INST NEUROSCI,DEPT PHARMACOL,EDINBURGH EH8 9JZ,MIDLOTHIAN,SCOTLAND.
NR 29
TC 439
Z9 480
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 336
EP 339
DI 10.1038/371336a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400053
PM 7522303
DA 2026-03-10
ER

PT J
AU DEHAENELAMBERTZ, G
   DEHAENE, S
AF DEHAENELAMBERTZ, G
   DEHAENE, S
TI SPEED AND CEREBRAL CORRELATES OF SYLLABLE DISCRIMINATION IN INFANTS
SO NATURE
LA English
DT Article
ID 1st year; perception; attention; brain; life
AB THE remarkable linguistic abilities of human neonates are well documented(1-5). Young infants can discriminate phonemes even if they are not used in their native language(2-4), an ability which regresses during the first year of life(4,5). This ability to discriminate is often studied by repeating a stimulus for several minutes until some behavioural response of the infant habituates, and later examining whether the response recovers when the stimulus is changed(6). This method, however, does not reveal how fast infants can detect phonetic changes, nor what brain mechanisms are involved. We describe here high-density recordings of event-related potentials in three-month-old infants listening to syllables whose first consonants differed in place of articulation Two processing stages, corresponding to an increasingly refined analysis of the auditory input, were identified and localised to the temporal lobes. A late frontal response to novelty was also observed. The infant brain recognizes a phonetic change in less than 400 ms.
C1 CNRS,SCI COGNIT & PSYCHOLINGUIST LAB,INSERM,F-75270 PARIS 06,FRANCE.
   EHESS,F-75270 PARIS 06,FRANCE.
C3 Institut National de la Sante et de la Recherche Medicale (Inserm); Centre National de la Recherche Scientifique (CNRS)
RP DEHAENELAMBERTZ, G (corresponding author), UNIV OREGON,INST COGNIT & DECIS SCI,EUGENE,OR 97405, USA.
NR 25
TC 252
Z9 278
U1 0
U2 23
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 292
EP 295
DI 10.1038/370292a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900063
PM 8035876
DA 2026-03-10
ER

PT J
AU WADDLE, DM
AF WADDLE, DM
TI MATRIX CORRELATION TESTS SUPPORT A SINGLE ORIGIN FOR MODERN HUMANS
SO NATURE
LA English
DT Article
ID hominid burial site; esr dates; israel; evolution
AB THE debate over human origins has focused on two competing theories. The single African origin model holds that anatomically modern Homo sapiens evolved in Africa 100,000-200,000 years ago. Members of this population migrated out of Africa, replacing archaic human groups through Asia and Europe, with racial differentiation occurring within the past 100,000 years1-3.  The alternative regional continuity model proposes continuous evolution over the past million years, with racial variation developing early, and similar modern human traits developing in all regions as the result of worldwide gene flow4-6. The persistence of specific morphological features within regions over the past million years supports regional continuity, whereas the identification of anatomically modern fossil specimens from Africa and the Levant 50-60,000 years before they are found elsewhere, provides support for a single origin. I give here the first quantitative test of the fossil evidence for each of these models. Results support a single African and/or Levantine origin for modern humans.
C1 SUNY STONY BROOK,DOCTORAL PROGRAM ANTHROPOL SCI,STONY BROOK,NY 11794.
C3 State University of New York (SUNY) System; Stony Brook University
NR 25
TC 78
Z9 80
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 452
EP 454
DI 10.1038/368452a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000062
PM 8133890
DA 2026-03-10
ER

PT J
AU MCMANUS, JF
   BOND, GC
   BROECKER, WS
   JOHNSEN, S
   LABEYRIE, L
   HIGGINS, S
AF MCMANUS, JF
   BOND, GC
   BROECKER, WS
   JOHNSEN, S
   LABEYRIE, L
   HIGGINS, S
TI HIGH-RESOLUTION CLIMATE RECORDS FROM THE NORTH-ATLANTIC DURING THE LAST INTERGLACIAL
SO NATURE
LA English
DT Article
ID greenland ice cores; sediments; events; gisp2; sand
AB THE two deep ice cores recovered by the GRIP(1) and GISP(2) projects at Summit, Greenland, agree in detail over the past 100,000 years(3) and demonstrate dramatic climate variability in the North Atlantic region during the last glacial, before the current period of Holocene stability. This glacial climate instability has subsequently been documented in the marine sedimentary record of surface-ocean conditions in the North Atlantic(4). Before 100 kyr ago the two ice core records are discrepant, however, casting doubt on whether the oxygen isotope fluctuations during the last interglacial (Eemian) seen in the GRIP core(1,5) represent a true climate signal. Here we present high-resolution records of foraminiferal assemblages and ice-rafted detritus from two North Atlantic cores for the interval 65 kyr to 135 kyr ago, extending the surface-ocean record back to the Eemian. The correlation between our records and the Greenland ice-core records is good throughout the period in which the two ice cores agree, suggesting a regionally coherent climate response. During the Eemian, our marine records show a more stable climate than that implied by the GRIP ice core, suggesting that localized phenomena may be responsible for the variability in the latter record during the Eemian.
C1 UNIV COPENHAGEN,NIELS BOHR INST,DEPT GEOPHYS,DK-2200 COPENHAGEN N,DENMARK.
   UNIV ICELAND,INST SCI,DEPT GEOPHYS,IS-107 REYKJAVIK,ICELAND.
   CNRS,CEA,CFR LAB,F-91198 GIF SUR YVETTE,FRANCE.
C3 University of Copenhagen; Niels Bohr Institute; University of Iceland; Universite Paris Saclay; CEA; Centre National de la Recherche Scientifique (CNRS)
RP MCMANUS, JF (corresponding author), COLUMBIA UNIV,LAMONT DOHERTY EARTH OBSERV,PALISADES,NY 10964, USA.
NR 25
TC 390
Z9 415
U1 0
U2 57
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 326
EP 329
DI 10.1038/371326a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400050
DA 2026-03-10
ER

PT J
AU GRUBB, BR
   PICKLES, RJ
   YE, H
   YANKASKAS, JR
   VICK, RN
   ENGELHARDT, JF
   WILSON, JM
   JOHNSON, LG
   BOUCHER, RC
AF GRUBB, BR
   PICKLES, RJ
   YE, H
   YANKASKAS, JR
   VICK, RN
   ENGELHARDT, JF
   WILSON, JM
   JOHNSON, LG
   BOUCHER, RC
TI INEFFICIENT GENE-TRANSFER BY ADENOVIRUS VECTOR TO CYSTIC-FIBROSIS AIRWAY EPITHELIA OF MICE AND HUMANS
SO NATURE
LA English
DT Article
ID ion-transport defect; chloride transport; transgenic mice; expression; therapy; invivo; model; cftr
AB THE success of adenoviral vectors for gene therapy of lung disease in cystic fibrosis (CF) depends on efficient transfer of the complementary DNA encoding the correct version of the cystic fibrosis transmembrane regulator (CFTR) to the affected columnar epithelial cells lining the airways of the lung. Pre-clinical studies in vitro suggest that low doses of adenovirus vectors carrying this CFTR cDNA fan correct defective Cl- transport in cultured human CF airway epithelia(1). Here He use mice carrying the disrupted CF gene(2) to test the efficacy of this transfer system in vivo. We find that even repeated high doses can only partially (50%) correct the CF defect in Cl- transport in vivo and do not correct the Na+ transport defect at all. We investigated this discrepancy between the in vivo and in vitro transfer efficiency using CF mouse and human samples, and found that it reflects a difference in the susceptibility to adenovirus-5 transduction of the epithelial cell types dosed in vivo (columnar) and in vitro (basal-cell-like). These studies indicate that more efficient adenoviral gene-transfer vectors and/or refinement of dosing strategies are needed for therapy of CF lung disease.
C1 UNIV PENN,INST HUMAN GENE THERAPY,PHILADELPHIA,PA 19104.
C3 University of Pennsylvania
RP GRUBB, BR (corresponding author), UNIV N CAROLINA,CTR CF PULM RES & TREATMENT,CHAPEL HILL,NC 27599, USA.
FU NIDDK NIH HHS [R01 DK047967] Funding Source: Medline
NR 28
TC 317
Z9 343
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 802
EP 806
DI 10.1038/371802a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800061
PM 7523956
DA 2026-03-10
ER

PT J
AU IVINSON, AJ
AF IVINSON, AJ
TI P16 AND FAMILIAL MELANOMA
SO NATURE
LA English
DT Article
AB It remains unclear just how big the latest player in the tumour-suppressor league will turn out to be. But p16 is not about to go away.
NR 10
TC 1
Z9 1
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 180
EP 180
DI 10.1038/371180a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100070
DA 2026-03-10
ER

PT J
AU IRIFUNE, T
AF IRIFUNE, T
TI ABSENCE OF AN ALUMINOUS PHASE IN THE UPPER PART OF THE EARTHS LOWER MANTLE
SO NATURE
LA English
DT Article
ID high-pressure phase; transformations; camgsi2o6
AB RECENT high-pressure experiments(1-3) suggest that the Earth's lower mantle is composed of MgSiO3 and CaSiO3 perovskites, (Mg, Fe)O magnesiowustite, and a minor but significant amount of aluminous phases, such as majorite garnet or an unidentified Al-rich phase. The stability of majorite garnet and the nature of any such aluminous phase, however, are controversial issues relevant to the mineralogy of the lower mantle(4-7). Here I report an experimental study of the phase transformations that occur in a pyrolite mantle composition with increasing pressure from 23 to 28 GPa (equivalent to similar to 650-770 km depth in the mantle). The results demonstrate that majorite garnet completely transforms to perovskite structures at pressures above 26 GPa (>720 km depth). Al2O3 is accommodated mainly in MgSiO3 perovskite, and no separate aluminous phase was observed at higher pressures, leading to the conclusion that the upper part of the Earth's lower mantle is composed only of two perovskites and magnesiowustite.
RP IRIFUNE, T (corresponding author), EHIME UNIV,DEPT EARTH SCI,MATSUYAMA,EHIME 790,JAPAN.
NR 25
TC 289
Z9 316
U1 1
U2 66
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 131
EP 133
DI 10.1038/370131a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400053
DA 2026-03-10
ER

PT J
AU ABRAHAMS, BF
   HOSKINS, BF
   MICHAIL, DM
   ROBSON, R
AF ABRAHAMS, BF
   HOSKINS, BF
   MICHAIL, DM
   ROBSON, R
TI ASSEMBLY OF PORPHYRIN BUILDING-BLOCKS INTO NETWORK STRUCTURES WITH LARGE CHANNELS
SO NATURE
LA English
DT Article
ID molecular-sieve; host
AB CRYSTAL engineering-the deliberate design and construction of crystal structures from molecular components-promises to provide solid-state materials with specific and useful chemical, mechanical, electronic or optical properties(1). In most of the molecular crystals considered so far, van der Waals forces and hydrogen bonding govern the crystal packing(2-7). Zeolites, pillared clays and related microporous materials, which have been studied extensively because their porous structures convey useful catalytic activity(8,9), can now also be 'engineered' to some extent(10,11). We are exploring ways(12-14) to construct channelled solids with very different chemical cal architectures and potentially different catalytic activity from those of zeolites. Here we show that porphyrin building blocks can be used to construct three-dimensional networks with the topology of the PtS structure, containing large channels. In our materials the channels are filled with solvent molecules, and crystalline order is lost on solvent removal. Nevertheless, the results show that it is possible to use simple molecular building blocks to engineer specific frameworks which, if they can be made robust, may offer new catalytic potential.
RP ABRAHAMS, BF (corresponding author), UNIV MELBOURNE,SCH CHEM,INORGAN SECT,PARKVILLE,VIC 3052,AUSTRALIA.
NR 26
TC 751
Z9 811
U1 8
U2 200
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 727
EP 729
DI 10.1038/369727a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100053
DA 2026-03-10
ER

PT J
AU HOOPER, JE
AF HOOPER, JE
TI DISTINCT PATHWAYS FOR AUTOCRINE AND PARACRINE WINGLESS SIGNALING IN DROSOPHILA EMBRYOS
SO NATURE
LA English
DT Article
ID cell-cell communication; hedgehog gene; patched gene; protein; transcription; secretion; product; expression; epidermis; mutations
AB Two secreted proteins, Wingless(1,2) and Hedgehog(3,4), instruct cell fates within the segmented epidermis of Drosophila embryos (reviewed in ref. 5). Wingless (Wg) is expressed by the most posterior cells in each parasegment; Hedgehog (Hh) is expressed in the most anterior cells of the next parasegment. Immediately after gastrulation, the two cell types are mutually dependent(6,7). Local Wg signalling stabilizes Hh expression(8-10) and local Hh signalling stabilizes Wg expression(11,12). Direct Wg autoregulation (autocrine signalling) is masked by its paracrine role in maintaining hh, which in turn maintains wg. I have used zeste-white3 (zw3)(13) and patched (ptc)(11,14) mutant backgrounds to uncouple genetically this positive-feedback loop and to study autocrine Wg signalling. I report here that direct Wg autoregulation differs from Wg signalling to adjacent cells in the importance of fused (fu), smoothened (smo) and cubitus interruptus (ci) relative to zw3 and armadillo (arm). I also find that Wg autoregulation during this early hh-dependent phase differs from later Wg autoregulation(15) by lack of gooseberry (gsb) participation.
RP HOOPER, JE (corresponding author), UNIV COLORADO, HLTH SCI CTR, DEPT CELLULAR & STRUCT BIOL, DENVER, CO 80262 USA.
NR 31
TC 120
Z9 133
U1 0
U2 1
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 461
EP 464
DI 10.1038/372461a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200056
PM 7984239
DA 2026-03-10
ER

PT J
AU ONO, K
   TSUJIMOTO, G
   SAKAMOTO, A
   ETO, K
   MASAKI, T
   OZAKI, Y
   SATAKE, M
AF ONO, K
   TSUJIMOTO, G
   SAKAMOTO, A
   ETO, K
   MASAKI, T
   OZAKI, Y
   SATAKE, M
TI ENDOTHELIN-A RECEPTOR MEDIATES CARDIAC INHIBITION BY REGULATING CALCIUM AND POTASSIUM CURRENTS
SO NATURE
LA English
DT Article
ID gene-related peptide; vasoconstrictor peptide; cells; cloning; heart; cdna; expression; subtypes; myocytes; binding
AB VOLTAGE-SENSITIVE ion channels play fundamental roles in the regulation of cardiac function by various neurotransmitters(1,2). Endothelins(3) have strong positive inotropic(4) and chronotropic(5) effects, for,which recent studies have implicated various intracellular mechanisms(6,7). However, very little is known about the underlying ion-channel regulation by the peptide. We report here that endothelin-1 consistently hyperpolarizes the membrane and shortens the duration of the action potential in mammalian atrial myocytes, leading to suppression of electrical excitability of the heart. Endothelin-1, but not endothelin(3), inhibited the L-type calcium current by decreasing cyclic AMP accumulation and activated the muscarinic potassium current by stimulating a pertussis toxin-sensitive GTP-binding protein. Consistent with these results, endothelin-1 strongly reduced the heart rate when it was increased by beta-adrenoceptor stimulation. These effects were blocked by an ET(A) (endothelin-1-selective) receptor-selective antagonist, BQ123 (refs 8-11). The ET(A) receptor-mediated regulation of cardiac ion channels gives new insight into our understanding of the physiological and pathophysiological roles of endothelins in the control of cardiac function.
C1 NATL CHILDRENS MED RES CTR,DIV MOLEC & CELLULAR PHARMACOL,SETAGAYA KU,TOKYO 154,JAPAN.
   KYOTO UNIV,FAC MED,DEPT PHARMACOL,SAKYO KU,KYOTO 60601,JAPAN.
C3 National Center for Child Health & Development - Japan; Kyoto University
RP ONO, K (corresponding author), NATL INST HLTH SCI,DIV CHEM PHARMACOL & PHYTOCHEM,SETAGAYA KU,1-18-1 KAMI YOHGA,TOKYO 158,JAPAN.
NR 27
TC 145
Z9 150
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 301
EP 304
DI 10.1038/370301a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900066
PM 8035879
DA 2026-03-10
ER

PT J
AU CHRISTOFORI, G
   NAIK, P
   HANAHAN, D
AF CHRISTOFORI, G
   NAIK, P
   HANAHAN, D
TI A 2ND SIGNAL SUPPLIED BY INSULIN-LIKE GROWTH-FACTOR-II IN ONCOGENE-INDUCED TUMORIGENESIS
SO NATURE
LA English
DT Article
ID beta-cell tumors; transgenic mice; induction; tissue; protein; lineage; gene
AB TRANSGENIC mice expressing the simian virus-40 large T-antigen (Tag) under the control of the insulin gene regulatory region offer a useful model for tumorigenesis(1,2). All the islets of Langerhans express Tag, although there is at first no aberrant proliferation. Over half of the islets become hyperplastic, however, and neovascularization of a further subset (about 10%)(3) leads eventually to formation of highly vascularized solid tumours in 1-2% of islets by about 14 weeks of age. Here we show that the initial proliferative switch is correlated with focal activation of insulin-like growth factor II (IGF-II). Transfection with an antisense oligonucleotide to the IGF-II messenger RNA interferes with tumour cell proliferation in vitro, and transgenic mice homozygous for a disruption of the IGF-II gene develop tumours with reduced malignancy and a higher incidence of apoptosis. Several signals, in this case including an oncoprotein and a growth/survival factor, thus appear to be needed to elicit hyperproliferation.
C1 UNIV CALIF SAN FRANCISCO,DEPT BIOCHEM & BIOPHYS,SAN FRANCISCO,CA 94143.
   UNIV CALIF SAN FRANCISCO,HORMONE RES INST,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco; University of California System; University of California San Francisco
NR 24
TC 388
Z9 419
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 414
EP 418
DI 10.1038/369414a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400061
PM 7910953
DA 2026-03-10
ER

PT J
AU ROSENZWEIG, C
   PARRY, ML
AF ROSENZWEIG, C
   PARRY, ML
TI POTENTIAL IMPACT OF CLIMATE-CHANGE ON WORLD FOOD-SUPPLY
SO NATURE
LA English
DT Article
ID carbon-dioxide; responses; model
AB A global assessment of the potential impact of climate change on world food supply suggests that doubling of the atmospheric carbon dioxide concentration will lead to only a small decrease in global crop production. But developing countries are likely to bear the brunt of the problem, and simulations of the effect of adaptive measures by farmers imply that these will do little to reduce the disparity between developed and developing countries.
C1 GODDARD INST SPACE STUDIES,NEW YORK,NY 10025.
   UNIV OXFORD,ENVIRONM CHANGE UNIT,OXFORD OX1 3TB,ENGLAND.
C3 National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center; Goddard Institute for Space Studies; University of Oxford
RP ROSENZWEIG, C (corresponding author), COLUMBIA UNIV,2800 BROADWAY,NEW YORK,NY 10025, USA.
NR 23
TC 1147
Z9 1443
U1 7
U2 396
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 133
EP 138
DI 10.1038/367133a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000049
DA 2026-03-10
ER

PT J
AU ROBERTSON, DE
   FARID, RS
   MOSER, CC
   URBAUER, JL
   MULHOLLAND, SE
   PIDIKITI, R
   LEAR, JD
   WAND, AJ
   DEGRADO, WF
   DUTTON, PL
AF ROBERTSON, DE
   FARID, RS
   MOSER, CC
   URBAUER, JL
   MULHOLLAND, SE
   PIDIKITI, R
   LEAR, JD
   WAND, AJ
   DEGRADO, WF
   DUTTON, PL
TI DESIGN AND SYNTHESIS OF MULTI-HEME PROTEINS
SO NATURE
LA English
DT Article
ID electron-paramagnetic resonance; blodgett monolayer films; viridis reaction center; cytochrome-c; rhodopseudomonas-viridis; rhodobacter-sphaeroides; desulfovibrio-vulgaris; transfer mechanisms; redox; complex
AB A water-soluble, 62-residue, di-alpha-helical peptide has been synthesized which accommodates two bis-histidyl haem groups. The peptide assembles into a four-helix dimer with 2-fold symmetry and four parallel haems that closely resemble native haems in their spectral and electro-chemical properties, including haem-haem redox interaction. This protein is an essential intermediate in the synthesis of molecular 'maquettes', a novel class of simplified versions of the metalloproteins involved in redox catalysis and in energy conversion in respiratory and photosynthetic electron transfer.
C1 UNIV ILLINOIS,SCH CHEM SCI,DEPT BIOCHEM,URBANA,IL 61801.
   DUPONT CO INC,DEPT CENT RES & DEV,WILMINGTON,DE 19880.
C3 University of Illinois System; University of Illinois Urbana-Champaign; DuPont; DuPont USA
RP ROBERTSON, DE (corresponding author), UNIV PENN,DEPT BIOCHEM & BIOPHYS,JOHNSON RES FDN,PHILADELPHIA,PA 19104, USA.
NR 49
TC 481
Z9 542
U1 1
U2 74
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 425
EP 431
DI 10.1038/368425a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000053
PM 8133888
DA 2026-03-10
ER

PT J
AU MILANI, A
   FARINELLA, P
AF MILANI, A
   FARINELLA, P
TI THE AGE OF THE VERITAS ASTEROID FAMILY DEDUCED BY CHAOTIC CHRONOLOGY
SO NATURE
LA English
DT Article
ID behavior; rates
AB ASTEROID families are groups of objects produced in disruptive collisions of a parent body. Although family members are widely dispersed in real space, they cluster in the parameter space defined by their so-called proper elements, and can thus be distinguished from the background asteroid population(1-3). For most asteroids, these parameters are very close to being invariants of motion and families are still apparent billions of years after their formation(4,5). But these parameters undergo chaotic diffusion, and in some cases the rate of diffusion might be large enough that a family member exits from the region of proper-element space occupied by the family after a characteristic time which is shorter than the lifetime of the Solar System. In this case, the characteristic time should provide an approximate upper bound to the age of the family. Here we use this 'chaotic chronology' method to estimate the lifetime of the unusually compact Veritas family. Calculations of the evolution of the proper elements of the family show that two members (including the largest, 490 Veritas) wander outside the borders of the family on a timescale of about 50 Myr, indicating that the family has an age of less than this.
RP MILANI, A (corresponding author), UNIV PISA,DIPARTIMENTO MATEMAT,GRP MECCAN SPAZIALE,VIA BUONARROTI 2,I-56127 PISA,ITALY.
NR 25
TC 53
Z9 56
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 40
EP 42
DI 10.1038/370040a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100050
DA 2026-03-10
ER

PT J
AU BRANDEIS, M
   FRANK, D
   KESHET, I
   SIEGFRIED, Z
   MENDELSOHN, M
   NEMES, A
   TEMPER, V
   RAZIN, A
   CEDAR, H
AF BRANDEIS, M
   FRANK, D
   KESHET, I
   SIEGFRIED, Z
   MENDELSOHN, M
   NEMES, A
   TEMPER, V
   RAZIN, A
   CEDAR, H
TI SP1 ELEMENTS PROTECT A CPG ISLAND FROM DE-NOVO METHYLATION
SO NATURE
LA English
DT Article
ID dna methylation; transcription factor; denovo methylation; mouse embryo; gene; promoter; cells; demethylation; patterns; tissue
AB ANIMAL somatic cell DNA is characterized by a bimodal pattern of methylation: tissue-specific genes are methylated in most cell types whereas housekeeping genes have 5' CpG islands which are constitutively unmethylated(1,2). Because methyl moieties derived from the gametes are erased in the morula and early blastula(3), this profile must be re-established in every generation; this is apparently accomplished by a wave of non-CpG island de novo methylation that occurs at implantation(4). Using transfection into embryonic stem cells and transgenic mice as a model system, we now show that Sp1 elements play a key role in protecting a CpG island in the adenine phosphoribosyltransferase (APRT) gene from de novo methylation. This recognition mechanism represents a critical step in embryogenesis; as it is responsible for setting up the correct genome methylation pattern which, in turn, is involved in regulating basal gene expression in the organism(5).
C1 TECHNION ISRAEL INST TECHNOL, BRUCE RAPPAPORT FAC MED, DEPT BIOCHEM, IL-31096 HAIFA, ISRAEL.
   COLUMBIA UNIV, SCH MED, CTR NEUROBIOL & BEHAV, NEW YORK, NY 10032 USA.
C3 Technion Israel Institute of Technology; Rappaport Faculty of Medicine; Columbia University
RP BRANDEIS, M (corresponding author), HEBREW UNIV JERUSALEM, SCH MED, DEPT CELLULAR BIOCHEM, IL-91120 JERUSALEM, ISRAEL.
NR 28
TC 643
Z9 730
U1 0
U2 25
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 435
EP 438
DI 10.1038/371435a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500048
PM 8090226
DA 2026-03-10
ER

PT J
AU BARVAINIS, R
   TACCONI, L
   ANTONUCCI, R
   ALLOIN, D
   COLEMAN, P
AF BARVAINIS, R
   TACCONI, L
   ANTONUCCI, R
   ALLOIN, D
   COLEMAN, P
TI EXTREMELY STRONG CARBON-MONOXIDE EMISSION FROM THE CLOVERLEAF QUASAR AT A REDSHIFT OF 2.5
SO NATURE
LA English
DT Article
ID galaxy iras 10214+4724; radio-quiet quasars; co emission; infrared galaxy; molecular gas; detections; h1413+117; origin; models
AB GALAXIES at high redshift are very faint and difficult to study at optical and near-infrared wavelengths, but detection of far-infrared emission(1) and molecular gas(2,3) in a galaxy at redshift z approximate to 2.3 has suggested that their early evolution may be investigated by these means instead. The host galaxies of quasars are promising candidates for these observations, particularly as quasars might be triggered by interactions and mergers between galaxies(4,5) which result in dust- and gas-rich systems. The Cloverleaf, a gravitationally lensed quasar, has far-infrared/submillimetre emission indicating a substantial dust content(6), and therefore potentially a large amount of gas. Here we report the detection of carbon monoxide emission from the Cloverleaf, which we interpret as indicating a mass of molecular gas that is comparable to the total dynamical mass of the host galaxy, and which is consistent with the total baryonic content of a present-day luminous galaxy. This suggests that, although some processing of gas through stars has taken place in the Cloverleaf at a lookback time of 85% of the current age of the Universe, much of the future stellar content has yet to be formed.
C1 MAX PLANCK INST EXTRATERR PHYS, D-85748 GARCHING, GERMANY.
   UNIV CALIF SANTA BARBARA, DEPT PHYS, SANTA BARBARA, CA 93106 USA.
   OBSERV PARIS, CNRS, URA 173, F-92195 MEUDON, FRANCE.
   KAPTEYN ASTRON INST, 9700 AV GRONINGEN, NETHERLANDS.
C3 Max Planck Society; University of California System; University of California Santa Barbara; Centre National de la Recherche Scientifique (CNRS); Universite PSL; Observatoire de Paris; University of Groningen; Kapteyn Astronomical Institute
RP BARVAINIS, R (corresponding author), MIT, HAYSTACK OBSERV, WESTFORD, MA 01886 USA.
NR 22
TC 130
Z9 132
U1 0
U2 3
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 586
EP 588
DI 10.1038/371586a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900044
DA 2026-03-10
ER

PT J
AU HIURA, H
   EBBESEN, TW
   FUJITA, J
   TANIGAKI, K
   TAKADA, T
AF HIURA, H
   EBBESEN, TW
   FUJITA, J
   TANIGAKI, K
   TAKADA, T
TI ROLE OF SP(3) DEFECT STRUCTURES IN GRAPHITE AND CARBON NANOTUBES
SO NATURE
LA English
DT Article
ID c-60; form
AB THE discovery of fullerenes1,2 and carbon nanotubes3,4 has led to the realization that it should be possible to tailor the properties of graphitic sheets if their geometry can be controlled5-7. In exploring these possibilities, we have found that the folding and tearing of graphitic sheets follow well defined patterns which seem to be governed by the formation of sp3-like line defects in the sp2 graphitic network. Our studies with the atomic force microscope and scanning tunnelling microscope reveal that these folds and tears occur preferentially along the symmetry axes of graphite, and that 'ripples' are observed in the curved portions of the folds. We also see ripples in deformed carbon nanotubes. They lie along the directions for which sp3-like line defects can form most easily to relieve strain. Our ab initio molecular orbital calculations indicate that the ripples stabilize the pi-electronic energy in the bent structures with the total energy balance being determined by the amount of nuclear repulsion. These results provide insight into the geometries that graphitic structures will preferentially accommodate, and the properties that might ensue.
C1 NEC CORP LTD, FUNDAMENTAL RES LABS, 34 MIUKIGAOKA, TSUKUBA 305, JAPAN.
C3 NEC Corporation
NR 13
TC 222
Z9 250
U1 1
U2 87
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 148
EP 151
DI 10.1038/367148a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000052
DA 2026-03-10
ER

PT J
AU FRITZ, M
   BELCHER, AM
   RADMACHER, M
   WALTERS, DA
   HANSMA, PK
   STUCKY, GD
   MORSE, DE
   MANN, S
AF FRITZ, M
   BELCHER, AM
   RADMACHER, M
   WALTERS, DA
   HANSMA, PK
   STUCKY, GD
   MORSE, DE
   MANN, S
TI FLAT PEARLS FROM BIOFABRICATION OF ORGANIZED COMPOSITES ON INORGANIC SUBSTRATES
SO NATURE
LA English
DT Article
AB THE study of biomineralization is inspiring new approaches to the controlled fabrication of synthetic materials such as nanoparticles, polymer-mineral composites and templated crystals(1-3). Although this biomimetic approach is gaining momentum, the biological mechanisms involved in biomineralization remain relatively unexplored. One major reason for this is the difficulty of analysing biomineralization processes in their native dynamic state. Here we demonstrate that a highly organized composite material-a 'flat pearl'-can be biofabricated on disks of glass, mica and MoS2 inserted between the mantle and shell of Haliotis rufescens (red abalone). We shove that the construction of this material is spatially and temporally regulated and proceeds through a developmental sequence that closely resembles that at the growth front of the natural shell. Recognition of the implanted inorganic surfaces by mantle cells apparently governs a switch, perhaps genetically controlled, from aragonite to calcite biomineralization. Once a partially oriented calcite-protein primer layer has been deposited, there is a switch back to the nucleation and assembly of columnar stacks of highly ordered aragonitic nacre. Thus the presence of an inorganic surface between the mantle and shell of the organism triggers a change in the nature of the mineral phase deposited.
C1 UNIV CALIF SANTA BARBARA,INST MARINE SCI,CTR MARINE BIOTECHNOL,SANTA BARBARA,CA 93106.
   UNIV CALIF SANTA BARBARA,DEPT PHYS,SANTA BARBARA,CA 93106.
   UNIV CALIF SANTA BARBARA,DEPT CHEM,SANTA BARBARA,CA 93106.
   UNIV CALIF SANTA BARBARA,MAT RES LAB,SANTA BARBARA,CA 93106.
   UNIV BATH,SCH CHEM,BATH BA2 7AY,AVON,ENGLAND.
C3 University of California System; University of California Santa Barbara; University of California System; University of California Santa Barbara; University of California System; University of California Santa Barbara; University of California System; University of California Santa Barbara; University of Bath
NR 20
TC 219
Z9 254
U1 1
U2 112
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 49
EP 51
DI 10.1038/371049a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100045
DA 2026-03-10
ER

PT J
AU PICOT, D
   LOLL, PJ
   GARAVITO, RM
AF PICOT, D
   LOLL, PJ
   GARAVITO, RM
TI THE X-RAY CRYSTAL-STRUCTURE OF THE MEMBRANE-PROTEIN PROSTAGLANDIN-H(2) SYNTHASE-1
SO NATURE
LA English
DT Article
ID higher oxidation-states; cytochrome-c peroxidase; endoperoxide synthase; h synthase; complementary-dna; cyclooxygenase; enzyme; spectroscopy; resolution; catalysis
AB The three-dimensional structure of prostaglandin H-2 synthase-1, an integral membrane Protein, has been determined at 3.5 angstrom resolution by X-ray crystallography. This bifunctional enzyme comprises three independent folding units: an epidermal growth factor domain, a membrane-binding motif and an enzymatic domain. Two adjacent but spatially distinct active sites were found for its haem-dependent peroxidase and cyclooxygenase activities. The cyclooxygenase active site is created by a long, hydrophobic channel that is the site of non-steroidal anti-inflammatory drug binding. The conformation of the membrane-binding motif strongly suggests that the enzyme integrates into only one leaflet of the lipid bilayer and is thus a monotopic membrane protein.
C1 UNIV CHICAGO, DEPT BIOCHEM & MOLEC BIOL, 920 E 58TH ST, CHICAGO, IL 60637 USA.
C3 University of Chicago
NR 49
TC 1140
Z9 1264
U1 0
U2 74
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 243
EP 249
DI 10.1038/367243a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400046
PM 8121489
DA 2026-03-10
ER

PT J
AU GORODETSKII, V
   LAUTERBACH, J
   ROTERMUND, HH
   BLOCK, JH
   ERTL, G
AF GORODETSKII, V
   LAUTERBACH, J
   ROTERMUND, HH
   BLOCK, JH
   ERTL, G
TI COUPLING BETWEEN ADJACENT CRYSTAL PLANES IN HETEROGENEOUS CATALYSIS BY PROPAGATING REACTION-DIFFUSION WAVES
SO NATURE
LA English
DT Article
ID desorption spectroscopy; adsorption; kinetics; hydrogen; microscopy; surfaces; h-2
AB UNDERSTANDING Of the mechanisms and kinetics of heterogeneous catalytic reactions has come largely from the study of gas-solid interactions on well defined single-crystal surfaces(1,2). But real catalysts usually consist of nanometre-sized particles on which several different crystal planes are exposed. In general, it has been assumed that their properties can be regarded as a superposition of the contributions from each individual structural element. Here we show that this assumption may be invalid, even qualitatively, in certain cases. We have studied the oxidation of hydrogen on platinum surfaces at low pressure and room temperature. On a macroscopic Pt(100) single crystal the reaction reaches a steady state with a uniform distribution of adsorbates. But on the platinum tip of a field ion microscope, on which several different crystal planes are exposed, the reaction has a very different character. The tip contains a region of the (100) plane just 40 nm in diameter, on which the reaction rate displays sustained temporal oscillations. This effect is associated with continuously changing distributions of the adsorbed species in the form of propagating waves, which are generated by coupling of reactions occurring on adjacent crystal planes. This kind of interaction between different crystal planes may exert a profound influence on the kinetics of heterogeneous catalysis.
RP GORODETSKII, V (corresponding author), MAX PLANCK GESELL,FRITZ HABER INST,FARADAYWEG 4-6,D-14195 BERLIN,GERMANY.
NR 22
TC 148
Z9 153
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 276
EP 279
DI 10.1038/370276a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900057
DA 2026-03-10
ER

PT J
AU BROWN, P
   CEPLECHA, Z
   HAWKES, RL
   WETHERILL, G
   BEECH, M
   MOSSMAN, K
AF BROWN, P
   CEPLECHA, Z
   HAWKES, RL
   WETHERILL, G
   BEECH, M
   MOSSMAN, K
TI THE ORBIT AND ATMOSPHERIC TRAJECTORY OF THE PEEKSKILL METEORITE FROM VIDEO RECORDS
SO NATURE
LA English
DT Article
ID fireballs; network
AB ON 9 October 1992, a bright fireball appeared over West Virginia, travelled some 700 km in a northeasterly direction, and culminated in at least one impact: a 12.4-kg ordinary chondrite was recovered in Peekskill, New York(1). Fortuitously, the event was captured on several video recordings, which provide a detailed record of both the fragmentation of the object and related atmospheric effects. These are the first motion pictures of a fireball from which a meteorite has been recovered. We report here the preliminary analysis of 14 video recordings of the event, from which we determine the ground path and the original orbit of the object.
C1 UNIV WESTERN ONTARIO, DEPT ASTRON, LONDON N6A 3K7, ON, CANADA.
   ACAD SCI CZECH REPUBLIC, INST ASTRON, ONDREJOV OBSERV, CS-25165 ONDREJOV, CZECH REPUBLIC.
   MT ALLISON UNIV, DEPT PHYS ENGN & GEOL, SACKVILLE E0A 3C0, NB, CANADA.
   CARNEGIE INST WASHINGTON, DEPT TERR MAGNETISM, WASHINGTON, DC 20015 USA.
C3 Western University (University of Western Ontario); Czech Academy of Sciences; Astronomical Institute of the Czech Academy of Sciences; Mount Allison University; Carnegie Institution for Science
RP BROWN, P (corresponding author), UNIV WESTERN ONTARIO, DEPT PHYS, LONDON N6A 3K7, ON, CANADA.
NR 13
TC 106
Z9 110
U1 0
U2 4
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 624
EP 626
DI 10.1038/367624a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800046
DA 2026-03-10
ER

PT J
AU GOGOTSI, YG
   YOSHIMURA, M
AF GOGOTSI, YG
   YOSHIMURA, M
TI FORMATION OF CARBON-FILMS ON CARBIDES UNDER HYDROTHERMAL CONDITIONS
SO NATURE
LA English
DT Article
ID new-hampshire; thin-film; graphite; equilibrium; fibers
AB CARBON films find applications in a wide range of fields, ranging from microelectronics to materials science(1). In ceramic matrix composites they confer the high strength and toughness needed for applications in aerospace, nuclear and automotive engineering(2). Chemical vapour deposition is traditionally used to prepare carbon films, but it is relatively expensive, and not easily adapted to coating samples in the form of whiskers, platelets or powders. Here we report that silicon carbide, the most common component of composite ceramics, can be coated with carbon films of nanometre to micrometre thickness by hydrothermal treatment at 300-800 degrees C. We have applied the technique to SiC fibres, powders, platelets and single crystals, as well as to other carbides. Our method should provide a general and inexpensive route to high-toughness composites and lubricating coatings.
C1 TOKYO INST TECHNOL,ENGN MAT RES LAB,MIDORI KU,YOKOHAMA 227,JAPAN.
C3 Institute of Science Tokyo; Tokyo Institute of Technology
NR 22
TC 160
Z9 171
U1 0
U2 67
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 628
EP 630
DI 10.1038/367628a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800048
DA 2026-03-10
ER

PT J
AU SONDEK, J
   LAMBRIGHT, DG
   NOEL, JP
   HAMM, HE
   SIGLER, PB
AF SONDEK, J
   LAMBRIGHT, DG
   NOEL, JP
   HAMM, HE
   SIGLER, PB
TI GTPASE MECHANISM OF GPROTEINS FROM THE 1.7-ANGSTROM CRYSTAL-STRUCTURE OF TRANSDUCIN ALPHA-CENTER-DOT-GDP-CENTER-DOT-ALF4(-)
SO NATURE
LA English
DT Article
ID h-ras p21; x-ray; hydrolysis; protein; mutants; activation; inhibition; mutations; aluminum; fluoride
AB ALUMINIUM fluoride (AlF4-) activates members of the heterotrimeric G-protein (G(alpha beta gamma)) family(1,2) by binding to inactive G(alpha).GDP near the site occupied by the gamma-phosphate in G(alpha).GTP (ref. 3). Here we describe the crystal structure of transducin alpha.GDP activated with aluminium fluoride (G(t alpha).GDP.AlF4-.H2O) at 1.7 Angstrom, a resolution sufficient to establish the coordination geometry of the bound aluminium fluoride as well as the extensive network of direct and water-mediated interactions that stabilize it. These observations are derived from three independent representations in the asymmetric unit, eliminating any chance of drawing conclusions based on stereochemistry imposed by crystal packing. Surprisingly, aluminium fluoride activates G(alpha).GDP by binding with a geometry resembling a pentavalent intermediate for GTP hydrolysis. The stabilizing interactions involve not only residues that interact with the gamma-phosphate in G(t alpha).GTP gamma S, but also conserved residues essential for GTPase activity. Thus the G(t alpha).GDP.AlF4-.H2O structure provides new insight into the mechanism of GTP hydrolysis.
C1 YALE UNIV,BOYER CTR MOLEC MED,DEPT MOLEC BIOPHYS & BIOCHEM,NEW HAVEN,CT 06510.
   YALE UNIV,BOYER CTR MOLEC MED,HOWARD HUGHES MED INST,NEW HAVEN,CT 06510.
   UNIV ILLINOIS,DEPT PHYSIOL & BIOPHYS,CHICAGO,IL 60680.
   UNIV SASSARI,IST FISIOL GEN & CHIM BIOL,I-07100 SASSARI,ITALY.
C3 Yale University; Howard Hughes Medical Institute; Yale University; University of Illinois System; University of Illinois Chicago; University of Illinois Chicago Hospital; University of Sassari
NR 30
TC 550
Z9 609
U1 1
U2 25
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 276
EP 279
DI 10.1038/372276a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900054
PM 7969474
DA 2026-03-10
ER

PT J
AU LAPIDOT, T
   SIRARD, C
   VORMOOR, J
   MURDOCH, B
   HOANG, T
   CACERESCORTES, J
   MINDEN, M
   PATERSON, B
   CALIGIURI, MA
   DICK, JE
AF LAPIDOT, T
   SIRARD, C
   VORMOOR, J
   MURDOCH, B
   HOANG, T
   CACERESCORTES, J
   MINDEN, M
   PATERSON, B
   CALIGIURI, MA
   DICK, JE
TI A CELL INITIATING HUMAN ACUTE MYELOID-LEUKEMIA AFTER TRANSPLANTATION INTO SCID MICE
SO NATURE
LA English
DT Article
ID immune-deficient mice; bone-marrow; progenitor cells; leukemia; hematopoiesis; differentiation; culture; growth; mouse
AB MOST human acute myeloid leukaemia (AML) cells have limited proliferative capacity, suggesting that the leukaemic clone may be maintained. by a rare population of stem cells(1-5). This putative leukaemic stem cell has not been characterized because the available in vitro assays can only detect progenitors with limited proliferative and replating potential(4-7). We have now identified an AML-initiating cell by transplantation into severe combined immune-deficient (SCID) mice. These cells homed to the bone marrow and proliferated extensively in response to in vivo cytokine treatment, resulting in a pattern of dissemination and leukaemic cell morphology similar to that seen in the original patients. Limiting dilution analysis showed that the frequency of these leukaemia-initiating cells in the peripheral blood of AML patients was one engraftment unit in 250,000 cells. We fractionated AML cells on the basis of cell-surface-marker expression and found that the leukaemia-initiating cells that could engraft SCID mice to produce large numbers of colony-forming progenitors were CD34(+) CD38(-); however, the CD34(+) CD38(+) and CD34(-) fractions contained no cells with these properties. This in vivo model replicates many aspects of human AML and defines a new leukaemia-initiating cell which is less mature than colony-forming cells.
C1 UNIV TORONTO, HOSP SICK CHILDREN, RES INST, DEPT GENET, TORONTO M5G 1X8, ON, CANADA.
   UNIV TORONTO, DEPT MOLEC & MED GENET, TORONTO M5G 1X8, ON, CANADA.
   CLIN RES INST MONTREAL, MONTREAL H2W 1R7, PQ, CANADA.
   PRINCESS MARGARET HOSP, DEPT MED, TORONTO M4X 1K9, ON, CANADA.
   PRINCESS MARGARET HOSP, DEPT ONCOL PATHOL, TORONTO M4X 1K9, ON, CANADA.
   ROSWELL PK CANC INST, DEPT MED, BUFFALO, NY 14263 USA.
C3 University of Toronto; Hospital for Sick Children (SickKids); University of Toronto; Institut de Recherche Clinique de Montreal (IRCM); Universite de Montreal; University of Toronto; University Health Network Toronto; Princess Margaret Cancer Centre; University of Toronto; University Health Network Toronto; Princess Margaret Cancer Centre; Roswell Park Comprehensive Cancer Center
NR 24
TC 3813
Z9 4722
U1 5
U2 278
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 645
EP 648
DI 10.1038/367645a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800054
PM 7509044
DA 2026-03-10
ER

PT J
AU LAZEBNIK, YA
   KAUFMANN, SH
   DESNOYERS, S
   POIRIER, GG
   EARNSHAW, WC
AF LAZEBNIK, YA
   KAUFMANN, SH
   DESNOYERS, S
   POIRIER, GG
   EARNSHAW, WC
TI CLEAVAGE OF POLY(ADP-RIBOSE) POLYMERASE BY A PROTEINASE WITH PROPERTIES LIKE ICE
SO NATURE
LA English
DT Article
ID death gene ced-3; enzyme; apoptosis; synthetase; induction; cdna
AB RECENT studies suggest that proteases of the interleukin 1-beta-converting enzyme (ICE)/ced-3 family are involved in initiating the active phase of apoptosis(1-3). Here we identify a novel protease resembling ICE (prICE) that is active in a cell-free system that reproduces the morphological and biochemical events of apoptosis(4). prICE cleaves the nuclear enzyme poly(ADP-ribose) polymerase (PARP) at a tetrapeptide sequence identical to one of two ICE sites in pro-interleukin-1-beta. However, prICE does not cleave purified pro-interleukin-1-beta, and purified ICE does not cleave PARP, indicating that the two activities are distinct. Inhibition of prICE abolishes all manifestations of apoptosis in the extracts including morphological changes, cleavage of PARP and production of an oligonucleosomal ladder. These studies suggest that prICE might be pivotal in initiating the active phase of apoptosis in vitro and in intact cells.
C1 JOHNS HOPKINS UNIV,SCH MED,DEPT ONCOL,BALTIMORE,MD 21205.
   JOHNS HOPKINS UNIV,SCH MED,DEPT PHARMACOL,BALTIMORE,MD 21205.
   CHU LAVAL,RES CTR,DEPT MOLEC ENDOCRINOL,POLY ADP RIBOSE METAB GRP,ST FOY G1V 4G2,PQ,CANADA.
   UNIV LAVAL,ST FOY G1V 4G2,PQ,CANADA.
C3 Johns Hopkins University; Johns Hopkins University; Laval University; Laval University Hospital; Laval University
RP LAZEBNIK, YA (corresponding author), JOHNS HOPKINS UNIV,SCH MED,DEPT CELL BIOL & ANAT,725 N WOLFE ST,BALTIMORE,MD 21205, USA.
NR 22
TC 2399
Z9 2622
U1 0
U2 49
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 346
EP 347
DI 10.1038/371346a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400056
PM 8090205
DA 2026-03-10
ER

PT J
AU MOHLER, KM
   SLEATH, PR
   FITZNER, JN
   CERRETTI, DP
   ALDERSON, M
   KERWAR, SS
   TORRANCE, DS
   OTTENEVANS, C
   GREENSTREET, T
   WEERAWARNA, K
   KRONHEIM, SR
   PETERSEN, M
   GERHART, M
   KOZLOSKY, CJ
   MARCH, CJ
   BLACK, RA
AF MOHLER, KM
   SLEATH, PR
   FITZNER, JN
   CERRETTI, DP
   ALDERSON, M
   KERWAR, SS
   TORRANCE, DS
   OTTENEVANS, C
   GREENSTREET, T
   WEERAWARNA, K
   KRONHEIM, SR
   PETERSEN, M
   GERHART, M
   KOZLOSKY, CJ
   MARCH, CJ
   BLACK, RA
TI PROTECTION AGAINST A LETHAL DOSE OF ENDOTOXIN BY AN INHIBITOR OF TUMOR-NECROSIS-FACTOR PROCESSING
SO NATURE
LA English
DT Article
ID molecular-cloning; emerging family; tnf; purification; ligand; lipopolysaccharide; interleukin-1-beta; cytokines; precursor; homology
AB TUMOUR necrosis factor (tumour necrosis factor-alpha/cachectin) plays a critical role in certain physiological defensive responses but causes severe damage to the host organism when produced in excess(1). There are two forms of tumour necrosis factor, a type II membrane protein of relative molecular mass 26,000 (26K) and a soluble, 17K form generated from the cell-bound protein by proteolytic cleavage(2,3). The two forms of tumour necrosis factor and lymphotoxin-alpha (tumour necrosis factor-beta/lymphotoxin), a related protein, have similar but apparently not identical biological activities(4-6). A therapeutic agent which inhibited the release of tumour necrosis factor, but did not reduce the cell-associated activity or the level of lymphotoxin-alpha, might preserve the benefits of these cytokines while preventing tumour necrosis factor-induced damage. Here we describe a potent inhibitor of tumour necrosis factor processing and report that it protects mice from a lethal dose of endotoxin.
C1 IMMUNEX RES & DEV CORP,SEATTLE,WA 98101.
   AMER CYANAMID CO,LEDERLE LABS,DIV MED RES,PEARL RIVER,NY 10965.
NR 24
TC 571
Z9 622
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 218
EP 220
DI 10.1038/370218a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100053
PM 8028669
DA 2026-03-10
ER

PT J
AU MICHAELS, AF
   BATES, NR
   BUESSELER, KO
   CARLSON, CA
   KNAP, AH
AF MICHAELS, AF
   BATES, NR
   BUESSELER, KO
   CARLSON, CA
   KNAP, AH
TI CARBON-CYCLE IMBALANCES IN THE SARGASSO SEA
SO NATURE
LA English
DT Article
ID sub-tropical gyre; north-atlantic; euphotic zone; time-series; upper ocean; deep ocean; flux; nitrogen; oxygen; bermuda
AB THE net exchange of carbon dioxide between the atmosphere and the ocean, and thus the nature of the oceanic carbon sink, is dominated by the seasonal dynamics of carbon cycling in the upper ocean. This cycle represents a balance between abiotic and biotic carbon transport into, and export out of, the ocean's upper layer. Here we report measurements of these processes made over five years in the Sargasso Sea off Bermuda, as part of the US Joint Global Ocean Flux Study (JGOFS). We find that the decrease in carbon stocks from the spring to the autumn in the upper 150 m of the ocean is three times larger than the measured sum of biotic and abiotic fluxes out of this layer, This discrepancy can be explained either by failure to account for horizontal advection of carbon or by inaccuracies in the fluxes of sinking particles as measured using sediment traps. Either the traps miss 80% of the sinking particles, or 70% of the carbon cycling is due to advection (or a combination of both processes is responsible). Sediment-trap measurements of the Th-234 flux during this period suggest that most of the discrepancy may be due to inaccuracies in the trap methods, which would require a very general reassessment of existing ideas about particle export and remineralization of carbon in the oceans. If, on the other hand, advection is the main source of the discrepancy, the traditional one-dimensional (vertical) modelling of the oceanic carbon cycle cannot give a full account of carbon dynamics.
C1 WOODS HOLE OCEANOG INST,WOODS HOLE,MA 02543.
   UNIV MARYLAND,HORN POINT ENVIRONM LAB,CAMBRIDGE,MD 21613.
C3 Woods Hole Oceanographic Institution
RP MICHAELS, AF (corresponding author), BERMUDA BIOL STN RES,FERRY REACH GE01,BERMUDA.
NR 37
TC 220
Z9 237
U1 0
U2 36
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 537
EP 540
DI 10.1038/372537a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200048
DA 2026-03-10
ER

PT J
AU GRAHAM, A
   FRANCISWEST, P
   BRICKELL, P
   LUMSDEN, A
AF GRAHAM, A
   FRANCISWEST, P
   BRICKELL, P
   LUMSDEN, A
TI THE SIGNALING MOLECULE BMP4 MEDIATES APOPTOSIS IN THE RHOMBENCEPHALIC NEURAL CREST
SO NATURE
LA English
DT Article
ID bone morphogenetic protein-4; ventralizing factor; hindbrain; cells
AB THE pattern of skeletal structures and muscles in the branchial region of the head is profoundly influenced by the neural crest whose cells arise at discrete segmental levels of the chick hindbrain: specifically, rhombomeres (r)1 + 2, r4 and r6, whereas r3 and r5 are crest-depleted(2). We have demonstrated that an interaction between even-numbered rhombomeres and r3/r5 effects this depletion of neural crest, resulting in the sculpting of discrete migratory streams of neural crest(3). This mechanism acts through increased expression of msx2 and the induction of apoptosis in dorsal cells of r3 and r5 (ref. 3) (Fig. 1A). Here we demonstrate that the signalling molecule Bmp4 is expressed in r3 and r5 and is dependent on the neighbouring rhombomeres. Addition of recombinant BMP4 protein to explant cultures of r3 or r5, which produce neural crest when isolated from their neighbouring rhombomeres, upregulates msx2 and reinstates apoptosis in the neural crest population.
C1 UCL, SCH MED, DEPT MOLEC PATHOL, MED MOLEC BIOL UNIT, LONDON W1P 6DB, ENGLAND.
C3 University of London; University College London; UCL Medical School
RP GRAHAM, A (corresponding author), UNITED MED & DENT SCH, GUYS HOSP, DIV ANAT & CELL BIOL, MRC, LONDON SE1 9RT, ENGLAND.
NR 12
TC 445
Z9 479
U1 0
U2 9
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 684
EP 686
DI 10.1038/372684a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700088
PM 7990961
DA 2026-03-10
ER

PT J
AU DAVIES, K
AF DAVIES, K
TI DAMAGE REPORT FOR BRCA1
SO NATURE
LA English
DT Article
AB Three groups have together uncovered more than 20 distinct mutations in families with hereditary breast and ovarian cancer, offering important clues about the function of BRCA1.
NR 11
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 574
EP 574
DI 10.1038/372574a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200059
DA 2026-03-10
ER

PT J
AU TIITINEN, H
   MAY, P
   REINIKAINEN, K
   NAATANEN, R
AF TIITINEN, H
   MAY, P
   REINIKAINEN, K
   NAATANEN, R
TI ATTENTIVE NOVELTY DETECTION IN HUMANS IS GOVERNED BY PRE-ATTENTIVE SENSORY MEMORY
SO NATURE
LA English
DT Article
ID event-related potentials; mismatch negativity; frequency discrimination; selective-attention; auditory-cortex
AB BEING able to detect unusual, possibly dangerous events in the environment is a fundamental ability that helps ensure the survival of biological organisms(1-3). Novelty detection requires a memory system that models (builds neural representations of) events in the environment, so that changes are detected because they violate the predictions of the model. The earliest physiologically measurable brain response to novel auditory stimuli is the mismatch negativity(4), MMN, a component of the event-related potential. It is elicited when a predictable series of unvarying stimuli is unexpectedly followed by a deviating stimulus(5). As the occurrence of MMN is not usually affected by the direction of attention(5-7), MMN reflects the operation of automatic sensory (echoic) memorys(8) the earliest memory system that builds traces of the acoustic environment against which new stimuli can be compared(5). The dependence of attentive novelty detection on earlier, pre-attentive processes, however, has remained elusive. Previous, related studies(9-12) seem to suggest a relationship between MMN and attentive processes, although no conclusive evidence has so far been shown. Here we address novelty detection in humans both on a physiological and behavioural level, and show how attentive novelty detection is governed by a pre-attentive sensory memory mechanism.
RP TIITINEN, H (corresponding author), UNIV HELSINKI,DEPT PSYCHOL,COGNIT PSYCHOPHYSIOL RES UNIT,SF-00014 HELSINKI,FINLAND.
NR 20
TC 556
Z9 604
U1 0
U2 33
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 90
EP 92
DI 10.1038/372090a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800078
PM 7969425
DA 2026-03-10
ER

PT J
AU YUN, MS
   HO, PTP
   LO, KY
AF YUN, MS
   HO, PTP
   LO, KY
TI A HIGH-RESOLUTION IMAGE OF ATOMIC-HYDROGEN IN THE M81 GROUP OF GALAXIES
SO NATURE
LA English
DT Article
ID neutral-hydrogen; kinematics; ngc-3077
AB It has long been recognized that interactions between galaxies are important in determining their evolution. The distribution of gas-out of which new stars are formed-is strongly affected; in particular, gas may be concentrated near the nucleus, leading to a burst of star formation(1-4). Here we present a map of atomic hydrogen (H I) in the nearest interacting group of galaxies (that dominated by M81), obtained by combining 12 separate fields observed with the Very Large Array. The Hr that surrounds M81, M82 and NGC3077 (the most prominent galaxies in the group) is dominated by filamentary structures, clearly demonstrating the violent disruption of this system by tidal interactions. These observations should have detected all H I complexes more massive than 10(6) solar masses, meaning that our map contains all structures that might evolve into new dwarf galaxies.
C1 CALTECH,PASADENA,CA 91125.
   UNIV ILLINOIS,DEPT ASTRON,URBANA,IL 61801.
C3 California Institute of Technology; University of Illinois System; University of Illinois Urbana-Champaign
RP YUN, MS (corresponding author), HARVARD SMITHSONIAN CTR ASTROPHYS,60 GARDEN ST,CAMBRIDGE,MA 02138, USA.
NR 30
TC 438
Z9 471
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 530
EP 532
DI 10.1038/372530a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200045
PM 7990925
DA 2026-03-10
ER

PT J
AU KULKARNI, SR
   FRAIL, DA
   KASSIM, NE
   MURAKAMI, T
   VASISHT, G
AF KULKARNI, SR
   FRAIL, DA
   KASSIM, NE
   MURAKAMI, T
   VASISHT, G
TI THE RADIO NEBULA OF THE SOFT GAMMA-RAY REPEATER 1806-20
SO NATURE
LA English
DT Article
ID high-energy transient; supernova-remnants; pulsars; stars
AB AN important clue to the nature of soft gamma-ray repeaters (SGRs), which emit recurrent bursts of gamma-rays, has been provided by the association of two of the three known SGRs with supernova remnants(1,2) (SNRs). Here we present radio images of the nonthermal radio nebula G10.0-0.3, a supernova remnant which has been associated previously(2) with SGR1806-20 (refs 3, 4). Our images show that the nebula is a plerion (that is, the radio emission is synchrotron radiation powered by a central pulsar), as revealed by the observation of a hierarchy of nested shells and a bright central peak. The recent detection(5) of an X-ray point source coincident with the radio peak and of a hard X-ray burst(5,6) from G10.0-0.3 confirms the SGR-SNR association. We propose that SGR1806-20 is an isolated pulsar that emits both steady and impulsive winds of relativistic particles, which together power the nebula. We suggest that the offset from the centres of the SNRs observed for both this object and SGR0526-66 (ref. 1), requiring high velocities of the pulsars, provides a clue to their formation mechanism.
C1 NATL RADIO ASTRON OBSERV,SOCORRO,NM 87801.
   USN,RES LAB,DIV REMOTE SENSING,WASHINGTON,DC 20375.
   INST SPACE & ASTRONAUT SCI,SAGAMIHARA,KANAGAWA 229,JAPAN.
C3 National Radio Astronomy Observatory (NRAO); United States Department of Defense; United States Navy; United States Naval Research Laboratory; NRL Chesapeake; Japan Aerospace Exploration Agency (JAXA); Institute of Space & Astronautical Science (ISAS)
RP KULKARNI, SR (corresponding author), CALTECH,DIV PHYS MATH & ASTRON 10524,PASADENA,CA 91125, USA.
NR 22
TC 102
Z9 103
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 129
EP 131
DI 10.1038/368129a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000059
DA 2026-03-10
ER

PT J
AU ACHARYA, KR
   PASSALACQUA, EF
   JONES, EY
   HARLOS, K
   STUART, DI
   BREHM, RD
   TRANTER, HS
AF ACHARYA, KR
   PASSALACQUA, EF
   JONES, EY
   HARLOS, K
   STUART, DI
   BREHM, RD
   TRANTER, HS
TI STRUCTURAL BASIS OF SUPERANTIGEN ACTION INFERRED FROM CRYSTAL-STRUCTURE OF TOXIC-SHOCK SYNDROME TOXIN-1
SO NATURE
LA English
DT Article
ID staphylococcal enterotoxin-b; receptor beta-chain; v-beta; t-cells; binding; identification; residues; stimulation; responses; molecules
AB SUPERANTIGENS stimulate T cells bearing particular T-cell receptor Vbeta sequences1,2, so they are extremely potent polyclonal T-cell mitogens. T-cell activation is preceded by binding of superantigens to class II major histocompatibility complex (MHC) molecules3. To further the structural characterization of these interactions, the crystal structure of a toxin associated with toxic-shock syndrome, TSST-1, which is a microbial superantigen, has been determined at 2.5 angstrom resolution. The N- and C-terminal domains of the structure both contain regions involved in MHC class II association; the C-terminal domain is also implicated in binding the T-cell receptor. Despite low sequence conservation, the TSST-1 topology is similar to the structure reported for the superantigen staphylococcal enterotoxin B4. But TSST-1 lacks several of the structural features highlighted as central to superantigen activity in the staphylococcal enterotoxin B and we therefore reappraise the structural basis of superantigen action.
C1 OXFORD CTR MOLEC SCI, OXFORD OX1 3QU, ENGLAND.
   LAB MOLEC BIOPHYS, OXFORD OX1 3QU, ENGLAND.
   PUBL HLTH LAB SERV, CTR APPL MICROBIOL & RES, DIV BIOL, SALISBURY SP4 0JG, ENGLAND.
C3 University of Oxford; University of Oxford
RP ACHARYA, KR (corresponding author), UNIV BATH, SCH BIOL & BIOCHEM, CLAVERTON DOWN, BATH BA2 7AY, AVON, ENGLAND.
NR 30
TC 148
Z9 167
U1 0
U2 5
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 94
EP 97
DI 10.1038/367094a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500068
PM 8107781
DA 2026-03-10
ER

PT J
AU DOLPH, PJ
   MANSONHING, H
   YARFITZ, S
   COLLEY, NJ
   DEER, JR
   SPENCER, M
   HURLEY, JB
   ZUKER, CS
AF DOLPH, PJ
   MANSONHING, H
   YARFITZ, S
   COLLEY, NJ
   DEER, JR
   SPENCER, M
   HURLEY, JB
   ZUKER, CS
TI AN EYE-SPECIFIC G-BETA SUBUNIT ESSENTIAL FOR TERMINATION OF THE PHOTOTRANSDUCTION CASCADE
SO NATURE
LA English
DT Article
ID protein-kinase-c; gamma-subunits; phospholipase-c; photoreceptor deactivation; drosophila photoreceptors; adenylyl cyclase; alpha-subunits; receptors; transduction; association
AB HETEROTRIMERIC G proteins couple various receptors to intracellular effector molecules. Although the role of the G alpha subunit in effector activation, guanine nucleotide exchange and GTP hydrolysis has been well studied(1-4), the cellular functions of the G beta subunits are less well understood(5,6). G beta gamma dimers bind G alpha subunits and anchor them to the membrane for presentation to the receptor(7,9). Tn specific systems, the G beta subunits have also been implicated in direct coupling to ion channels and to effector molecules(10-19). We have isolated Drosophila melanogaster mutants defective in an eye-specific G-protein beta-subunit (G beta e), and show here that the beta-subunit is essential for G-protein-receptor coupling in vivo. Remarkably, G beta mutants are also severely defective in the deactivation of the light response, demonstrating an essential role for the G beta subunit in terminating the active state of this signalling cascade.
C1 UNIV CALIF SAN DIEGO,DEPT BIOL,LA JOLLA,CA 92093.
   UNIV CALIF SAN DIEGO,DEPT NEUROSCI,LA JOLLA,CA 92093.
   UNIV CALIF SAN DIEGO,HOWARD HUGHES MED INST,LA JOLLA,CA 92093.
   UNIV WASHINGTON,DEPT BIOCHEM,SEATTLE,WA 98195.
C3 University of California System; University of California San Diego; University of California System; University of California San Diego; University of California System; University of California San Diego; Howard Hughes Medical Institute; University of Washington; University of Washington Seattle
FU NEI NIH HHS [R01 EY008768] Funding Source: Medline
NR 33
TC 55
Z9 66
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 59
EP 61
DI 10.1038/370059a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100058
PM 8015606
DA 2026-03-10
ER

PT J
AU BENJACOB, E
   SCHOCHET, O
   TENENBAUM, A
   COHEN, I
   CZIROK, A
   VICSEK, T
AF BENJACOB, E
   SCHOCHET, O
   TENENBAUM, A
   COHEN, I
   CZIROK, A
   VICSEK, T
TI GENERIC MODELING OF COOPERATIVE GROWTH-PATTERNS IN BACTERIAL COLONIES
SO NATURE
LA English
DT Article
ID fractal growth
AB BACTERIAL colonies must often cope with unfavourable environmental conditions(1,2). To do so, they have developed sophisticated modes of cooperative behaviour(3-10). It has been found that such behaviour can cause bacterial colonies to exhibit complex growth patterns similar to those observed during non-equilibrium growth processes in non-living systems(11) some of the qualitative features of the latter may be invoked to account for the complex patterns of bacterial growth(12-18). Here we show that a simple model of bacterial growth can reproduce the salient features of the observed growth patterns. The model incorporates random walkers, representing aggregates of bacteria, which move in response to gradients in nutrient concentration and communicate with each other by means of chemotactic 'feedback'. These simple features allow the colony to respond efficiently to adverse growth conditions, and generate self-organization over a wide range of length scales.
C1 EOTVOS LORAND UNIV, DEPT ATOM PHYS, H-1088 BUDAPEST, HUNGARY.
C3 Eotvos Lorand University
RP BENJACOB, E (corresponding author), TEL AVIV UNIV, RAYMOND & BEVERLY SACKLER FAC EXACT SCI, SCH PHYS & ASTRON, IL-69978 TEL AVIV, ISRAEL.
NR 22
TC 476
Z9 522
U1 0
U2 58
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 46
EP 49
DI 10.1038/368046a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900047
PM 8107881
DA 2026-03-10
ER

PT J
AU BRAGG, JR
   PRINCE, RC
   HARNER, EJ
   ATLAS, RM
AF BRAGG, JR
   PRINCE, RC
   HARNER, EJ
   ATLAS, RM
TI EFFECTIVENESS OF BIOREMEDIATION FOR THE EXXON-VALDEZ OIL-SPILL
SO NATURE
LA English
DT Article
ID petroleum
AB The effectiveness of bioremediation for oil spills has been difficult to establish on dynamic, heterogeneous marine shorelines. A new interpretative technique used following the 1989 Exxon Valdez spill in Alaska shows that fertilizer applications significantly increased rates of oil biodegradation. Biodegradation rates depended mainly on the concentration of nitrogen within the shoreline, the oil loading, and the extent to which natural biodegradation had already taken place. The results suggest ways to improve the effectiveness of bioremediation measures in the future.
C1 EXXON RES & ENGN CO,ANNANDALE,NJ 08801.
   W VIRGINIA UNIV,DEPT STAT & COMP SCI,MORGANTOWN,WV 26506.
   UNIV LOUISVILLE,DEPT BIOL,LOUISVILLE,KY 40292.
C3 Exxon Mobil Corporation; West Virginia University; University of Louisville
RP BRAGG, JR (corresponding author), EXXON PROD RES CO,POB 2189,HOUSTON,TX 77252, USA.
NR 31
TC 537
Z9 645
U1 1
U2 384
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 413
EP 418
DI 10.1038/368413a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000051
DA 2026-03-10
ER

PT J
AU FISHER, MJ
   RAO, IM
   AYARZA, MA
   LASCANO, CE
   SANZ, JI
   THOMAS, RJ
   VERA, RR
AF FISHER, MJ
   RAO, IM
   AYARZA, MA
   LASCANO, CE
   SANZ, JI
   THOMAS, RJ
   VERA, RR
TI CARBON STORAGE BY INTRODUCED DEEP-ROOTED GRASSES IN THE SOUTH-AMERICAN SAVANNAS
SO NATURE
LA English
DT Article
AB ESTIMATES of the global carbon dioxide balance have identified a substantial 'missing sink' of 0.4-4.3 Gt per year(1). It has been suggested that much of this may reside in the terrestrial biosphere(2). Here we present an analysis of the carbon stored by pastures based on deep-rooted grasses which have been introduced in the South American savannas. Although the deep-rooted grasses were chosen principally for agricultural reasons(3), we find that they also sequester significant amounts of organic carbon deep in the soil. If our study sites are representative of similar pastures throughout South America, this process could account for the sequestration of 100-507 Mt carbon per year-a substantial part of the 'missing sink'. Thus, although some land-use changes(4) (such as burning tropical rainforests) contribute to the atmospheric CO2 burden, we conclude that the introduced pastures studied here help to offset the effect of anthropogenic CO2 emissions.
RP FISHER, MJ (corresponding author), CTR INT AGR TROP, APARTADO AEREO 6713, CALI, COLOMBIA.
NR 25
TC 439
Z9 497
U1 2
U2 103
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 236
EP 238
DI 10.1038/371236a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000048
DA 2026-03-10
ER

PT J
AU ROUSSELET, J
   SALOME, L
   AJDARI, A
   PROST, J
AF ROUSSELET, J
   SALOME, L
   AJDARI, A
   PROST, J
TI DIRECTIONAL MOTION OF BROWNIAN PARTICLES INDUCED BY A PERIODIC ASYMMETRIC POTENTIAL
SO NATURE
LA English
DT Article
AB STRUCTURES possessing spatial asymmetry should act as pumps in the presence of dissipation alone(1-4), without the need for macroscopic forces or temperature differences(5) to drive vectorial motion. It has been shown theoretically(2-4,6,7) that particles subjected to an asymmetric periodic potential can display net directional motion even if the space-averaged forte is zero. Here we demonstrate such behaviour experimentally. We have studied the behaviour of colloidal particles suspended in solution and exposed to a sawtooth dielectric potential which is turned on and off periodically. The particles exhibit net motion with a velocity that depends on their size, suggesting applications in separation processes for objects in the size range 0.1-5 mu m-a range that includes biological structures such as viruses, cells and chromosomes(8). We furthermore point out the analogy between our device and motor protein assemblies.
C1 ECOLE SUPER PHYS & CHIM IND VILLE PARIS, PHYSICOCHIM THEOR GRP, CNRS, URA 1382, F-75231 PARIS 05, FRANCE.
C3 Universite PSL; Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI); Centre National de la Recherche Scientifique (CNRS)
RP ROUSSELET, J (corresponding author), CTR RECH PAUL PASCAL, AVE A SCHWEITZER, F-33600 PESSAC, FRANCE.
NR 12
TC 610
Z9 667
U1 0
U2 80
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 446
EP 448
DI 10.1038/370446a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700051
PM 8047163
DA 2026-03-10
ER

PT J
AU GOZIN, M
   AIZENBERG, M
   LIOU, SY
   WEISMAN, A
   BENDAVID, Y
   MILSTEIN, D
AF GOZIN, M
   AIZENBERG, M
   LIOU, SY
   WEISMAN, A
   BENDAVID, Y
   MILSTEIN, D
TI TRANSFER OF METHYLENE GROUPS PROMOTED BY METAL COMPLEXATION
SO NATURE
LA English
DT Article
ID carbon-carbon bond; activation; alkanes
AB SELECTIVE chemical transformations involving hydrocarbons are a major goal in synthetic chemistry. Transition-metal complexes are capable of promoting a range of selective transformations of organic molecules under mild conditions(1,2), and much effort has been devoted to studying their reactivity towards hydrocarbons(3-7). Here we report a reaction promoted by a rhodium complex in which a methylene (CH2) group can be abstracted from a methyl (CH3) group and inserted into a variety of bonds, such as Si-H, Si-Si and C-H. Our approach presently requires a certain coordination geometry in the metal complex, involving chelation of the metal centre, but we believe that it can be extended to other substrates capable of metal coordination and may eventually lead to a general strategy for CH2 transfer from hydrocarbons to other molecules under mild conditions.
C1 WEIZMANN INST SCI,DEPT ORGAN CHEM,IL-76100 REHOVOT,ISRAEL.
C3 Weizmann Institute of Science
NR 21
TC 109
Z9 116
U1 0
U2 34
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 42
EP 44
DI 10.1038/370042a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100051
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI DEAD ROMANOVS IDENTIFIED BY PCR
SO NATURE
LA English
DT Article
NR 4
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 580
EP 580
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300065
DA 2026-03-10
ER

PT J
AU GUI, JF
   LANE, WS
   FU, XD
AF GUI, JF
   LANE, WS
   FU, XD
TI A SERINE KINASE REGULATES INTRACELLULAR-LOCALIZATION OF SPLICING FACTORS IN THE CELL CYCLE
SO NATURE
LA English
DT Article
ID rich domains; sr proteins; phosphorylation; identification; nucleus; compartment; invitro; family; sites
AB Small nuclear ribonucleoprotein particles (snRNPs) and non-snRNP splicing factors containing a serine/arginine-rich domain (SR proteins) concentrate in 'speckles' in the nucleus of interphase cells(1). It is believed that nuclear speckles act as storage sites for splicing factors while splicing occurs on nascent transcripts(2). Splicing factors redistribute in response to transcription inhibition(3,4) or viral infection(5), and nuclear speckles break down and reform as cells progress through mitosis(6). We have now identified and cloned a kinase, SRPK1, which is regulated by the cell cycle and is specific for SR proteins; this kinase is related to a Caenorhabditis elegans kinase and to the fission yeast kinase Dsk1 (ref. 7). SRPK1 specifically induces the disassembly of nuclear speckles, and a high level of SRPK1 inhibits splicing in vitro. Our results indicate that SRPK1 mag have a central role in the regulatory network for splicing, controlling the intranuclear distribution of splicing factors in interphase cells, and the reorganization of nuclear speckles during mitosis.
C1 UNIV CALIF SAN DIEGO, DIV CELLULAR & MOLEC MED, LA JOLLA, CA 92093 USA.
   HARVARD UNIV, CAMBRIDGE, MA 02138 USA.
   CHINESE ACAD SCI, INST HYDROBIOL, WUHAN 430072, PEOPLES R CHINA.
C3 University of California System; University of California San Diego; Harvard University; Chinese Academy of Sciences; Institute of Hydrobiology, CAS
NR 30
TC 471
Z9 558
U1 1
U2 51
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 678
EP 682
DI 10.1038/369678a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900064
PM 8208298
DA 2026-03-10
ER

PT J
AU VONGERSDORFF, H
   MATTHEWS, G
AF VONGERSDORFF, H
   MATTHEWS, G
TI INHIBITION OF ENDOCYTOSIS BY ELEVATED INTERNAL CALCIUM IN A SYNAPTIC TERMINAL
SO NATURE
LA English
DT Article
ID frog neuromuscular-junction; vesicle fusion; transmitter release; chromaffin cells; exocytosis; secretion; membrane; endings; neurons; retina
AB DURING synaptic transmission in the nervous system, synaptic vesicles fuse with the plasma membrane of presynaptic terminals, releasing neurotransmitter by exocytosis(1,2). The vesicle membrane is then retrieved by endocytosis and recycled into new transmitter-containing vesicles. Exocytosis in synaptic terminals is calcium-dependent(7-9), and we now report that endocytosis also is regulated by the intracellular calcium concentration ([Ca2+](i)). Capacitance measurements(10,11) in synaptic terminals of retinal bipolar neurons revealed that endocytosis was strongly inhibited by elevated [Ca2+](i) in the range achieved by Ca2+-current activation. The rate of membrane retrieval was steeply dependent on [Ca2+](i), with a Hill coefficient of 4 and half-inhibition at similar to 500 nM. At [Ca2+](i) greater than or equal to 900 nM, endocytosis was entirely absent. The action of internal calcium on endocytosis represents a novel negative-feedback mechanism controlling the rate of membrane recovery in synaptic terminals after neurotransmitter secretion. As membrane retrieval is the first step in vesicle recycling, this mechanism may contribute to activity-dependent synaptic depression.
RP VONGERSDORFF, H (corresponding author), SUNY STONY BROOK, DEPT NEUROBIOL & BEHAV, STONY BROOK, NY 11794 USA.
NR 31
TC 233
Z9 241
U1 0
U2 9
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 652
EP 655
DI 10.1038/370652a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000051
PM 8065451
DA 2026-03-10
ER

PT J
AU MELNICK, J
   DUL, JL
   ARGON, Y
AF MELNICK, J
   DUL, JL
   ARGON, Y
TI SEQUENTIAL INTERACTION OF THE CHAPERONES BIP AND GRP94 WITH IMMUNOGLOBULIN-CHAINS IN THE ENDOPLASMIC-RETICULUM
SO NATURE
LA English
DT Article
ID glucose-regulated protein; binding-specificity; bip; hsp90; glycoprotein; cells; association; abundant; atpase; genes
AB During their transit through the endoplasmic reticulum, newly synthesized light and heavy chains of immunoglobulins associate with two endoplasmic reticulum stress proteins. BiP/GRP78, a member of the HSP70 family, binds these polypeptides, presumably through promiscuously exposed hydrophobic sequences(1,2), soon after their translocation into the endoplasmic reticulum(3,4). GRP94, another endoplasmic reticulum stress protein(5,6) homologous to HSP90(7-11), also associates,vith unassembled immunoglobulin chains(12), but its interaction is biochemically, kinetically and structurally distinct from BiP's. We report here that whereas BiP preferentially binds an early disulphide intermediate of light chain and dissociates within a few minutes, GRP94 exclusively binds fully oxidized molecules and dissociates with a half-time of 50 min. These results indicate that GRP94 is itself a chaperone which acts after BiP.
C1 DUKE UNIV,MED CTR,DEPT IMMUNOL,DURHAM,NC 27710.
C3 Duke University
NR 27
TC 369
Z9 422
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 373
EP 375
DI 10.1038/370373a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400056
PM 7913987
DA 2026-03-10
ER

PT J
AU SCHIFF, SJ
   JERGER, K
   DUONG, DH
   CHANG, T
   SPANO, ML
   DITTO, WL
AF SCHIFF, SJ
   JERGER, K
   DUONG, DH
   CHANG, T
   SPANO, ML
   DITTO, WL
TI CONTROLLING CHAOS IN THE BRAIN
SO NATURE
LA English
DT Article
ID rat hippocampal slice; interictal spiking; potassium; seizures; system
AB In a spontaneously bursting neuronal network in vitro, chaos can be demonstrated by the presence of unstable fixed-point behaviour. Chaos control techniques can increase the periodicity of such neuronal population bursting behaviour. Periodic pacing is also effective in entraining such systems, although in a qualitatively different fashion. Using a strategy of anticontrol such systems can be made less periodic. These techniques may be applicable to in vivo epileptic foci.
C1 GEORGE WASHINGTON UNIV, SCH MED, WASHINGTON, DC 20010 USA.
   USN, CTR SURFACE WARFARE, WHITE OAK LAB, SILVER SPRING, MD 20903 USA.
   GEORGIA INST TECHNOL, SCH PHYS, ATLANTA, GA 30332 USA.
C3 George Washington University; United States Department of Defense; United States Navy; University System of Georgia; Georgia Institute of Technology
RP SCHIFF, SJ (corresponding author), CHILDRENS NATL MED CTR, DEPT NEUROSURG, WASHINGTON, DC 20010 USA.
NR 23
TC 767
Z9 835
U1 0
U2 65
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 615
EP 620
DI 10.1038/370615a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000040
PM 8065447
DA 2026-03-10
ER

PT J
AU MEYER, A
   MORRISSEY, JM
   SCHARTL, M
AF MEYER, A
   MORRISSEY, JM
   SCHARTL, M
TI RECURRENT ORIGIN OF A SEXUALLY SELECTED TRAIT IN XIPHOPHORUS FISHES INFERRED FROM A MOLECULAR PHYLOGENY
SO NATURE
LA English
DT Article
ID mating preferences; female preferences; male swords; evolution
AB DARWIN1 believed that sexual selection accounts for the evolution of exaggerated male ornaments, such as the sword-like caudal fin extensions of male fishes of the genus Xiphophorus, that appear detrimental to survival. Swordtails continue to feature prominently in empirical work and theories of sexual selection; the pre-existing bias hypothesis has been offered as an explanation for the evolution of swords in these fishes2,3. Based upon a largely morphological phylogeny, this hypothesis suggests that female preference to mate with sworded males arose in ancestrally swordless species, thus pre-dating the origin of the sword itself and directly driving its evolution. Here we present a molecular phylogeny (based on mitochondrial and nuclear DNA sequences) of Xiphophorus which differs from the traditional one: it indicates that the sword originated and was lost repeatedly. Our phylogeny suggests that the ancestor of the genus is more likely to have possessed a sword than not, thus questioning the applicability of the pre-existing bias hypothesis as an explanation for the evolution of this sexually selected trait.
C1 SUNY STONY BROOK,PROGRAM GENET,STONY BROOK,NY 11794.
   UNIV WURZBURG,BIOZENTRUM,THEODOR BOVERI INST BIOWISSENSCH,D-97074 WURZBURG,GERMANY.
C3 State University of New York (SUNY) System; Stony Brook University; University of Wurzburg
RP MEYER, A (corresponding author), SUNY STONY BROOK,DEPT ECOL & EVOLUT,STONY BROOK,NY 11794, USA.
NR 43
TC 236
Z9 252
U1 0
U2 32
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 539
EP 542
DI 10.1038/368539a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500052
PM 8139686
DA 2026-03-10
ER

PT J
AU RAUMANN, BE
   ROULD, MA
   PABO, CO
   SAUER, RT
AF RAUMANN, BE
   ROULD, MA
   PABO, CO
   SAUER, RT
TI DNA RECOGNITION BY BETA-SHEETS IN THE ARC REPRESSOR-OPERATOR CRYSTAL-STRUCTURE
SO NATURE
LA English
DT Article
ID molecular-dynamics; binding; refinement
AB TRANSCRIPTION of the ant gene during lytic growth of bacteriophage P22 (ref. 1) is regulated by the cooperative binding of two Arc repressor dimers to a 21-base-pair operator site2,3. Here we report the co-crystal structure of this Arc tetramer-operator complex at 2.6 angstrom resolution. As expected from genetic4-6 and structural studies7 and from the co-crystal structure of the homologous Escherichia coli MetJ repressor8, each Arc dimer uses an antiparallel beta-sheet to recognize bases in the major groove. However, the Arc and MetJ complexes differ in several important ways: the beta-sheet-DNA interactions of Arc are far less symmetrical; DNA binding by Arc is accompanied by important conformational changes in the beta-sheet; and Arc uses a different part of its protein surface for dimer-dimer interactions.
C1 MIT,HOWARD HUGHES MED INST,CAMBRIDGE,MA 02139.
C3 Howard Hughes Medical Institute; Massachusetts Institute of Technology (MIT)
RP RAUMANN, BE (corresponding author), MIT,DEPT BIOL,CAMBRIDGE,MA 02139, USA.
NR 20
TC 271
Z9 295
U1 0
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 754
EP 757
DI 10.1038/367754a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100063
PM 8107872
DA 2026-03-10
ER

PT J
AU CANESSA, CM
   SCHILD, L
   BUELL, G
   THORENS, B
   GAUTSCHI, I
   HORISBERGER, JD
   ROSSIER, BC
AF CANESSA, CM
   SCHILD, L
   BUELL, G
   THORENS, B
   GAUTSCHI, I
   HORISBERGER, JD
   ROSSIER, BC
TI AMILORIDE-SENSITIVE EPITHELIAL NA+ CHANNEL IS MADE OF 3 HOMOLOGOUS SUBUNITS
SO NATURE
LA English
DT Article
ID ion channel; sodium-channel; hair cell; membrane; protein; stretch; chick; expression; currents; oocytes
AB THE amiloride-sensitive epithelial sodium channel constitutes the rate-limiting step for sodium reabsorption in epithelial cells that line the distal part of the renal tubule, the distal colon, the duct of several exocrine glands, and the lung. The activity of this channel is upregulated by vasopressin and aldosterone, hormones involved in the maintenance of sodium balance, blood volume and blood pressure1,2. We have identified the primary structure of the alpha-subunit of the rat epithelial sodium channel by expression cloning in Xenopus laevis oocytes3. An identical subunit has recently been reported4. Here we identify two other subunits (beta and gamma) by functional complementation of the alpha-subunit of the rat epithelial Na+ channel. The ion-selective permeability, the gating properties and the pharmacological profile of the channel formed by coexpressing the three subunits in oocytes are similar to that of the native channel.
C1 UNIV LAUSANNE,INST PHARMACOL & TOXIKOL,BUGNON 27,CH-1005 LAUSANNE,SWITZERLAND.
   GLAXO INST MOLEC BIOL,CH-1228 PLAN LES OUATES,SWITZERLAND.
C3 University of Lausanne; GlaxoSmithKline; GlaxoSmithKline Switzerland
NR 33
TC 1767
Z9 1914
U1 0
U2 58
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 463
EP 467
DI 10.1038/367463a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900055
PM 8107805
DA 2026-03-10
ER

PT J
AU LANGERMANN, S
   PALASZYNSKI, S
   SADZIENE, A
   STOVER, CK
   KOENIG, S
AF LANGERMANN, S
   PALASZYNSKI, S
   SADZIENE, A
   STOVER, CK
   KOENIG, S
TI SYSTEMIC AND MUCOSAL IMMUNITY INDUCED BY BCG VECTOR EXPRESSING OUTER-SURFACE PROTEIN-A OF BORRELIA-BURGDORFERI
SO NATURE
LA English
DT Article
ID antibody-secreting cells; oral immunization; cholera-toxin; ospa; mice; enumeration; vaccine
AB THE bacillus Calmette-Guerin (BCG) is a live attenuated strain of Mycobacterium bovis which offers potential advantages as a vector for mucosal delivery of antigens(1-3). Recombinant BCG elicits protective humoral immune responses to a variety of antigens(4). Furthermore, BCG binds specifically to microfold cells(5) present in the epithelium overlying lymphoid follicles throughout the mucosal immune system(6-8). Here we show that a single intranasal vaccination with recombinant BCG expressing the outersurface protein A antigen from B. burgdorferi(9) results in a prolonged (more than one year) protective systemic IgG response and a highly sustained secretory IgA response which is disseminated throughout the mucosal immune system. Furthermore, intranasal immunization induces marked, organized lymphocyte accumulation in the proximal nasopharyngeal lymphoid tissue as well as at distal mucosal sites; the appearance and persistence of lymphoid aggregates correlates with the secretory immune responses. Thus intranasal immunization with recombinant BCG is a powerful method for inducing long-lasting secretory and systemic immune responses.
C1 UNIV TEXAS, HLTH SCI CTR, DEPT MICROBIOL, SAN ANTONIO, TX 78284 USA.
C3 University of Texas System; University of Texas at San Antonio
RP LANGERMANN, S (corresponding author), MEDIMMUNE INC, GAITHERSBURG, MD 20878 USA.
NR 26
TC 147
Z9 164
U1 0
U2 3
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 552
EP 555
DI 10.1038/372552a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200053
PM 7990928
DA 2026-03-10
ER

PT J
AU VALERA, S
   HUSSY, N
   EVANS, RJ
   ADAMI, N
   NORTH, RA
   SURPRENANT, A
   BUELL, G
AF VALERA, S
   HUSSY, N
   EVANS, RJ
   ADAMI, N
   NORTH, RA
   SURPRENANT, A
   BUELL, G
TI NEW CLASS OF LIGAND-GATED ION-CHANNEL DEFINED BY P-2X RECEPTOR FOR EXTRACELLULAR ATP
SO NATURE
LA English
DT Article
ID programmed cell-death; functional expression; potassium channel; transmission
AB EXTRACELLULAR ATP exerts its effects through P-2 purinoceptors(1): these are ligand-gated ion channels (P-2X)(2,3) or G-protein-coupled receptors (P-2Y, P-2U)(4). ATP at P-2X receptors mediates synaptic transmission between neurons(5-7) and from neurons to smooth muscle(1), being responsible, for example, for sympathetic vasoconstriction in small arteries and arterioles(8,9) We have now cloned a complementary DNA encoding the P-2X receptor from rat vas deferens and expressed it in Xenopus oocytes and mammalian cells. ATP activates a cation-selective ion channel with relatively high calcium permeability. Structural predictions suggest that the protein (399 amino acids long) is mostly extracellular and contains only two transmembrane domains plus a pore-forming motif which resembles that of potassium channels. The P-2X receptor thus defines a new family of ligand-gated ion channels.
RP VALERA, S (corresponding author), GLAXO INST MOLEC BIOL SA,14 CHEMIN AUIX,PLAN OUATES,CH-1228 GENEVA,SWITZERLAND.
NR 30
TC 916
Z9 1007
U1 0
U2 21
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 516
EP 519
DI 10.1038/371516a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900056
PM 7523951
DA 2026-03-10
ER

PT J
AU MERMALL, V
   MCNALLY, JG
   MILLER, KG
AF MERMALL, V
   MCNALLY, JG
   MILLER, KG
TI TRANSPORT OF CYTOPLASMIC PARTICLES CATALYZED BY AN UNCONVENTIONAL MYOSIN IN LIVING DROSOPHILA EMBRYOS
SO NATURE
LA English
DT Article
ID actin-filaments; acanthamoeba; localization; vesicles; movement; gene
AB MYOSINS are actin-activated ATPases that are able to translocate along actin filaments using energy derived from ATP hydrolysis. Non-muscle cells contain conventional myosins, which are similar in sequence and structure to muscle myosin, and a number of unconventional myosins whose head sequences are similar but tail sequences are unrelated to conventional myosins(1). The myosin superfamily currently consists of nine classes(2); Duosophila 95F is an unconventional myosin(3) and the original member of class VI, which includes a homologue found in pig kidney(2). Some unconventional myosins have been suggested as mediators of some types of intracellular transport(4,5), but there is little direct evidence for this function (but see ref. 6). We have observed transport of cytoplasmic particles in live Drosophila embryos in three dimensions using computational optical sectioning microscopy. We present here evidence that this transport is actin-based, ATP-dependent and catalysed by one such unconventional myosin, the 95F myosin. This is, to our knowledge, the first direct observation of transport catalysed by an unconventional myosin in living cells.
C1 WASHINGTON UNIV, INST BIOMED COMP, ST LOUIS, MO 63130 USA.
C3 Washington University (WUSTL)
RP MERMALL, V (corresponding author), WASHINGTON UNIV, DEPT BIOL, CAMPUS BOX 1137, ST LOUIS, MO 63130 USA.
NR 21
TC 116
Z9 123
U1 0
U2 4
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 560
EP 562
DI 10.1038/369560a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400049
PM 8202156
DA 2026-03-10
ER

PT J
AU WEN, L
   ROBERTS, SJ
   VINEY, JL
   WONG, FS
   MALLICK, C
   FINDLY, RC
   PENG, QS
   CRAFT, JE
   OWEN, MJ
   HAYDAY, AC
AF WEN, L
   ROBERTS, SJ
   VINEY, JL
   WONG, FS
   MALLICK, C
   FINDLY, RC
   PENG, QS
   CRAFT, JE
   OWEN, MJ
   HAYDAY, AC
TI IMMUNOGLOBULIN-SYNTHESIS AND GENERALIZED AUTOIMMUNITY IN MICE CONGENITALLY DEFICIENT IN ALPHA-BETA(+)T CELLS
SO NATURE
LA English
DT Article
ID b-cell; dna antibody; alpha-beta; autoantibody; repertoire; receptor; igm; expression; infection; strains
AB Through cognate B-cell-T-cell interactions and provision of cytokines, CD4(+) T-cell antigen receptor (TCR) alpha beta(+) T cells regulate immunoglobulin isotype synthesis(1), Murine IgG1 and IgE secretion is therefore substantially T-cell-dependent, whereas IgM and IgG3 secretion is not(2,3). Here we report that in the absence of alpha beta T cells, B cells expand, differentiate and secrete copious amounts of antibodies of 'T-dependent' isotypes. Moreover, the antibodies are reactive towards self-antigens, as in patients with systemic lupus erythematosus, so autoantibodies of 'T-dependent' type can develop without the help of CD4(+) alpha beta T cells. This phenotype is not evident in mice or humans that ape congenitally deficient in specific alpha beta T-cell functions, but bears comparison with B-cell hyperactivity and autoimmunity in transplant rejection and in immunodeficiencies such as AIDS(4,5).
C1 YALE UNIV,IMMUNOBIOL SECT,NEW HAVEN,CT 06511.
   YALE UNIV,RHEUMATOL SECT,NEW HAVEN,CT 06511.
   IMPERIAL CANC RES FUND,LONDON WC2A 3PX,ENGLAND.
   PFIZER INC,DIV CENT RES,GROTON,CT 06340.
C3 Yale University; Yale University; Cancer Research UK; Pfizer; Pfizer USA
RP WEN, L (corresponding author), YALE UNIV,DEPT BIOL,219 PROSPECT ST,NEW HAVEN,CT 06511, USA.
NR 29
TC 160
Z9 169
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 654
EP 658
DI 10.1038/369654a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900057
PM 8208291
DA 2026-03-10
ER

PT J
AU DACEY, DM
   LEE, BB
AF DACEY, DM
   LEE, BB
TI THE BLUE-ON OPPONENT PATHWAY IN PRIMATE RETINA ORIGINATES FROM A DISTINCT BISTRATIFIED GANGLION-CELL TYPE
SO NATURE
LA English
DT Article
ID lateral geniculate-nucleus; macaque retina; bipolar cells; monkey retina; rhesus-monkey; color-vision; cone inputs; sensitivity; morphology; neurons
AB COLOUR vision in humans and Old World monkeys begins with the differential activation of three types of cone photoreceptor which are maximally sensitive to short (S), medium (M) and long (L) wavelengths. Signals from the three cone types are relayed to the retinal ganglion cells via cone-specific bipolar cell types1-4. Colour-coding ganglion cells fall into two major physiological classes: the red-green opponent cells, which receive antagonistic input from M- and L-sensitive cones, and the blue-yellow opponent cells, which receive input from S-sensitive cones, opposed by combined M- and L-cone input. The neural mechanisms producing colour opponency are not understood. It has been assumed that both kinds of opponent signals are transmitted to the lateral geniculate nucleus by one type of ganglion cell, the midget cell5,6. We now report that a distinct non-midget ganglion cell type, the small bistratified cell, corresponds to the physiological type that receives excitatory input from S cones, the 'blue-on' cell. Our results thus demonstrate an anatomically distinct pathway that conveys S-cone signals to the brain. The morphology of the blue-on cell also suggest a novel hypothesis for the retinal circuitry underlying the blue-yellow opponent response.
C1 MAX PLANCK INST BIOPHYS CHEM, D-37077 GOTTINGEN, GERMANY.
C3 Max Planck Society
RP DACEY, DM (corresponding author), UNIV WASHINGTON, DEPT BIOL STRUCT, SEATTLE, WA 98195 USA.
NR 28
TC 545
Z9 629
U1 0
U2 33
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 731
EP 735
DI 10.1038/367731a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100057
PM 8107868
DA 2026-03-10
ER

PT J
AU WANG, LF
   HU, JY
AF WANG, LF
   HU, JY
TI BLUE-SHIFTED OXYGEN LINES AND THE CLUMPY EJECTA OF SUPERNOVA 1993J
SO NATURE
LA English
DT Article
ID ib supernovae; sn-1987a; model; distance; helium; phase; scale
AB MASSIVE stars that explode at the end of their lives (type II supernovae) have been generally thought to do so rather isotropically, but there have been very few near enough to our Galaxy to study in reasonable detail. Supernova 1993J, in the nearby galaxy M81, is the second-closest supernova since the invention of the telescope, which enables us to study its early evolution. Here we report the detection of blue-shifted oxygen lines only four months after the optical discovery of the supernova. Unlike the case of SN1987A (refs 1, 2), we suggest that this blue shift is not the result of dust formation, but probably arises because the photosphere of the supernova developed a complex, irregular structure near maximum light. The clumpy ejecta allows photons from oxygen on the near (blue-shifted) side of the photosphere, which would not be visible if the ejecta were smooth and isotropic, to escape and be detected, while the photons on the far (red-shifted) side of the supernova are still absorbed. This situation arises because of mixing of regions of different element groups(3,4), and clearly shows the importance of instabilities during the supernova explosion.
RP WANG, LF (corresponding author), CHINESE ACAD SCI,BEIJING ASTRON OBSERV,BEIJING 100080,PEOPLES R CHINA.
NR 18
TC 34
Z9 36
U1 2
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 380
EP 382
DI 10.1038/369380a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400049
DA 2026-03-10
ER

PT J
AU XIE, X
   HARRISON, DH
   SCHLICHTLING, I
   SWEET, RM
   KALABOKIS, VN
   SZENTGYORGYI, AG
   COHEN, C
AF XIE, X
   HARRISON, DH
   SCHLICHTLING, I
   SWEET, RM
   KALABOKIS, VN
   SZENTGYORGYI, AG
   COHEN, C
TI STRUCTURE OF THE REGULATORY DOMAIN OF SCALLOP MYOSIN AT 2.8 ANGSTROM RESOLUTION
SO NATURE
LA English
DT Article
ID light-chains; calcium-binding; peptide complex; calmodulin; protein; dissociation; actin
AB The regulatory domain of scallop myosin is a three-chain protein complex that switches on this major in response to Ca2+ binding. This domain has been crystallized and the structure solved to 2.8 Angstrom resolution. Side-chain interactions link the two light chains in tandem to adjacent segments of the heavy chain bearing the IQ-sequence motif. The Ca2+-binding site is a novel EF-hand motif on the essential light chain and is stabilized by linkages involving the heavy chain and both light chains, accounting for the requirement of all three chains for Ca2+ binding and regulation in the intact myosin molecule.
C1 BRANDEIS UNIV,ROSENSTIEL BASIC MED SCI RES CTR,WALTHAM,MA 02254.
   MAX PLANCK INST MED RES,W-6900 HEIDELBERG,GERMANY.
   BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973.
   BRANDEIS UNIV,DEPT BIOL,WALTHAM,MA 02254.
C3 Brandeis University; Max Planck Society; United States Department of Energy (DOE); Brookhaven National Laboratory; Brandeis University
NR 37
TC 289
Z9 314
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 306
EP 312
DI 10.1038/368306a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500037
PM 8127365
DA 2026-03-10
ER

PT J
AU PALBERG, T
   STREICHER, K
AF PALBERG, T
   STREICHER, K
TI RESONANT STICK-SLIP MOTION IN A COLLOIDAL CRYSTAL
SO NATURE
LA English
DT Article
ID suspensions; shear; modulus
AB THE frictional properties of solid bodies can often be described in terms of stick-slip motion, in which one body slides against another, at constant driving force, in an alternating series of sticking and slipping events, Stick-slip motion between surfaces separated by a very thin fluid layer was recently observed on the molecular scale1.  At the other extreme, macroscopic bodies can exhibit a coupling between stick-slip motion and mechanical (such as acoustic) resonances.  The stick-slip motion of a bow on a violin string, for example, excites resonant vibration of the string2. Here we describe the observation of such resonant stick-slip behaviour on the microscopic scale. We have studied the flow behaviour of colloidal crystals in a rectangular tube. These crystals, comprising a dense suspension of sub-micrometre-sized polystyrene spheres, are known to exhibit shear-induced melting at high flow rates3-6. We find that, at lower flow velocity, stick-slip processes at the interface between the crystal and the cell wall can excite resonances in the crystal, detectable as periodic shifts of the Bragg angle in optical diffraction. We show that the resonances can be tuned by varying the density of the suspension, which is equivalent to altering the tension in a violin string.
RP PALBERG, T (corresponding author), UNIV KONSTANZ,DEPT PHYS,D-78434 CONSTANCE,GERMANY.
NR 15
TC 24
Z9 25
U1 1
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 51
EP 54
DI 10.1038/367051a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500054
DA 2026-03-10
ER

PT J
AU RIDDIHOUGH, G
AF RIDDIHOUGH, G
TI COMMUNICATION BY HELIX
SO NATURE
LA English
DT Article
AB Understanding the complex web of intracellular signalling pathways is brought a step closer by determinations of the structure of the SH3 domain/peptide ligand interface.
NR 5
TC 1
Z9 1
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 392
EP 392
DI 10.1038/370392a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400065
DA 2026-03-10
ER

PT J
AU COUVIDAT, YC
AF COUVIDAT, YC
TI SCIENCE PARKS AS A FORCE IN EMPLOYMENT - BORDEAUX-TECHNOPOLIS AND SUSTAINABLE DEVELOPMENT
SO NATURE
LA English
DT Article
RP COUVIDAT, YC (corresponding author), INT ASSOC SCI PK,CTR MONTESQUIEU,BORDEAUX TECHNOPOLIS,F-33650 MARTILLAC,FRANCE.
NR 0
TC 0
Z9 0
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 168
EP 169
DI 10.1038/368168a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000073
DA 2026-03-10
ER

PT J
AU HARADA, A
   OGUCHI, K
   OKABE, S
   KUNO, J
   TERADA, S
   OHSHIMA, T
   SATOYOSHITAKE, R
   TAKEI, Y
   NODA, T
   HIROKAWA, N
AF HARADA, A
   OGUCHI, K
   OKABE, S
   KUNO, J
   TERADA, S
   OHSHIMA, T
   SATOYOSHITAKE, R
   TAKEI, Y
   NODA, T
   HIROKAWA, N
TI ALTERED MICROTUBULE ORGANIZATION IN SMALL-CALIBER AXONS OF MICE LACKING TAU-PROTEIN
SO NATURE
LA English
DT Article
ID paired helical filaments; molecular-structure; nervous-system; antisense oligonucleotides; cerebellar neurons; targeted mutation; quick-freeze; gene; localization; mouse
AB THE tau gene encodes a protein (Tau) that is a major neuronal microtubule-associated protein localized mostly in axons(1-4). It has microtubule-binding and tubulin-polymerizing activity in vitro(3,4) and is thought to make short crossbridges between axonal microtuhules(5,6). Further, tau-transfected non-neuronal cells extend long axon-like processes in which microtubule bundles resembling those in axons are formed(6-8). In contrast, tau antisense oligonucleotides selectively suppress axonal elongation in cultured neurons(9,10). Thus tau is thought to be essential for neuronal cell morphogenesis, especially axonal elongation and maintenance. To test this hypothesis, we used gene targeting to produce mice lacking the tau gene. We show that the nervous system of tau-deficient mice appears to be normal immunohistologically. Furthermore, axonal elongation is not affected in cultured neurons. But in some small-calibre axons, microtubule stability is decreased and microtubule organization is significantly changed. We observed an increase in microtubule-associated protein 1A which may compensate for the functions of tau in large-calibre axons. Our results argue against the suggested role of tau in axonal elongation but confirm that it is crucial in the stabilization and organization of axonal microtubules in a certain type of axon.
C1 UNIV TOKYO,SCH MED,DEPT ANAT & CELL BIOL,BUNKYO KU,TOKYO 113,JAPAN.
   UNIV TOKYO,SCH PHARMACEUT SCI,DEPT NEUROPATHOL & NEUROSCI,BUNKYO KU,TOKYO 113,JAPAN.
   JAPANESE FDN CANC RES,INST CANC,DEPT CELL BIOL,TOSHIMA KU,TOKYO 170,JAPAN.
C3 University of Tokyo; University of Tokyo; Japanese Foundation for Cancer Research
NR 30
TC 636
Z9 768
U1 0
U2 41
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 488
EP 491
DI 10.1038/369488a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600058
PM 8202139
DA 2026-03-10
ER

PT J
AU TOGGAS, SM
   MASLIAH, E
   ROCKENSTEIN, EM
   RALL, GF
   ABRAHAM, CR
   MUCKE, L
AF TOGGAS, SM
   MASLIAH, E
   ROCKENSTEIN, EM
   RALL, GF
   ABRAHAM, CR
   MUCKE, L
TI CENTRAL-NERVOUS-SYSTEM DAMAGE PRODUCED BY EXPRESSION OF THE HIV-1 COAT PROTEIN GP120 IN TRANSGENIC MICE
SO NATURE
LA English
DT Article
ID human-immunodeficiency-virus; astrocyte-specific expression; neocortical damage; activation; cleavage; injury; rat
AB MANY people infected with human immunodeficiency virus type 1 (HIV-1) develop neurological complications that can culminate in dementia and paralysis1. The discrepancy between the severity of impairment and the paucity of detectable HIV-1 within neurons has led to an intense search for diffusible virus- and host-derived factors that might be neurotoxic (see ref. 2 for review). The HIV-1 envelope glycoprotein gp120 is an extracellular protein that is shed from infected cells3 and so has the potential to diffuse and interact with distant uninfected brain cells. Studies on cultured immature cells suggest that gp120 induces neurotoxicity (reviewed in refs 2, 4), and systemic injection of gp120 in neonatal rats5 and intracerebroventricular injection in adult rats results in deleterious effects on the brain6,7. To assess the pathogenic potential of gp120 in the intact brain, we have now produced gp120 in the brains of transgenic mice and found a spectrum of neuronal and glial changes resembling abnormalities in brains of HIV-1-infected humans. The severity of damage correlated positively with the brain level of gp120 expression. These results provide in vivo evidence that gp120 plays a key part in HIV-1-associated nervous system impairment. This model should facilitate the evaluation and development of therapeutic strategies aimed at HIV-brain interactions.
C1 Scripps Res Inst, DEPT NEUROPHARMACOL, DIV VIROL, 10666 N TORREY PINES RD, LA JOLLA, CA 92037 USA.
   UNIV CALIF SAN DIEGO, DEPT NEUROSCI, LA JOLLA, CA 92093 USA.
   UNIV CALIF SAN DIEGO, DEPT PATHOL, LA JOLLA, CA 92093 USA.
   BOSTON UNIV, SCH MED, DEPT MED, BOSTON, MA 02118 USA.
   BOSTON UNIV, SCH MED, DEPT BIOCHEM, BOSTON, MA 02118 USA.
C3 Scripps Research Institute; University of California System; University of California San Diego; University of California System; University of California San Diego; Boston University; Boston University
NR 31
TC 626
Z9 697
U1 0
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 188
EP 193
DI 10.1038/367188a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000066
PM 8114918
DA 2026-03-10
ER

PT J
AU HARRINGTON, J
   LEBEAU, RP
   BACKES, KA
   DOWLING, TE
AF HARRINGTON, J
   LEBEAU, RP
   BACKES, KA
   DOWLING, TE
TI DYNAMIC RESPONSE OF JUPITER'S ATMOSPHERE TO THE IMPACT OF COMET SHOEMAKER-LEVY 9
SO NATURE
LA English
DT Article
ID stability; vortices
AB DURING the period 18-24 July 1994, over 20 fragments of comet Shoemaker-Levy 9 will collide with Jupiter1-3. The thermal and condensation signatures of inertia-gravity waves emanating from the impact sites will, if detectable, provide valuable insight into the stratification of Jupiter's atmosphere. We report here simulations of the event using a global multi-layer model4 of Jupiter's atmosphere and a range of impact kinetic energies (10(27)-10(30) erg) that allows for the uncertainties in the sizes and densities of the comet fragments5-8. The resulting inertia-gravity waves give rise to temperature perturbations in the range 0.004-1.2 K. The signature of the larger impacts may be detectable by thermal infrared imaging, and even weak signals may be detectable if one allows for the fact that the waves propagate in coherent rings centred on each impact site. Our simulations also indicate that a small vortex should form in the atmosphere following each impact, but that these will be sheared apart by the zonal winds within a few weeks.
RP HARRINGTON, J (corresponding author), MIT, 77 MASSACHUSETTS AVE, CAMBRIDGE, MA 02139 USA.
NR 24
TC 25
Z9 30
U1 0
U2 3
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 525
EP 527
DI 10.1038/368525a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500046
DA 2026-03-10
ER

PT J
AU NICOLAOU, KC
   YANG, Z
   LIU, JJ
   UENO, H
   NANTERMET, PG
   GUY, RK
   CLAIBORNE, CF
   RENAUD, J
   COULADOUROS, EA
   PAULVANNAN, K
   SORENSEN, EJ
AF NICOLAOU, KC
   YANG, Z
   LIU, JJ
   UENO, H
   NANTERMET, PG
   GUY, RK
   CLAIBORNE, CF
   RENAUD, J
   COULADOUROS, EA
   PAULVANNAN, K
   SORENSEN, EJ
TI TOTAL SYNTHESIS OF TAXOL
SO NATURE
LA English
DT Article
ID system; agent
AB TAXOL(1-4), a substance originally isolated from the Pacific yew tree (Taxus brevifolia) more than two decades ago, has recently been approved for the clinical treatment of cancer patients. Hailed as having provided one of the most significant advances in cancer therapy(5), this molecule exerts its anticancer activity by inhibiting mitosis through enhancement of the polymerization of tubulin and consequent stabilization of microtubules(6). The scarcity of taxol and the ecological impact of harvesting it have prompted extensive searches for alternative sources including semisynthesis, cellular culture production and chemical synthesis(2,3). The latter has been attempted for almost two decades, but these attempts have been thwarted by the magnitude of the synthetic challenge. Here we report the total synthesis of taxol by a convergent strategy, which opens a chemical pathway for the production of both the natural product itself and a variety of designed taxoids.
C1 UNIV CALIF SAN DIEGO, DEPT CHEM, SAN DIEGO, CA 92093 USA.
C3 University of California System; University of California San Diego
RP NICOLAOU, KC (corresponding author), SCRIPPS RES INST, DEPT CHEM, 10666 N TORREY PINES RD, LA JOLLA, CA 92037 USA.
NR 16
TC 1051
Z9 1322
U1 27
U2 819
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 630
EP 634
DI 10.1038/367630a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800049
PM 7906395
DA 2026-03-10
ER

PT J
AU TILMAN, D
   DOWNING, JA
AF TILMAN, D
   DOWNING, JA
TI BIODIVERSITY AND STABILITY IN GRASSLANDS
SO NATURE
LA English
DT Article
ID diversity; complexity; community; ecosystems; ecology; drought
AB ONE of the ecological tenets justifying conservation of biodiversity is that diversity begets stability. Impacts of biodiversity on population dynamics and ecosystem functioning have long been debated1-7, however, with many theoretical explorations2-6,8-11 but few field studies12-15. Here we describe a long-term study of grasslands16,17 which shows that primary productivity in more diverse plant communities is more resistant to, and recovers more fully from, a major drought. The curvilinear relationship we observe suggests that each additional species lost from our grasslands had a progressively greater impact on drought resistance. Our results support the diversity-stability hypothesis5,6,18,19, but not the alternative hypothesis that most species are functionally redundant19-21. This study implies that the preservation of biodiversity is essential for the maintenance of stable productivity in ecosystems.
C1 UNIV MONTREAL, DEPT SCI BIOL, MONTREAL H3C 3J7, QUEBEC, CANADA.
C3 Universite de Montreal
RP TILMAN, D (corresponding author), UNIV MINNESOTA, DEPT ECOL EVOLUT & BEHAV, 1987 UPPER BUFORD CIRCLE, ST PAUL, MN 55108 USA.
NR 31
TC 1679
Z9 2258
U1 26
U2 1230
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 363
EP 365
DI 10.1038/367363a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000065
DA 2026-03-10
ER

PT J
AU WURM, J
AF WURM, J
TI AUSTRALIAN PHARMACEUTICAL-INDUSTRY OBSERVED
SO NATURE
LA English
DT Article
RP WURM, J (corresponding author), SACS CONSULTING GRP,525 COLLINS ST,MELBOURNE,VIC 3000,AUSTRALIA.
NR 4
TC 0
Z9 0
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 259
EP 260
DI 10.1038/369259a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700063
PM 8183348
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI ENSENADA, THE CINDERELLA OF THE PACIFIC
SO NATURE
LA English
DT Article
NR 1
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 798
EP 798
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700031
DA 2026-03-10
ER

PT J
AU DAVIS, AA
   TEMPLE, S
AF DAVIS, AA
   TEMPLE, S
TI A SELF-RENEWING MULTIPOTENTIAL STEM-CELL IN EMBRYONIC RAT CEREBRAL-CORTEX
SO NATURE
LA English
DT Article
ID central-nervous-system; neural crest; neurons; lineage; differentiation; generation; astrocytes; progenitor; retina; oligodendrocytes
AB NEUROECTODERM cells in the cortical ventricular zone generate many diverse cell types, maintain the ventricular zone during embryonic life and create another germinal layer, the subventricular zone, which persists into adulthood(1,2). In other vertebrate tissues, including skin, intestine, blood and neural crest, stem cells are important in maintaining a germinal population and generating differentiated progeny(3-6). By following the fates of single ventricular zone cells in culture, we show here that self-renewing, multipotential stem cells are present in the embryonic rat cerebral cortex. Forty per cent of these stem cells produced all three principal cell types of the central nervous system: neurons, astrocytes and oligodendrocytes. Stem cells constituted about 7% of cortical clones; in contrast, over 80% consisted of small numbers of neurons or glia. We suggest that multipotential stem cells may be the ancestors of other cortical progenitor cells that exhibit more limited proliferation and more restricted repertoires of progeny fates.
C1 ALBANY MED COLL,DIV NEUROSURG,ALBANY,NY 12208.
C3 Albany Medical College
RP DAVIS, AA (corresponding author), ALBANY MED COLL,DEPT PHARMACOL,ALBANY,NY 12208, USA.
NR 29
TC 491
Z9 608
U1 1
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 263
EP 266
DI 10.1038/372263a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900050
PM 7969470
DA 2026-03-10
ER

PT J
AU TRAUTMAN, JK
   MACKLIN, JJ
   BRUS, LE
   BETZIG, E
AF TRAUTMAN, JK
   MACKLIN, JJ
   BRUS, LE
   BETZIG, E
TI NEAR-FIELD SPECTROSCOPY OF SINGLE MOLECULES AT ROOM-TEMPERATURE
SO NATURE
LA English
DT Article
ID optical microscopy; crystal; force
AB THE ability to observe the optical spectrum of a single molecule can afford insights into the interactions that distinguish one molecular environment from another. Such sensitivity has recently been achieved at liquid-helium temperatures(1-5). Here we show that the near-field scanning optical microscope(6,7) can be used to obtain the time-dependent emission spectrum of a single molecule in air at room temperature, with a spatial resolution of about 100 nm. We have examined single molecules of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine (diI) dispersed on polymethylmethacrylate. The spectra of individual molecules exhibit shifts of +/-8 nm relative to the average spectrum, and are typically narrower, as is expected for spectral lines broadened inhomogeneously (that is, by a distribution of molecular environments). The spectra also vary in width by up to 8 nm, some being as broad as the far-field many-molecule spectrum. The emission spectra of some individual molecules exhibit time-dependent shifts of up to 10 nm. This variety in spectral position, width, shape and time dependence can be understood within a model of inhomogeneous broadening in which there is a distribution of barrier heights to rearrangement of the molecular environment.
RP TRAUTMAN, JK (corresponding author), AT&T BELL LABS,600 MT AVE,MURRAY HILL,NJ 07974, USA.
NR 14
TC 393
Z9 438
U1 1
U2 84
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 40
EP 42
DI 10.1038/369040a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000045
DA 2026-03-10
ER

PT J
AU DAVIES, K
AF DAVIES, K
TI COMPLEX MACHINATIONS
SO NATURE
LA English
DT Article
AB New strategies for automated genotyping and linkage analysis will bring greater power to the study of complex hereditary disorders.
NR 6
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 158
EP 158
DI 10.1038/370158a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400063
DA 2026-03-10
ER

PT J
AU HAJNOCZKY, G
   THOMAS, AP
AF HAJNOCZKY, G
   THOMAS, AP
TI THE INOSITOL TRISPHOSPHATE CALCIUM-CHANNEL IS INACTIVATED BY INOSITOL TRISPHOSPHATE
SO NATURE
LA English
DT Article
ID permeabilized hepatocytes; ca2+ mobilization; release; 1,4,5-trisphosphate; stores; cells
AB ACTIVATION Of intracellular Ca2+ channels by inositol 1,4,5-trisphosphate (Ins(1,4,5)P-3) represents the initial Ca2+ mobilization step in response to many extracellular signals(1). Here we report that Ins(1,4,5)P-3-induced channel activation in permeabilized hepatocytes is followed by a time-dependent inactivation, which is a direct consequence of ligand binding. The inactivation by Ins(1,4,5)P-3 parallels the quantal character of channel opening, giving rise to a unique process of incremental inactivation whereby discrete channel populations are inhibited at each Ins(1,4,5)P-3 dose. Ins(1,4,5)P-3 can induce inactivation in the absence of stored Ca2+, but the inactivation rate is enhanced by increases of cytosolic Ca2+. The inhibitory effect of Ins(1,4,5)P-3 can be reversed by Ins(1,4,5)P-3 washout, or by chelation of cytosolic Ca2+. Thus, Ins(1,4,5)P-3 and Ca2+ act as coinhibitors of the Ins(1,4,5)P-3-sensitive Ca2+ channel. Inactivation is an inherent consequence of Ins(1,4,5)P-3-induced channel opening which can terminate increases of cytosolic Ca2+.
C1 THOMAS JEFFERSON UNIV, DEPT PATHOL & CELL BIOL, PHILADELPHIA, PA 19107 USA.
C3 Thomas Jefferson University
NR 16
TC 157
Z9 164
U1 0
U2 1
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 474
EP 477
DI 10.1038/370474a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700060
PM 8047168
DA 2026-03-10
ER

PT J
AU BREWER, JP
AF BREWER, JP
TI SCIENCE PARKS AS A FORCE IN EMPLOYMENT - RESEARCH-TRIANGLE PARK
SO NATURE
LA English
DT Article
RP BREWER, JP (corresponding author), RES TRIANGLE FDN,COMMUN,2 HANES DR,POB 12255,RES TRIANGLE PK,NC 27709, USA.
NR 0
TC 0
Z9 0
U1 1
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 169
EP 170
DI 10.1038/368169a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000074
DA 2026-03-10
ER

PT J
AU LAPTHORN, AJ
   HARRIS, DC
   LITTLEJOHN, A
   LUSTBADER, JW
   CANFIELD, RE
   MACHIN, KJ
   MORGAN, FJ
   ISAACS, NW
AF LAPTHORN, AJ
   HARRIS, DC
   LITTLEJOHN, A
   LUSTBADER, JW
   CANFIELD, RE
   MACHIN, KJ
   MORGAN, FJ
   ISAACS, NW
TI CRYSTAL-STRUCTURE OF HUMAN CHORIONIC-GONADOTROPIN
SO NATURE
LA English
DT Article
ID human choriogonadotropin-beta; site-directed mutagenesis; human luteinizing-hormone; receptor-binding; glycoprotein hormones; disulfide bonds; terminal region; alpha-subunit; immunological property; biological property
AB The three-dimensional structure of human chorionic gonadotropin shows that each of its two different subunits has a similar topology, with three disulphide bonds forming a cystine knot. This same folding motif Is found in some protein growth factors. The heterodimer is stabilized by a segment of the beta-subunit which wraps around the alpha-subunit and is covalently linked like a seat belt by the disulphide Cys 26-Cys 110. This extraordinary feature appears to be essential not only for the association of these heterodimers but also for receptor binding by the glycoprotein hormones.
C1 UNIV GLASGOW,DEPT CHEM,GLASGOW G12 8QQ,SCOTLAND.
   COLUMBIA UNIV,DEPT MED,NEW YORK,NY 10032.
   ST VINCENTS INST MED RES,MELBOURNE,VIC 3065,AUSTRALIA.
   LATROBE UNIV,DEPT BIOCHEM,MELBOURNE,VIC 3083,AUSTRALIA.
C3 University of Glasgow; Columbia University; St. Vincent's Institute of Medical Research; La Trobe University
NR 51
TC 816
Z9 907
U1 0
U2 39
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 455
EP 461
DI 10.1038/369455a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600047
PM 8202136
DA 2026-03-10
ER

PT J
AU KOCISKO, DA
   COME, JH
   PRIOLA, SA
   CHESEBRO, B
   RAYMOND, GJ
   LANSBURY, PT
   CAUGHEY, B
AF KOCISKO, DA
   COME, JH
   PRIOLA, SA
   CHESEBRO, B
   RAYMOND, GJ
   LANSBURY, PT
   CAUGHEY, B
TI CELL-FREE FORMATION OF PROTEASE-RESISTANT PRION PROTEIN
SO NATURE
LA English
DT Article
ID scrapie-associated form; cultured-cells; prp; conversion; diseases; fibrils; biology; acid
AB THE infectious agent (or 'prion') of the transmissible spongiform encephalopathies (TSEs) such as scrapie resembles a virus in that it replicates in vivo and has distinct strains(1), but it was postulated long ago to contain only protein(2-3). More recently, PrPSc, a pathogenic, scrapie-associated form of the host-encoded prion protein (PrP), was identified as a possible primary TSE agent protein(4-6). PrPSc is defined biochemically by its insolubility and resistance to proteases(7) and is derived post-translationally from normal, protease-sensitive PrP (PrPc)(8,9). The conversion seems to involve conformational change rather than covalent modification(10-13) However, the conversion mechanism and the relationship of PrPSc formation to TSE agent replication remain unclear. Here we report the conversion of PrPc to protease-resistant forms similar to PrPSc in a cell-free system composed of substantially purified constituents. This conversion was selective and required the presence of preexisting PrPSc, providing direct evidence that PrPSc derives from specific PrPc-PrPSc interactions.
C1 MIT,DEPT CHEM,CAMBRIDGE,MA 02139.
   NIAID,ROCKY MT LABS,PERSISTENT VIRAL DIS LAB,HAMILTON,MT 59840.
C3 Massachusetts Institute of Technology (MIT); National Institutes of Health (NIH) - USA; NIH National Institute of Allergy & Infectious Diseases (NIAID)
NR 30
TC 791
Z9 895
U1 1
U2 41
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 471
EP 474
DI 10.1038/370471a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700059
PM 7913989
DA 2026-03-10
ER

PT J
AU PONMAN, TJ
   ALLAN, DJ
   JONES, LR
   MERRIFIELD, M
   MCHARDY, IM
   LEHTO, HJ
   LUPPINO, GA
AF PONMAN, TJ
   ALLAN, DJ
   JONES, LR
   MERRIFIELD, M
   MCHARDY, IM
   LEHTO, HJ
   LUPPINO, GA
TI A POSSIBLE FOSSIL GALAXY GROUP
SO NATURE
LA English
DT Article
ID brightest cluster members; ccd surface photometry; x-ray-property; elliptical galaxy; abell clusters; compact-groups; cooling flows; gas; sample; radio
AB MOST galaxies, including our own, are located in groups(1). In the most compact galaxy groups, the members are separated on the sky by only a few galactic radii, and numerical simulations(2) suggest that such systems will merge to form a single elliptical galaxy (a 'fossil group') in a few billion years. Recent observations(3,4) have shown that some compact groups are surrounded by X-ray-emitting haloes of hot gas, and have suggested that they contain substantial amounts of dark matter. An elliptical galaxy formed by the merger of such a group will retain its halo(4), which is unaffected by merging. Using recent X-ray observations from Rosat we have searched for fossil groups, and we report here the discovery of a possible candidate at a redshift of 0.171. This candidate has a high X-rays luminosity, comparable to those of the brighter compact groups(5) and appears similar to the giant elliptical galaxies at the centres of clusters, yet it is apparently isolated. Its optical properties are also consistent with an origin as the merged remains of a typical compact group.
C1 UNIV SOUTHAMPTON,DEPT PHYS,SOUTHAMPTON SO9 5NH,HANTS,ENGLAND.
   TURKU UNIV OBSERV,TUORLA OBSERV,SF-21500 PIIKKIO,FINLAND.
   UNIV HAWAII,INST ASTRON,HONOLULU,HI 96822.
C3 University of Southampton; University of Turku; University of Hawaii System
RP PONMAN, TJ (corresponding author), UNIV BIRMINGHAM,SCH PHYS & SPACE RES,BIRMINGHAM B15 2TT,ENGLAND.
NR 28
TC 251
Z9 264
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 462
EP 464
DI 10.1038/369462a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600048
DA 2026-03-10
ER

PT J
AU NEPSTAD, DC
   DECARVALHO, CR
   DAVIDSON, EA
   JIPP, PH
   LEFEBVRE, PA
   NEGREIROS, GH
   DASILVA, ED
   STONE, TA
   TRUMBORE, SE
   VIEIRA, S
AF NEPSTAD, DC
   DECARVALHO, CR
   DAVIDSON, EA
   JIPP, PH
   LEFEBVRE, PA
   NEGREIROS, GH
   DASILVA, ED
   STONE, TA
   TRUMBORE, SE
   VIEIRA, S
TI THE ROLE OF DEEP ROOTS IN THE HYDROLOGICAL AND CARBON CYCLES OF AMAZONIAN FORESTS AND PASTURES
SO NATURE
LA English
DT Article
ID soil-water content; tropical deforestation; climate change; dynamics; basin
AB DEFORESTATIONS and logging transform more forest in eastern and southern Amazonia than in any other region of the world(1-3). This forest alteration affects regional hydrology(4-11) and the global carbon cycle(12-14), but current analyses of these effects neglect an important deep-soil link between the water and carbon cycles. Using rainfall data, satellite imagery and field studies, we estimate here that half of the closed forests of Brazilian Amazonia depend on deep root systems to maintain green canopies during the dry season. Evergreen forests in northeastern Para state maintain evapotranspiration during five-month dry periods by absorbing water from the soil to depths of more than 8 m. In contrast, although the degraded pastures of this region also contain deep-rooted woody plants, most pasture plants substantially reduce their leaf canopy in response to seasonal drought, thus reducing dry-season evapotranspiration and increasing potential subsurface runoff relative to the forests they replace. Deep roots that extract water also provide carbon to the soil. The forest soil below Im depth contains more carbon than does above-ground biomass, and as much as 15% of this deep-soil carbon turns over on annual or decadal timescales. Thus, forest alteration that affects depth distributions of carbon inputs from roots mag also affect net carbon storage in the soil.
C1 EMBRAPA, CPATU, BR-66001 BELEM, PARA, BRAZIL.
   UNIV CALIF IRVINE, DEPT EARTH SYST SCI, IRVINE, CA 92717 USA.
C3 Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA); University of California System; University of California Irvine
RP NEPSTAD, DC (corresponding author), WOODS HOLE RES CTR, WOODS HOLE, MA 02543 USA.
NR 32
TC 1108
Z9 1251
U1 3
U2 371
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 666
EP 669
DI 10.1038/372666a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700083
DA 2026-03-10
ER

PT J
AU CLARK, EA
   LEDBETTER, JA
AF CLARK, EA
   LEDBETTER, JA
TI HOW B-CELLS AND T-CELLS TALK TO EACH OTHER
SO NATURE
LA English
DT Article
ID dependent antibody-responses; activation antigen-b7; lymphocytes-t; soluble form; receptor; cd40; ligand; expression; adhesion; signal
AB The B cells of the immune system, which secrete antibodies against foreign antigens, are fully specific and effective only after maturation in lymph nodes and other lymphoid tissues. Immunocompetent T cells play a crucial part in this process, but the molecular details of the way in which the two cell types interact have only recently become apparent.
C1 UNIV WASHINGTON,REG PRIMATE RES CTR,SEATTLE,WA 98195.
   BRISTOL MYERS SQUIBB CO,PHARMACEUT RES INST,SEATTLE,WA 98121.
C3 University of Washington; University of Washington Seattle; Bristol-Myers Squibb
RP CLARK, EA (corresponding author), UNIV WASHINGTON,MED CTR,DEPT MICROBIOL,SC-42,SEATTLE,WA 98195, USA.
NR 60
TC 620
Z9 666
U1 1
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 425
EP 428
DI 10.1038/367425a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900044
PM 8107800
DA 2026-03-10
ER

PT J
AU ACKERMAN, AS
   TOON, OB
   HOBBS, PV
AF ACKERMAN, AS
   TOON, OB
   HOBBS, PV
TI REASSESSING THE DEPENDENCE OF CLOUD CONDENSATION NUCLEUS CONCENTRATION ON FORMATION RATE
SO NATURE
LA English
DT Article
ID boundary-layer; model; stratocumulus
AB MARINE stratocumulus clouds play an important role in the Earth's radiation budget. The albedo of these clouds depends on-the cloud droplet size distribution, and therefore, in part, on the number density of cloud condensation nuclei (CCN)1. It has been postulated2 that a positive feedback loop between increased CCN concentrations and decreased drizzle gives rise to a bistable system, in which there are two equilibrium CCN concentration regimes. According to this model, CCN concentration is only weakly dependent on the CCN production rate within the stable regimes, but very strongly dependent on this rate in the transition region between the regimes. If correct, this strong dependence implies that a small increase in the production of CCN over the oceans could drastically increase the planetary albedo. Using a more sophisticated model3 than that used previously, we find no evidence for bistability. However, we find that CCN concentrations are generally strongly dependent on their production rate, so that changes in the latter would influence the Earth's albedo. We also find that the timescale for reducing high CCN concentrations can be as long as several days, which implies that high CCN concentrations can persist in clouds advected to regions of lower CCN production rate.
C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035.
C3 National Aeronautics & Space Administration (NASA); NASA Ames Research Center
RP ACKERMAN, AS (corresponding author), UNIV WASHINGTON,DEPT ATMOSPHER SCI,SEATTLE,WA 98195, USA.
NR 10
TC 21
Z9 22
U1 2
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 445
EP 447
DI 10.1038/367445a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900049
DA 2026-03-10
ER

PT J
AU LU, Z
   MACKINNON, R
AF LU, Z
   MACKINNON, R
TI ELECTROSTATIC TUNING OF MG2+ AFFINITY IN AN INWARD-RECTIFIER K+ CHANNEL
SO NATURE
LA English
DT Article
ID guinea-pig heart; potassium channel; functional expression; ventricular cells; magnesium block; internal mg-2+; rectification; activation; ions
AB INWARD-RECTIFIER potassium channels conduct K+ across the cell membrane more efficiently in the inward than outward direction. This unusual conduction property is directly related to the biological action of these channels(1-6). One basis for inward rectification is voltage-dependent blockade by intracellular Mg2+ (refs 1, 7-9): strong inward-rectifier channels are so sensitive to intracellular Mg2+ that no outward K+ current is measurable under physiological conditions; weak inward rectifiers are less sensitive and allow some K+ to flow outwards. Background K1 channels and acetylcholine-regulated K+ channels from the heart are examples of strong inward rectifiers and ATP-sensitive K+ channels are weak rectifiers(1,7-10). Here we show that mutations at one position in the second transmembrane segment can alter the Mg2+ affinity and convert a weakly rectifying channel (ROMK1) into a strong rectifier. The amino acid at this position exposes its side chain to the aqueous pore and affects Mg2+ blockade as well as K+ conduction through an electrostatic mechanism.
RP LU, Z (corresponding author), HARVARD UNIV,SCH MED,DEPT NEUROBIOL,220 LONGWOOD AVE,BOSTON,MA 02115, USA.
NR 29
TC 289
Z9 319
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 243
EP 246
DI 10.1038/371243a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000051
PM 7915826
DA 2026-03-10
ER

PT J
AU MENG, J
   WYSS, AR
   DAWSON, MR
   ZHAI, RJ
AF MENG, J
   WYSS, AR
   DAWSON, MR
   ZHAI, RJ
TI PRIMITIVE FOSSIL RODENT FROM INNER-MONGOLIA AND ITS IMPLICATIONS FOR MAMMALIAN PHYLOGENY
SO NATURE
LA English
DT Article
ID guinea-pig
AB THE evolutionary origin of rodents is obscured by the group's sudden and highly transformed first appearance in the fossil record(1,2) in the latest Paleocene. We report here the discovery of nearly complete dental remains of an extraordinary new primitive rodent from strata of transitional Paleocene-Eocene age in Inner Mongolia, China. The strikingly conservative morphological features of this taxon, Tribosphenomys minutus, gen. et sp. nov., substantially modify previous ideas about the ancestral rodent morphotype, which in turn has important implications for understanding the origin of rodents and their relationship to other eutherian mammals. This new fossil, in conjunction with recent morphological(3) and molecular(4,5) evidence confirming rodent monophyly, indicates the need for a reassessment of phylogenetic affinities among gliriform eutherians. Our results indicate a sister-group position of the new taxon to other rodents, and support the alliance of lagomorphs (rabbits) and rodents (cohort Glires). They also suggest the paraphyly of an extinct assemblage, the 'Eurymylidae', and reveal an unexpectedly complex pattern of character evolution near the ancestry of Rodentia.
C1 INST VERTEBRATE PALEONTOL & PALEOANTHROPOL, BEIJING, PEOPLES R CHINA.
   UNIV CALIF SANTA BARBARA, DEPT GEOL SCI, SANTA BARBARA, CA 93106 USA.
   CARNEGIE MUSEUM NAT HIST, VERTEBRATE PALEONTOL SECT, PITTSBURGH, PA 15213 USA.
C3 Chinese Academy of Sciences; Institute of Vertebrate Paleontology & Paleoanthropology, CAS; University of California System; University of California Santa Barbara
RP MENG, J (corresponding author), AMER MUSEUM NAT HIST, DEPT VERTEBRATE PALEONTOL, CENT PK W & 79TH ST, NEW YORK, NY 10024 USA.
NR 30
TC 72
Z9 81
U1 1
U2 15
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 134
EP 136
DI 10.1038/370134a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400054
PM 8022481
DA 2026-03-10
ER

PT J
AU KOBZIK, L
   REID, MB
   BREDT, DS
   STAMLER, JS
AF KOBZIK, L
   REID, MB
   BREDT, DS
   STAMLER, JS
TI NITRIC-OXIDE IN SKELETAL-MUSCLE
SO NATURE
LA English
DT Article
ID reactive oxygen; sarcoplasmic-reticulum; synthase; localization; sulfhydryls; mechanism; oxidation; proteins; release; forms
AB REACTIVE oxygen intermediates modulate skeletal muscle contraction(1,2), but little is known about the role of nitric oxide (NO). Here we show that rat skeletal muscle expresses neuronal-type NO synthase and that activity varies among several respiratory and limb muscles. Immunohistochemistry showed prominent staining of type II (fast) fibre cell membranes with antibodies against neuronal-type NO synthase. NO synthase activity in muscles correlated with type II fibre density. Resting diaphragm muscle produced detectable NOx, but no reactive oxygen intermediates. In contrast, actively contracting muscle generated increased levels of reactive oxygen intermediates. Contractile function was augmented by blockers of NO synthase, extracellular NO chelation, and guanylyl cyclase inhibition; it was depressed by NO donors and by increased levels of cyclic GMP. Force-frequency plots of different muscles showed an inverse correlation between NO synthase activity and force development. Our results support two physiological functions of NO in skeletal muscle. The first is to promote relaxation through the cGMP pathway(3,4). The second is to modulate increases In contraction that are dependent on reactive oxygen intermediates and which are thought to occur through reactions with regulatory thiols on the sarcoplasmic reticulum(5,6).
C1 DUKE UNIV,MED CTR,DEPT MED,DIV PULM,DURHAM,NC 27710.
   DUKE UNIV,MED CTR,DEPT CELL BIOL,DURHAM,NC 27710.
   DUKE UNIV,MED CTR,DIV CARDIOVASC,DURHAM,NC 27710.
   BRIGHAM & WOMENS HOSP,DEPT PATHOL,BOSTON,MA 02115.
   HARVARD UNIV,SCH PUBL HLTH,BOSTON,MA 02115.
   BAYLOR COLL MED,HOUSTON,TX 77030.
   UNIV CALIF SAN FRANCISCO,DEPT PHYSIOL,SAN FRANCISCO,CA 94143.
C3 Duke University; Duke University; Duke University; Harvard University; Harvard University Medical Affiliates; Brigham & Women's Hospital; Harvard University; Harvard T.H. Chan School of Public Health; Baylor College of Medicine; University of California System; University of California San Francisco
NR 28
TC 864
Z9 935
U1 0
U2 23
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 546
EP 548
DI 10.1038/372546a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200051
PM 7527495
DA 2026-03-10
ER

PT J
AU GROSSHANS, J
   BERGMANN, A
   HAFFTER, P
   NUSSLEINVOLHARD, C
AF GROSSHANS, J
   BERGMANN, A
   HAFFTER, P
   NUSSLEINVOLHARD, C
TI ACTIVATION OF THE KINASE PELLE BY TUBE IN THE DORSOVENTRAL SIGNAL-TRANSDUCTION PATHWAY OF DROSOPHILA EMBRYO
SO NATURE
LA English
DT Article
ID dorsal-ventral polarity; toll gene-product; nuclear-localization; proto-oncogene; establishment; pattern; cactus; morphogen; gradient; receptor
AB THE concentration of Dorsal protein in the nucleus determines cell fate along the dorsoventral axis of the Drosophila embryo(1-13). The dorsal-group genes and the cactus gene are required for production and transmission of a localized signal an the ventral side of the embryo(4,5) which determines the position of the highest nuclear concentration of Dorsal protein(1-3) The ventralizing signal produced in somatic cells(6) is transmitted through the perivitelline space(7) to the integral membrane protein Toll(8). Inside the embryo it leads to dissociation of the cytoplasmic Dorsal-Cactus complex and subsequent nuclear localization of Dorsal protein(9,10). Two components are known to mediate the signal transduction between Toll and Dorsal-Cactus(11,12): Pelle, a serine/threonine protein kinase(13), and Tube, a protein with an unknown biochemical activity(14). Here we construct gain-of-function alleles of pelle and tube and show that pelle functions downstream of tube. In addition, Pelle and Tube interact directly with one another. We propose that Tube is a direct activator of the protein kinase Pelle.
RP GROSSHANS, J (corresponding author), MAX PLANCK INST ENTWICKLUNGSBIOL,GENET ABT 3,SPEMANNSTR 35,D-72076 TUBINGEN,GERMANY.
NR 30
TC 110
Z9 131
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 563
EP 566
DI 10.1038/372563a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200056
PM 7527496
DA 2026-03-10
ER

PT J
AU MCMINN, A
   HEIJNIS, H
   HODGSON, D
AF MCMINN, A
   HEIJNIS, H
   HODGSON, D
TI MINIMAL EFFECTS OF UVB-RADIATION ON ANTARCTIC DIATOMS OVER THE PAST 20 YEARS
SO NATURE
LA English
DT Article
ID sea ice; phytoplankton
AB IT HAS been suggested(1-3) that increased springtime WB radiation caused by stratospheric ozone depletion is likely to reduce primary production and induce changes in the species composition of Antarctic marine phytoplankton. Experiments conducted at Arthur Harbour in the Antarctic Peninsula revealed a reduction in primary productivity at both ambient and increased levels of UVB (ref. 4). Laboratory studies have shown that most species in culture are sensitive to high UVB levels, although the level at which either growth or photosynthesis is inhibited is variable(5,6). Stratospheric ozone depletion, with resultant increased springtime UVB irradiance, has been occurring with increasing severity since the late 1970s. Thus the phytoplankton community has already experienced about 20 years' exposure to increasing levels of UVB radiation. Here we present analyses of diatom assemblages from high-resolution stratigraphic sequences from anoxic basins in fjords of the Vestfold Hills, Antarctica. We find that compositional changes in the diatom component of the phytoplankton community over the past 20 years cannot be distinguished from long-term natural variability, although there is some indication of a decline in the production of some sea-ice diatoms. We anticipate that our results are applicable to other Antarctic coastal regions, where thick ice cover and the timing of the phytoplankton bloom protect the phytoplankton from the effects of increased UVB radiation.
C1 UNIV TASMANIA,INST ANTARCTIC & SO OCEAN STUDIES,HOBART,TAS 7001,AUSTRALIA.
   AUSTRALIAN NUCL SCI & TECHNOL ORG,ENVIRONM RADIOCHEM LAB,MENAI,NSW 2234,AUSTRALIA.
   UNIV TASMANIA,DEPT PLANT SCI,HOBART,TAS 7001,AUSTRALIA.
C3 University of Tasmania; Australian Nuclear Science & Technology Organisation; University of Tasmania
RP MCMINN, A (corresponding author), UNIV TASMANIA,ANTARTIC CRC,BOX 252C,HOBART,TAS 7001,AUSTRALIA.
NR 18
TC 33
Z9 33
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 547
EP 549
DI 10.1038/370547a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700051
DA 2026-03-10
ER

PT J
AU GAVAGHAN, H
AF GAVAGHAN, H
TI GENETICS BUSINESS BOOMING YET UNCERTAIN
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 1
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 341
EP 342
DI 10.1038/369341a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900059
PM 8183375
DA 2026-03-10
ER

PT J
AU MERTENS, F
   IMBIHL, R
AF MERTENS, F
   IMBIHL, R
TI SQUARE CHEMICAL WAVES IN THE CATALYTIC REACTION NO+H-2 ON A RHODIUM(110) SURFACE
SO NATURE
LA English
DT Article
ID oscillatory behavior; microscope; reduction; rh(110); h-2; no; rh
AB IT WAS realized as early as 1906(1) that coupling between an autocatalytic reaction and the diffusion of the autocatalytic component can give rise to a propagating reaction front-a chemical wave. Chemical waves have been studied intensively in fluid-phase reaction-diffusion systems(2), but in recent years a variety of spatiotemporal patterns has also been observed for oscillatory reactions on single-crystal surfaces(3,4). One important new aspect that has been introduced by these studies is that of anisotropic diffusion, as a consequence of the fixed surface geometry on which the diffusion of the adsorbed particles takes place. Here we report the observation of a transition from elliptical to square-shaped concentric chemical waves in the reaction of NO and H-2 On a rhodium(110) surface. The elliptical pattern is characteristic of simple anisotropic diffusion, but we attribute the origin of the square pattern to a state-dependent anisotropy-that is an anisotropy that varies along the wave profile as changes in the adsorbate coverage generate different reconstructions of the substrate structure. This interplay between diffusional anisotropy and the state of the system can be expected to be quite general and to give rise to new varieties of oscillatory patterning.
RP MERTENS, F (corresponding author), MAX PLANCK GESELL,FRITZ HABER INST,FARADAYWEG 4-6,D-14195 BERLIN,GERMANY.
NR 13
TC 80
Z9 83
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 124
EP 126
DI 10.1038/370124a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400050
DA 2026-03-10
ER

PT J
AU SULLENGER, BA
   CECH, TR
AF SULLENGER, BA
   CECH, TR
TI RIBOZYME-MEDIATED REPAIR OF DEFECTIVE MESSENGER-RNA BY TARGETED TRANSSPLICING
SO NATURE
LA English
DT Article
ID rna enzyme; tetrahymena ribozyme; escherichia-coli; sequence; cleavage; expression; binding; invivo; model; virus
AB RIBOZYMES can be targeted to cleave specific RNAs(1-8), which has led to much interest in their potential as gene inhibitors(3,9,10). Such trans-cleaving ribozymes join a growing list of agents that stop the flow of genetic information(11,12). Here we describe a different application of ribozymes for which they may be uniquely suited. By targeted trans-splicing, a ribozyme can replace a defective portion of RNA with a functional sequence. The self-splicing intron from Tetrahymena thermophila(13) was previously shown to mediate trans-splicing of oligonucleotides in vitro(14,15). As a model system for messenger RNA repair, this group I intron was re-engineered to regenerate the proper coding capacity of short, truncated lacZ transcripts. Trans-splicing was efficient in vitro and proceeded in Escherichia coli to generate translatable lacZ messages. Targeted trans-splicing represents a general means of altering the sequence of specified transcripts and may provide a new approach to the treatment of many genetic diseases.
C1 UNIV COLORADO,HOWARD HUGHES MED INST,DEPT CHEM & BIOCHEM,BOULDER,CO 80309.
C3 Howard Hughes Medical Institute; University of Colorado System; University of Colorado Boulder
NR 30
TC 211
Z9 269
U1 1
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 619
EP 622
DI 10.1038/371619a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900056
PM 7935797
DA 2026-03-10
ER

PT J
AU ERNFORS, P
   LEE, KF
   JAENISCH, R
AF ERNFORS, P
   LEE, KF
   JAENISCH, R
TI MICE LACKING BRAIN-DERIVED NEUROTROPHIC FACTOR DEVELOP WITH SENSORY DEFICITS
SO NATURE
LA English
DT Article
ID factor prevents; cell-death; neurons; survival; motoneurons; invivo
AB DURING vertebrate development, neuronal survival depends on target-derived neurotrophic factors(1,2). Brain-derived neurotrophic factor(3) (BDNF), a member of the neurotrophin family, can prevent the death of particular peripheral sensory neurons in vitro(4-6), and of central motor neurons as well as dopaminergic and cholinergic neurons of the basal forebrain during development(7-9). It also prevents the death of motor neurons and midbrain dopaminergic neurons induced by lesions(8,10-12). Here we show that mutant mice lacking BDNF have severe deficiencies in coordination and balance, associated with excessive degeneration in several sensory ganglia including the vestibular ganglion. The few remaining vestibular axons fail to contact the vestibular sensory epithelia, and terminate in the adjacent connective tissue. Survival of sympathetic, midbrain dopaminergic and motor neurons is not affected. These results indicate that BDNF is required for the survival and target innervation of particular neuronal populations.
C1 MIT,DEPT BIOL,CAMBRIDGE,MA 02142.
C3 Massachusetts Institute of Technology (MIT)
RP ERNFORS, P (corresponding author), MIT,WHITEHEAD INST BIOMED RES,9 CAMBRIDGE CTR,CAMBRIDGE,MA 02142, USA.
NR 23
TC 857
Z9 975
U1 1
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 147
EP 150
DI 10.1038/368147a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000066
PM 8139657
DA 2026-03-10
ER

PT J
AU KIMBEL, WH
   JOHANSON, DC
   RAK, Y
AF KIMBEL, WH
   JOHANSON, DC
   RAK, Y
TI THE 1ST SKULL AND OTHER NEW DISCOVERIES OF AUSTRALOPITHECUS-AFARENSIS AT HADAR, ETHIOPIA
SO NATURE
LA English
DT Article
ID functional-morphology; cranial morphology; hominids; position
AB THE Hadar Formation in Ethiopia is a prolific source of Pliocene Hominidae attributed to the species Australopithecus afarensis1. Since 1990, three seasons of field work have contributed 53 new specimens to the hominid inventory from Hadar, including the first fairly complete adult skull. Ranging from 3.0 to 3.4 million years in age (Fig. 1)2-4 , the new specimens bear on key debates in hominid palaeontology, including the taxonomic implications of sample variation and the reconstruction of locomotor behaviour. They confirm the taxonomic unity of A. afarensis and constitute the largest body of evidence for about 0.9 million years of stasis in the earliest known hominid species.
C1 TEL AVIV UNIV, SACKLER SCH MED, DEPT ANAT, TEL AVIV, ISRAEL.
C3 Tel Aviv University; Sackler Faculty of Medicine
RP KIMBEL, WH (corresponding author), INST HUMAN ORIGINS, 2453 RIDGE RD, BERKELEY, CA 94709 USA.
NR 31
TC 159
Z9 180
U1 0
U2 19
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 449
EP 451
DI 10.1038/368449a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000061
PM 8133889
DA 2026-03-10
ER

PT J
AU KUHLBRANDT, W
   WANG, DN
   FUJIYOSHI, Y
AF KUHLBRANDT, W
   WANG, DN
   FUJIYOSHI, Y
TI ATOMIC MODEL OF PLANT LIGHT-HARVESTING COMPLEX BY ELECTRON CRYSTALLOGRAPHY
SO NATURE
LA English
DT Article
ID photosynthetic reaction center; a/b-protein complex; chlorophyll-a; rhodopseudomonas-viridis; energy-transfer; 3a resolution; density maps; membrane; microscopy; phosphorylation
AB The structure of the light-harvesting chlorophyll a/b-protein complex, an integral membrane protein, has been determined at 3.4 Angstrom resolution by electron crystallography of two-dimensional crystals. Two of the three membrane-spanning alpha-helices are held together by ion pairs formed by charged residues that also serve as chlorophyll ligands. In the centre of the complex, chlorophyll a is in close contact with chlorophyll b for rapid energy transfer, and with two carotenoids that prevent the formation of toxic singlet oxygen.
C1 PROT ENGN RES INST,SUITA,OSAKA 565,JAPAN.
RP KUHLBRANDT, W (corresponding author), EUROPEAN MOLEC BIOL LAB,MEYERHOFSTR 1,D-69117 HEIDELBERG,GERMANY.
NR 53
TC 1578
Z9 1723
U1 2
U2 219
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 614
EP 621
DI 10.1038/367614a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800044
PM 8107845
DA 2026-03-10
ER

PT J
AU WAGA, S
   STILLMAN, B
AF WAGA, S
   STILLMAN, B
TI ANATOMY OF A DNA-REPLICATION FORK REVEALED BY RECONSTITUTION OF SV40 DNA-REPLICATION IN-VITRO
SO NATURE
LA English
DT Article
ID simian virus-40 dna; polymerase-alpha-primase; lagging strand synthesis; cell nuclear antigen; t-antigen; saccharomyces-cerevisiae; factor-c; invitro replication; accessory proteins; initiation
AB Complete enzymatic replication of DNA from the simian virus 40 origin has been reconstituted with T antigen and highly purified cellular proteins. DNA polymerase-alpha/primase functions primarily to synthesize RNA-DNA primers for initiation of DNA replication at the origin and for priming each Okazaki fragment. A polymerase switching mechanism requiring replication factor C and the proliferating cell nuclear antigen allows two molecules of DNA polymerase-delta to replicate both strands of the double helix conjointly.
RP WAGA, S (corresponding author), COLD SPRING HARBOR LAB,POB 100,COLD SPRING HARBOR,NY 11724, USA.
NR 50
TC 519
Z9 580
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 207
EP 212
DI 10.1038/369207a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700048
PM 7910375
DA 2026-03-10
ER

PT J
AU RIDDIHOUGH, G
AF RIDDIHOUGH, G
TI ONE IN THE EYE
SO NATURE
LA English
DT Article
ID crystallins
AB A double insight into visual accommodation by the eye lens in birds and into the activity of a superfamily of metabolic enzymes is provided by the structure of turkey lens delta-crystallin.
NR 4
TC 2
Z9 2
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 538
EP 538
DI 10.1038/371538a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900063
PM 7935769
DA 2026-03-10
ER

PT J
AU BICKLE, MJ
AF BICKLE, MJ
TI THE ROLE OF METAMORPHIC DECARBONATION REACTIONS IN RETURNING STRONTIUM TO THE SILICATE SEDIMENT MASS
SO NATURE
LA English
DT Article
ID trace-element geochemistry; sr-isotopic provenance; rb-sr; regional metamorphism; continental-crust; carbon-dioxide; sm-nd; evolution; seawater; orogeny
AB The strontium-isotope evolution of the Earth's silicate sediments indicates that they must interact with a strontium reservoir whose Sr-87/Sr-86 ratio is relatively low. The Sr-isotope budget for these sediments can be balanced if the Sr lost to solution by weathering is replaced by Sr from the oceans (through diagenesis) and from carbonate sediments (through metamorphic decarbonation reactions). Because of the latter connection, the Sr-87/Sr-86 ratio of silicate sediments can constrain the contribution of metamorphism to the Earth-atmosphere CO2 flux.
RP BICKLE, MJ (corresponding author), UNIV CAMBRIDGE,DEPT EARTH SCI,DOWNING ST,CAMBRIDGE CB2 3EQ,ENGLAND.
NR 65
TC 20
Z9 25
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 699
EP 704
DI 10.1038/367699a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100047
DA 2026-03-10
ER

PT J
AU SPOOR, F
   WOOD, B
   ZONNEVELD, F
AF SPOOR, F
   WOOD, B
   ZONNEVELD, F
TI IMPLICATIONS OF EARLY HOMINID LABYRINTHINE MORPHOLOGY FOR EVOLUTION OF HUMAN BIPEDAL LOCOMOTION
SO NATURE
LA English
DT Article
ID semicircular canals; endolymph flow; afarensis; neurons; model; east
AB The upright posture and obligatory bipedalism of modern humans are unique among living primates, The evolutionary history of this behaviour has traditionally been pursued by functional analysis of the postcranial skeleton and the preserved footprint trails of fossil hominids. Here H e report a systematic attempt to reconstruct the locomotor behaviour of early hominids by looking at a major component of the mechanism for the unconscious perception of movement, namely by examining the vestibular system of living primates and early hominids. High-resolution computed tomography was used to generate cross-sectional images of the bony labyrinth. Among the fossil hominids the earliest species to demonstrate the modern human morphology is Home erectus. In contrast, the semicircular canal dimensions in crania from southern Africa attributed to Australopithecus and Paranthropus resemble those of the extant great apes. Among early Home specimens, the canal dimensions of Stw 53 are unlike those seen in any of the hominids or great apes, whereas those of SK 847 are modern-human-like.
C1 UNIV LIVERPOOL,DEPT HUMAN ANAT & CELL BIOL,HOMINID PALAEONTOL RES GRP,LIVERPOOL L69 3BX,ENGLAND.
   UNIV UTRECHT HOSP,DEPT RADIOL,UTRECHT,NETHERLANDS.
C3 University of Liverpool; Utrecht University; Utrecht University Medical Center
NR 37
TC 226
Z9 273
U1 0
U2 93
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 645
EP 648
DI 10.1038/369645a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900054
PM 8208290
DA 2026-03-10
ER

PT J
AU MORGAN, ME
   KINGSTON, JD
   MARINO, BD
AF MORGAN, ME
   KINGSTON, JD
   MARINO, BD
TI CARBON ISOTOPIC EVIDENCE FOR THE EMERGENCE OF C4 PLANTS IN THE NEOGENE FROM PAKISTAN AND KENYA
SO NATURE
LA English
DT Article
ID faunal change; east-africa; miocene; diet; bone; photosynthesis; evolution; collagen; enamel; c-13
AB DETAILED palaeorecords of terrestrial environments are critical for interpretations of the late Miocene mammalian evolution. Here we assess the development of modern tropical grassland (C4) biomes, an important ecosystem for modern faunas. We present enamel apatite C-13/C-12 isotope ratios of fauna from two sequences, the Siwaliks from the Potwar Plateau in northern Pakistan, and the Tugen Hills Succession in Kenya (Fig. 1). Our data do not support previous suggestions of a restricted global date for C4 emergence associated with decreased atmospheric CO2 around 7 Myr ago1. Instead, C4 grasses are first recorded as a dietary component in Pakistan at 9.4 Myr and increase as a foraging resource over the next few million years. In Kenya, C4 grasses are present by 15.3 Myr but are not the primary dietary resource of herbivores until 7 Myr. A wide range of C3 and C4 dietary signals characterizes the latest Miocene/Pliocene of Kenya.
C1 HARVARD UNIV,DEPT EARTH & PLANETARY SCI,CAMBRIDGE,MA 02138.
   YALE UNIV,DEPT ANTHROPOL,NEW HAVEN,CT 06520.
C3 Harvard University; Yale University
RP MORGAN, ME (corresponding author), HARVARD UNIV,DEPT ANTHROPOL,CAMBRIDGE,MA 02138, USA.
NR 33
TC 242
Z9 296
U1 0
U2 28
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 162
EP 165
DI 10.1038/367162a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000057
DA 2026-03-10
ER

PT J
AU KLEIN, R
   SILOSSANTIAGO, I
   SMEYNE, RJ
   LIRA, SA
   BRAMBILLA, R
   BRYANT, S
   ZHANG, L
   SNIDER, WD
   BARBACID, M
AF KLEIN, R
   SILOSSANTIAGO, I
   SMEYNE, RJ
   LIRA, SA
   BRAMBILLA, R
   BRYANT, S
   ZHANG, L
   SNIDER, WD
   BARBACID, M
TI DISRUPTION OF THE NEURATROPHIN-3 RECEPTOR GENE TRKC ELIMINATES LA MUSCLE AFFERENTS AND RESULTS IN ABNORMAL MOVEMENTS
SO NATURE
LA English
DT Article
ID motor neurons; stem-cells; rna
AB THE trkC gene(1,2) is expressed throughout the mammalian nervous system(3-5) and encodes a series of tyrosine protein kinase isoforms that serve as receptors for neurotrophin-3 (NT3), a member of the nerve growth factor (NGF) family of neurotrophic factors(2,6-8). One of these isoforms, gp145(trkC)/TrkC K1, mediates the trophic properties of NT3 in cultured Cells(2,6-8). Here we show that homozygous mice defective for TrkC tyrosine protein kinase receptors lack Ia muscle afferent projections to spinal motor neurons and have fewer large myelinated axons in the dorsal root and posterior columns of the spinal cord. These mice display abnormal movements and postures, indicating that NT3/TrkC-dependent sensory neurons may play a primary role in proprioception, the sense of position and movement of the limbs.
C1 EUROPEAN MOLEC BIOL LAB,DIFFERENTIAT PROGRAMME,D-69012 HEIDELBERG,GERMANY.
   WASHINGTON UNIV,SCH MED,DEPT NEUROL & NEUROL SURG,ST LOUIS,MO 63110.
C3 European Molecular Biology Laboratory (EMBL); Washington University (WUSTL)
RP KLEIN, R (corresponding author), BRISTOL MYERS SQUIBB PHARMACEUT RES INST,DEPT MOLEC BIOL,PRINCETON,NJ 08543, USA.
NR 24
TC 554
Z9 621
U1 1
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 249
EP 251
DI 10.1038/368249a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000057
PM 8145824
DA 2026-03-10
ER

PT J
AU RIDDIHOUGH, G
AF RIDDIHOUGH, G
TI A TWIST IN THE TAIL OF HUMAN ENDOTHELIN
SO NATURE
LA English
DT Article
NR 2
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 84
EP 84
DI 10.1038/369084a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000060
PM 8164749
DA 2026-03-10
ER

PT J
AU STEIN, JA
   KURTZ, N
AF STEIN, JA
   KURTZ, N
TI THE SCIENTIFIC LABOR-MARKET IN EUROPE
SO NATURE
LA English
DT Article
AB The United Kingdom, almost alone among European countries, does not have internationalization as an integral part of its education and training policy.
C1 CNRS,LONDON SW7 2JN,ENGLAND.
C3 Centre National de la Recherche Scientifique (CNRS)
RP STEIN, JA (corresponding author), UNIV MANCHESTER,PROGRAMME POLICY RES ENGN SCI & TECHNOL,LONDON OFF,8 JOHN ADAM ST,LONDON WC2N 6EZ,ENGLAND.
NR 0
TC 0
Z9 0
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 234
EP 234
DI 10.1038/370234a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100058
DA 2026-03-10
ER

PT J
AU AMON, RMW
   BENNER, R
AF AMON, RMW
   BENNER, R
TI RAPID-CYCLING OF HIGH-MOLECULAR-WEIGHT DISSOLVED ORGANIC-MATTER IN THE OCEAN
SO NATURE
LA English
DT Article
ID phytoplankton bloom; bacterioplankton growth; north pacific; sea-water; carbon; seawater; bacteria; colloids; oxygen
AB DISSOLVED organic matter (DOM) in the ocean is one of the largest active reservoirs of organic carbon on Earth. It is important to understand the processes by which DOM is recycled, particularly as changes in the oceanic DOM pool could affect atmospheric carbon dioxide concentrations on timescales of 1,000 to 10,000 years (ref. 1). It is commonly believed that low-molecular-weight material, which comprises 65-80% of DOM(2-5), is rapidly remineralized, and that high-molecular-weight material is refractory. But the average age of DOM in the deep ocean is about 6,000 years (ref. 6) which implies that a large proportion of the DOM cycles only very slowly. Here we present a study of the relative bioavailability of low- and high-molecular weight DOM in water samples taken from the northern Gulf of Mexico during a diatom bloom. Bacterial growth and respiration in the presence of high-molecular-weight DOM were respectively three and six times greater than for low-molecular-weight material. Although both of these pools undoubtedly contain mixtures of compounds with varying reactivities and turnover times, our results demonstrate that the bulk of oceanic DOM comprises small molecules that cycle slowly and are relatively unavailabe to microorganisms.
RP AMON, RMW (corresponding author), UNIV TEXAS,INST MARINE SCI,POB 1267,PORT ARANSAS,TX 78373, USA.
NR 31
TC 420
Z9 482
U1 4
U2 130
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 549
EP 552
DI 10.1038/369549a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400045
DA 2026-03-10
ER

PT J
AU ZHANG, YY
   PROENCA, R
   MAFFEI, M
   BARONE, M
   LEOPOLD, L
   FRIEDMAN, JM
AF ZHANG, YY
   PROENCA, R
   MAFFEI, M
   BARONE, M
   LEOPOLD, L
   FRIEDMAN, JM
TI POSITIONAL CLONING OF THE MOUSE OBESE GENE AND ITS HUMAN HOMOLOG
SO NATURE
LA English
DT Article
ID artificial-chromosome library; polymerase chain-reaction; dna fragments; messenger-rna; ob mutation; yeast; identification; mice
AB The mechanisms that balance food intake and energy expenditure determine who will be obese and who will be lean. One of the molecules that regulates energy balance in the mouse is the obese (ob) gene. Mutation of ob results in profound obesity and type II diabetes as part of a syndrome that resembles morbid obesity in humans. The ob gene product may function as part of a signalling pathway from adipose tissue that acts to regulate the size of the body fat depot.
C1 HOWARD HUGHES MED INST,NEW YORK,NY 10021.
   ROCKEFELLER UNIV,NEW YORK,NY 10021.
C3 Howard Hughes Medical Institute; Rockefeller University
NR 49
TC 11209
Z9 13167
U1 8
U2 1229
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 425
EP 432
DI 10.1038/372425a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200046
PM 7984236
DA 2026-03-10
ER

PT J
AU ORENGO, CA
   JONES, DT
   THORNTON, JM
AF ORENGO, CA
   JONES, DT
   THORNTON, JM
TI PROTEIN SUPERFAMILIES AND DOMAIN SUPERFOLDS
SO NATURE
LA English
DT Article
ID structure alignment; globular-proteins; sequences; fold; similarity; family
AB As the protein sequence and structure databases expand rapidly a better understanding of the relationships between proteins is required. A classification is considered that extends the sequence-based superfamilies to include proteins with similar function and three-dimensional structures but no sequence similarity. So far there are only nine protein folds known to recur in proteins having neither sequence nor functional similarity. These folds dominate the structure database, representing more than 30 per cent of all determined structures. This observation has implications for protein-fold recognition.
C1 NATL INST MED RES,MATH BIOL LAB,LONDON NW7 1AA,ENGLAND.
C3 MRC National Institute for Medical Research
RP ORENGO, CA (corresponding author), UNIV LONDON UNIV COLL,DEPT BIOCHEM & MOLEC BIOL,BIOMOLEC STRUCT & MODELLING UNIT,GOWER ST,LONDON WC1E 6BT,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 27
TC 675
Z9 746
U1 0
U2 22
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 631
EP 634
DI 10.1038/372631a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700074
PM 7990952
DA 2026-03-10
ER

PT J
AU BELL, TW
   JOUSSELIN, H
AF BELL, TW
   JOUSSELIN, H
TI SELF-ASSEMBLY OF A DOUBLE-HELICAL COMPLEX OF SODIUM
SO NATURE
LA English
DT Article
ID x-ray crystal; molecular-structure; metal-complexes; ligands; preference; chemistry
AB SPONTANEOUS self-organization of helical and multiple-helical molecular structures occurs on several levels in living organisms. Key examples are alpha-helical polypeptides, double-helical nucleic acids and helical protein structures, including F-actin, microtubules and the protein sheath of the tobacco mosaic virus1. Although the self-assembly of double-helical transition-metal complexes1-15 bears some resemblance to the molecular organization of double-stranded DNA, selection between monohelical, double-helical and triple-helical structures is determined largely by the size and geometrical preference of the tightly bound metal14. Here we present an example of double-helical assembly induced by the weaker and non-directional interactions of an alkali-metal ion with an organic ligand that is pre-organized into a coil. We have characterized the resulting complex by two-dimensional NMR and fast-atom-bombardment mass spectrometry. These results provide a step toward the creation of molecular tubes or ion channels consisting of intertwined coils.
RP BELL, TW (corresponding author), SUNY STONY BROOK,DEPT CHEM,STONY BROOK,NY 11794, USA.
NR 30
TC 104
Z9 107
U1 0
U2 29
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 441
EP 444
DI 10.1038/367441a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900048
PM 8107802
DA 2026-03-10
ER

PT J
AU GAO, S
   DAVIS, PM
   LIU, H
   SLACK, PD
   ZORIN, YA
   MORDVINOVA, VV
   KOZHEVNIKOV, VM
   MEYER, RP
AF GAO, S
   DAVIS, PM
   LIU, H
   SLACK, PD
   ZORIN, YA
   MORDVINOVA, VV
   KOZHEVNIKOV, VM
   MEYER, RP
TI SEISMIC ANISOTROPY AND MANTLE FLOW BENEATH THE BAIKAL RIFT-ZONE
SO NATURE
LA English
DT Article
ID rio-grande rift; azimuthal anisotropy; lithosphere; stations; sks; convection; tectonics; geoscope; basin; range
AB SEISMIC studies have shown that continental rifts such as Lake Baikal and the Great Rift Valley of East Africa are like midocean rifts in that they lie above broad regions of asthenospheric upwarp of much greater extent than the surface expression of rifting(1-4). The direction of mantle flow in such regions ran be investigated using the seismic anisotropy created by flow-induced orientation of mantle olivine crystals(5-8). Seismic studies of the Mid-Atlantic Ridge have revealed upwelling mantle flow beneath the ridge and flow normal to the ridge axis on either side(8-10). Here we present results from an array of seismic stations across the Baikal rift zone in southern Siberia. The splitting in arrival times of SKS seismic waves indicates that the upper mantle beneath the rift zone is anisotropic, with the fast direction (which reflects the direction of mantle how) being horizontal and normal to the rift axis. This suggests that the broad upwarp associated with this continental rift is caused by similar mantle flow to that at mid-ocean rifts. This may help to elucidate the processes involved in continental rifting.
C1 RUSSIAN ACAD SCI, INST EARTHS CRUST, IRKUTSK 664033, RUSSIA.
   UNIV WISCONSIN, DEPT GEOL & GEOPHYS, MADISON, WI 53706 USA.
C3 Russian Academy of Sciences; Irkutsk Science Centre of the Russian Academy of Sciences; Institute of Earth's Crust of Siberian Branch of the Russian Academy of Sciences; University of Wisconsin System; University of Wisconsin Madison
RP GAO, S (corresponding author), UNIV CALIF LOS ANGELES, DEPT EARTH & SPACE SCI, LOS ANGELES, CA 90024 USA.
NR 28
TC 141
Z9 162
U1 0
U2 17
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 149
EP 151
DI 10.1038/371149a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100061
DA 2026-03-10
ER

PT J
AU MOSS, G
   COHEN, S
AF MOSS, G
   COHEN, S
TI PATENTS IN THE PUBLIC-INTEREST
SO NATURE
LA English
DT Article
AB The UH High Court has granted an injunction allowing Chiron Corporation a monopoly in selling hepatitis C virus test kits. The decision will be welcomed by the pharmaceutical and biotechnology industries.
RP MOSS, G (corresponding author), TAYLOR JOYNSON GARRETT,50 VICTORIA EMBANKMENT,LONDON EC4Y 0DX,ENGLAND.
NR 0
TC 1
Z9 1
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 814
EP 814
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200063
PM 7997274
DA 2026-03-10
ER

PT J
AU GAVIS, ER
   LEHMANN, R
AF GAVIS, ER
   LEHMANN, R
TI TRANSLATIONAL REGULATION OF NANOS BY RNA LOCALIZATION
SO NATURE
LA English
DT Article
ID segmentation gene hunchback; posterior determinant nanos; pole cell-formation; drosophila-melanogaster; maternal gene; embryonic polarity; anterior pattern; germ plasm; oskar; protein
AB LOCALIZATION of the maternally synthesized nanos (nos) RNA to the posterior pole of the Drosophila embryo provides the source for a posterior-to-anterior gradient of Nos protein(1,2). Correct spatial regulation of nos activity is essential for normal pattern formation. High local concentrations of Nos protein in the posterior of the embryo are necessary to inhibit translation of the transcription factor Hunchback in this region(3,4), ana thus permit expression of genes required for abdomen formation (see ref. 5 for review). By contrast, misexpression of Nos protein at the anterior of the embryo prevents translation of the anterior morphogen Bicoid, suppressing head and thorax development(1,6-9). Posterior localization of nos RNA is mediated by sequences within the nos 3' untranslated region (3'UTR)(1) and requires the function of eight genes of the 'posterior group'(2,6). Although the unlocalized nos RNA is stable in embryos from females mutant for any of the posterior group genes, these embryos appear to lack nos activity because they develop the abdominal defects characteristic of embryos produced by nos mutant females(2,6,10-14). We report here that unlocalized nos RNA is translationally repressed. Translational repression is mediated by the nos 3'UTR and can be alleviated either by replacement of the 3'UTR with heterologous 3'UTR sequences or by posterior localization. Thus, RNA localization provides a novel mechanism for translational regulation.
C1 MIT, DEPT BIOL, CAMBRIDGE, MA 02142 USA.
C3 Massachusetts Institute of Technology (MIT)
RP GAVIS, ER (corresponding author), MIT, WHITEHEAD INST BIOMED RES, HOWARD HUGHES MED INST, 9 CAMBRIDGE CTR, CAMBRIDGE, MA 02142 USA.
NR 30
TC 260
Z9 311
U1 1
U2 12
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 315
EP 318
DI 10.1038/369315a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900048
PM 7514276
DA 2026-03-10
ER

PT J
AU EDERY, P
   LYONNET, S
   MULLIGAN, LM
   PELET, A
   DOW, E
   ABEL, L
   HOLDER, S
   NIHOULFEKETE, C
   PONDER, BAJ
   MUNNICH, A
AF EDERY, P
   LYONNET, S
   MULLIGAN, LM
   PELET, A
   DOW, E
   ABEL, L
   HOLDER, S
   NIHOULFEKETE, C
   PONDER, BAJ
   MUNNICH, A
TI MUTATIONS OF THE RET PROTOONCOGENE IN HIRSCHSPRUNGS-DISEASE
SO NATURE
LA English
DT Article
AB HIRSCHSPRUNG'S disease (HSCR)1 is a common condition (1 in 5,000 live births) resulting in intestinal obstruction in neonates2 and megacolon in infants and adults3. This disease has been ascribed to the absence of autonomic ganglion cells, which are derived from the neural crest, in the terminal hindgut4. Segregation analyses have suggested incompletely penetrant dominant inheritance in familial HSCR5. Recently, a gene for HSCR has been mapped to chromosome 10q11.2 (refs 6, 7). No recombination was observed between the disease locus and the locus for the RET proto-oncogene8, a protein tyrosine kinase gene expressed in the cells derived from the neural crest9,10. Here we report nonsense and missense mutations in the extracellular domain of RET protein (exons, 2, 3, 5, and 6) in six unrelated probands and show that the mutant genotypes segregate with the disease in HSCR families. Mutations of RET have been previously reported in multiple endocrine neoplasia type 2A (MEN 2A)11,12.  Thus, germ-line mutations of the RET gene may contribute either to developmental anomalies in HSCR or to inherited predisposition to cancer in MEN 2A.
C1 HOP NECKER ENFANTS MALAD,CHIRURG INFANTILE CLIN,SERV GENET MED,149 RUE SEVRES,F-75743 PARIS 15,FRANCE.
   HOP NECKER ENFANTS MALAD,INSERM,U393,UNITE RECH HANDICAPS GENET ENFANT,F-75743 PARIS 15,FRANCE.
   UNIV CAMBRIDGE,DEPT PATHOL,CRC HUMAN CANC GENET RES GRP,CAMBRIDGE CB2 1QP,ENGLAND.
   ST MARYS HOSP,SCH MED,DEPT BIOCHEM & MOLEC GENET,LONDON W2 1PG,ENGLAND.
   HOP LA PITIE SALPETRIERE,INSERM,U194,F-75634 PARIS 13,FRANCE.
   INST CHILD HLTH,MOTHERCARE UNIT CLIN GENET,LONDON WC1N 1EH,ENGLAND.
C3 Assistance Publique Hopitaux Paris (APHP); Universite Paris Cite; Hopital Universitaire Necker-Enfants Malades - APHP; Institut National de la Sante et de la Recherche Medicale (Inserm); Assistance Publique Hopitaux Paris (APHP); Universite Paris Cite; Hopital Universitaire Necker-Enfants Malades - APHP; University of Cambridge; Imperial College London; Institut National de la Sante et de la Recherche Medicale (Inserm); Assistance Publique Hopitaux Paris (APHP); Hopital Universitaire Pitie-Salpetriere - APHP; Sorbonne Universite; University of London; University College London
NR 30
TC 658
Z9 697
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 378
EP 380
DI 10.1038/367378a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000071
PM 8114939
DA 2026-03-10
ER

PT J
AU HATTON, CG
   MAIN, IG
   MEREDITH, PG
AF HATTON, CG
   MAIN, IG
   MEREDITH, PG
TI NONUNIVERSAL SCALING OF FRACTURE LENGTH AND OPENING DISPLACEMENT
SO NATURE
LA English
DT Article
ID faults; iceland; extension; strain; growth; slip; size
AB THE deformation of the Earth's brittle crust is dominated by the formation and growth of faults in response to tectonic loading. The scaling properties of such systems provide clues to the underlying mechanisms of fault propagation. For example, if fault growth were a self-similar process, described by a scaling law that applies in all locations1, this might imply a universal faulting mechanism governed by either constant fracture toughness or constant yield stress. Universal scaling laws have been proposed1-4, but their general applicability remains the subject of some debate5. In the natural environment, strict scale invariance can apply only between well-defined bounds6, and it is known that the Earth's crust has many distinct length scales-ranging from the grain size of rocks and the thickness of sedimentary layers up to the finite width of the seismogenic crust-each of which may vary from place to place. Here we report the scaling properties of two populations of tensile fractures in the Krafla fissure swarm of northeast Iceland (spanning nearly four orders of magnitude in length and five in displacement), which clearly show that the presence of such length scales dramatically alters the scaling behaviour. Despite the geological homogeneity of the region studied, our data cannot be described by a single scaling law.
C1 UNIV LONDON UNIV COLL,DEPT GEOL SCI,LONDON WC1E 6BT,ENGLAND.
C3 University of London; University College London
RP HATTON, CG (corresponding author), UNIV EDINBURGH,GRANT INST GEOL,DEPT GEOL & GEOPHYS,W MAINS RD,EDINBURGH EH9 3JW,MIDLOTHIAN,SCOTLAND.
NR 22
TC 138
Z9 148
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 160
EP 162
DI 10.1038/367160a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000056
DA 2026-03-10
ER

PT J
AU KAS, J
   STREY, H
   SACKMANN, E
AF KAS, J
   STREY, H
   SACKMANN, E
TI DIRECT IMAGING OF REPTATION FOR SEMIFLEXIBLE ACTIN-FILAMENTS
SO NATURE
LA English
DT Article
ID f-actin; dynamics; chain; motion
AB ACCORDING to the reptation model of polymer diffusion(1), a polymer chain exhibits snake-like motion through the entangled mesh of surrounding molecules, in which the undulations of the chain are restricted to a tubelike region(2). The reptation model can account for many of the dynamic properties of entangled polymer solutions and melts, and has received support from observations of block copolymer diffusion across an interface(3); but reptative motion has not previously been imaged directly(4,5). Here we report such a direct observation of reptation, obtained by video microscopy of fluorescently labelled single, semiflexible filaments of actin in a solution of unlabelled actin filaments. From the restricted thermal undulations of these filaments we can measure the diameter of the confining tube, and we also observe the characteristic thermally excited sliding of the filament out of the end of the tube. We find that the chain self-diffusion coefficient decreases approximately linearly as the filament length increases, in agreement with the reptation model.
C1 TECH UNIV MUNICH, DEPT PHYS, BIOPHYS GRP, D-85748 GARCHING, GERMANY.
C3 Technical University of Munich
RP KAS, J (corresponding author), HARVARD UNIV, BRIGHAM & WOMENS HOSP, SCH MED, DIV EXPTL MED, BOSTON, MA 02115 USA.
NR 20
TC 223
Z9 249
U1 0
U2 57
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 226
EP 229
DI 10.1038/368226a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000049
PM 8145821
DA 2026-03-10
ER

PT J
AU SCHLESINGER, ME
   RAMANKUTTY, N
AF SCHLESINGER, ME
   RAMANKUTTY, N
TI AN OSCILLATION IN THE GLOBAL CLIMATE SYSTEM OF PERIOD 65-70 YEARS
SO NATURE
LA English
DT Article
ID singular-spectrum analysis; temperature time-series; solar-cycle; variability; dynamics; length
AB IN addition to the well-known warming of approximately 0.5-degrees-C since the middle of the nineteenth century, global-mean surface temperature records1-4 display substantial variability on timescales of a century or less. Accurate prediction of future temperature change requires an understanding of the causes of this variability; possibilities include external factors, such as increasing greenhouse-gas concentrations5-7 and anthropogenic sulphate aerosols8-10, and internal factors, both predictable (such as El Nino11) and unpredictable (noise12,13). Here we apply singular spectrum analysis 14-20 to four global-mean temperature records1-4, and identify a temperature oscillation with a period of 65-70 years. Singular spectrum analysis of the surface temperature records for 11 geographical regions shows that the 65-70-year oscillation is the statistical result of 50-88-year oscillations for the North Atlantic Ocean ard its bounding Northern Hemisphere continents. These oscillations have obscured the greenhouse warming signal in the North Atlantic and North America. Comparison with previous observations and model simulations suggests that the oscillation arises from predictable internal variability of the ocean-atmosphere system.
RP SCHLESINGER, ME (corresponding author), UNIV ILLINOIS,DEPT ATMOSPHER SCI,105 S GREGORY AVE,URBANA,IL 61801, USA.
NR 34
TC 1209
Z9 1365
U1 3
U2 177
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 723
EP 726
DI 10.1038/367723a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100054
DA 2026-03-10
ER

PT J
AU BUHL, EH
   HALASY, K
   SOMOGYI, P
AF BUHL, EH
   HALASY, K
   SOMOGYI, P
TI DIVERSE SOURCES OF HIPPOCAMPAL UNITARY INHIBITORY POSTSYNAPTIC POTENTIALS AND THE NUMBER OF SYNAPTIC RELEASE SITES
SO NATURE
LA English
DT Article
ID guinea-pig hippocampus; ca1 pyramidal cells; granule cells; dentate gyrus; gaba-a; neurons; interneurons; slices; rat; connections
AB Dual intracellular recordings from microscopically identified neurons in the hippocampus reveal that the synaptic terminals of three morphologically distinct types of interneuron act through GABA(A) receptors. Each type of interneuron forms up to 12 synaptic contacts with a postsynaptic principal neuron, but each interneuron innervates a different domain of the surface of the postsynaptic neuron. Different kinetics of the postsynaptic effects, together with the strategic placement of synapses, indicate that these GABAergic interneurons serve distinct functions in the cortical network.
C1 ATTILA JOZSEF UNIV,DEPT ZOOL,H-6701 SZEGED,HUNGARY.
C3 Szeged University
RP BUHL, EH (corresponding author), UNIV OXFORD,MRC,ANAT NEUROPHARMACOL UNIT,MANSFIELD RD,OXFORD OX1 3TH,OXON,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 45
TC 626
Z9 680
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 823
EP 828
DI 10.1038/368823a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700061
PM 8159242
DA 2026-03-10
ER

PT J
AU LIU, ZG
   SMITH, SW
   MCLAUGHLIN, KA
   SCHWARTZ, LM
   OSBORNE, BA
AF LIU, ZG
   SMITH, SW
   MCLAUGHLIN, KA
   SCHWARTZ, LM
   OSBORNE, BA
TI APOPTOTIC SIGNALS DELIVERED THROUGH THE T-CELL RECEPTOR OF A T-CELL HYBRID REQUIRE THE IMMEDIATE-EARLY GENE NUR77
SO NATURE
LA English
DT Article
ID monoclonal-antibody; activation; death; antigen; thymocytes; fragmentation; degradation; induction
AB ENGAGEMENT of the T-cell antigen receptor (TCR) on immature thymic T cells induces death by apoptosis1-3. Although several lines of evidence indicate that apoptosis requires de novo gene expression, little is known about the molecular pathways that mediate this response.  Here we show that nur77 (refs 4-7), a zinc-finger transcription factor, is expressed in response to TCR engagement in immature T cells and T-cell hybrids. Antisense inhibition of nur77 expression prevents apoptosis in TCR-stimulated cells. nur 7 is also expressed in response to mitogens, but in this case transcription is regulated by 5' upstream elements that are distinct from those used for induction of apoptosis. In addition, polyadenylation is only observed on nur77 transcripts found in condemned cells. These data support a role for nur77 in cell death that may be distinct from that of activation.
C1 UNIV MASSACHUSETTS,DEPT VET & ANIM SCI,AMHERST,MA 01003.
   UNIV MASSACHUSETTS,DEPT BIOL,AMHERST,MA 01003.
   UNIV MASSACHUSETTS,PROGRAM MOLEC & CELLULAR BIOL,AMHERST,MA 01003.
C3 University of Massachusetts System; University of Massachusetts Amherst; University of Massachusetts System; University of Massachusetts Amherst; University of Massachusetts System; University of Massachusetts Amherst
NR 22
TC 513
Z9 568
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 281
EP 284
DI 10.1038/367281a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400059
PM 8121494
DA 2026-03-10
ER

PT J
AU HIROSE, K
   IINO, M
AF HIROSE, K
   IINO, M
TI HETEROGENEITY OF CHANNEL DENSITY IN INOSITOL-1,4,5-SENSITIVE TRISPHOSPHATE-SENSITIVE CA2+ STORES
SO NATURE
LA English
DT Article
ID vascular smooth-muscle; calcium release; fluorescent indicator; intracellular stores; 1,4,5-trisphosphate; cells; mechanism; mobilization; dependence
AB INOSITOL-1,4,5-trisphosphate (InsP(3))-induced Ca2+ release is a key mechanism for intracellular Ca2+ mobilization(1). The rate of Ca2+ release declines progressively with time until a higher concentration of InsP(3) is added, which is referred to as the incremental detection mechanism(2). Two hypotheses have been postulated to explain these complex kinetics: (1) Ca2+ stores consist of multiple compartments (quanta) with different sensitivities to InsP(3) (refs 3-7), and (2) the rate of Ca2+ release is modulated by the Ca2+ concentration in the lumen of Ca2+ stores(8-12). We studied this phenomenon by real-time measurement of the luminal Ca2+ concentration of Ca2+ stores using a Ca2+-sensitive fluorescent dye, but our results were not explained by either of these hypotheses. Here we report that the complex kinetics of Ca2+ release results from the heterogeneous density of equally InsP(3)-sensitive channels on the Ca2+ stores. This heterogeneity creates Ca2+ stores with apparently different sensitivities to InsP(3), which may have different functions in Ca2+ mobilization.
RP HIROSE, K (corresponding author), UNIV TOKYO, FAC MED, DEPT PHARMACOL, BUNKYO KU, TOKYO 113, JAPAN.
NR 29
TC 114
Z9 118
U1 0
U2 1
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 791
EP 794
DI 
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200056
PM 7997268
DA 2026-03-10
ER

PT J
AU IBATA, RA
   GILMORE, G
   IRWIN, MJ
AF IBATA, RA
   GILMORE, G
   IRWIN, MJ
TI A DWARF SATELLITE GALAXY IN SAGITTARIUS
SO NATURE
LA English
DT Article
AB WE have detected a large, extended group of comoving stars in the direction of the Galactic Centre, which we interpret as belonging to a dwarf galaxy that is closer to our own Galaxy than any other yet known. Located in the constellation of Sagittarius, and on the far side of the Galactic Centre, it has not previously been seen because of the large number of foreground stars (in the Milky Way) in that direction. Following convention, we propose to call it the Sagittarius dwarf galaxy. Its properties are similar to those of the eight other dwarf spheroidal companions to the Milky Way, and it is comparable in size and luminosity to the largest of them-the Fornax system. The Sagittarius dwarf is elongated towards the plane of the Milky Way, suggesting that it is undergoing some tidal disruption before being absorbed by the Milky Way.
C1 ROYAL GREENWICH OBSERV,CAMBRIDGE CB3 0EZ,ENGLAND.
C3 University of Cambridge
RP IBATA, RA (corresponding author), UNIV CAMBRIDGE,INST ASTRON,MADINGLEY RD,CAMBRIDGE CB3 0HA,ENGLAND.
NR 10
TC 1294
Z9 1406
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 194
EP 196
DI 10.1038/370194a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100043
DA 2026-03-10
ER

PT J
AU PEKAREK, KJ
   JACOB, JS
   MATHIOWITZ, E
AF PEKAREK, KJ
   JACOB, JS
   MATHIOWITZ, E
TI DOUBLE-WALLED POLYMER MICROSPHERES FOR CONTROLLED DRUG-RELEASE
SO NATURE
LA English
DT Article
ID polyanhydride microspheres; solvent removal; microencapsulation; morphology; systems; coacervation
AB ONE approach to the controlled release of drugs involves incorporation of the drug molecules into the matrix of microscopic polymer spheres or capsules1-10. Existing methods for preparing such microparticles do not, however, always guarantee a constant release rate, for example because drug molecules may be trapped preferentially at the surface, because they have to diffuse through an increasing thickness of polymer when the particles are non-eroding or because the surface area changes for eroding particles. In other situations pulsed release may be required-an application to which simple polymer microspheres do not readily lend themselves. Multi-walled microspheres might solve some of these problems. Here we describe a one-step process for preparing double-walled polymer microspheres with diameters ranging from about 20 to 1,000 micrometres. Our technique11 involves the phase separation of a polymer mixture owing to solvent evaporation: with an appropriate choice of interfacial tensions and evaporation rate, a spherical droplet of one polymer becomes coated with a highly uniform layer of the other. This process, which might be adapted to yield multi-walled microspheres, should make possible the engineering of highly specific drug-release properties.
C1 BROWN UNIV,DIV BIOL & MED,PROVIDENCE,RI 02912.
C3 Brown University
NR 16
TC 247
Z9 310
U1 1
U2 111
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 258
EP 260
DI 10.1038/367258a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400051
PM 8121490
DA 2026-03-10
ER

PT J
AU SOLOMON, JA
   PELLI, DG
AF SOLOMON, JA
   PELLI, DG
TI THE VISUAL FILTER MEDIATING LETTER IDENTIFICATION
SO NATURE
LA English
DT Article
ID spatial-frequency; human-vision; discrimination; masking; noise; efficiency; contrast; shape
AB WE hear periodic sounds, or tones, by means of parallel auditory filters, each tuned to a band of temporal frequency(1), and we see periodic patterns, or gratings, by means of parallel visual filters, each tuned to a band of spatial frequency(2). Beyond helping us to see gratings, do these visual filters participate in everyday tasks such as reading and object recognition? After all, grating visibility only requires the distinguishing of pattern from blank, whereas object recognition, for example letter identification, requires classification by the observer into one of many learned categories. Here we make use of results from hearing research(3), applying to vision a noise-masking paradigm that reveals the filter(s) mediating any threshold task. We find that letter-identificatian and grating-detection filters are identical, showing that the recognition of these objects at one size is mediated and constrained by a single visual filter, or 'channel'.
C1 SYRACUSE UNIV,INST SENSORY RES,SYRACUSE,NY 13244.
C3 Syracuse University
NR 30
TC 265
Z9 290
U1 1
U2 24
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 395
EP 397
DI 10.1038/369395a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400055
PM 8196766
DA 2026-03-10
ER

PT J
AU MORRISON, NA
   QI, JC
   TOKITA, A
   KELLY, PJ
   CROFTS, L
   NGUYEN, TV
   SAMBROOK, PN
   EISMAN, JA
AF MORRISON, NA
   QI, JC
   TOKITA, A
   KELLY, PJ
   CROFTS, L
   NGUYEN, TV
   SAMBROOK, PN
   EISMAN, JA
TI PREDICTION OF BONE-DENSITY FROM VITAMIN-D RECEPTOR ALLELES
SO NATURE
LA English
DT Article
ID osteocalcin gene; physical-fitness; mineral density; femoral-neck; mass; twin; osteoporosis; determinants; spine; women
AB BONE density achieved in early adulthood is the major determinant of risk of osteoporotic fracture. Up to 60% of women1,2 suffer osteoporotic fractures as a result of low bone density2, which is under strong genetic control-3-6 acting through effects on bone turnover 7, 8. Here we show that common allelic variants in the gene encoding the vitamin D receptor9 can be used to predict differences in bone density, accounting for up to 75% of the total genetic effect on bone density in healthy individuals. The genotype associated with lower bone density was overrepresented in postmenopausal women with bone densities more than 2 standard deviations below values in young normal women. The molecular mechanisms by which bone density is regulated by the vitamin D receptor gene are not certain, although allelic differences in the 3' untranslated region may alter messenger RNA levels. These findings could open new avenues to the development and targeting of prophylactic interventions. It follows that other pathophysiological processes considered to be subject to complex multifactorial genetic regulation may also be modulated by a single gene with pleiotropic transcriptional actions.
RP MORRISON, NA (corresponding author), ST VINCENTS HOSP,GARVAN INST MED RES,DIV BONE & MINERAL RES,DARLINGHURST,NSW 2010,AUSTRALIA.
NR 21
TC 1683
Z9 1906
U1 4
U2 51
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 284
EP 287
DI 10.1038/367284a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400060
PM 8161378
DA 2026-03-10
ER

PT J
AU DIXON, A
   ROSS, D
   OMALLEY, SLC
   BURKE, T
AF DIXON, A
   ROSS, D
   OMALLEY, SLC
   BURKE, T
TI PATERNAL INVESTMENT INVERSELY RELATED TO DEGREE OF EXTRA-PAIR PATERNITY IN THE REED BUNTING
SO NATURE
LA English
DT Article
ID dunnocks prunella-modularis; hirundo-rustica; purple martins; parental care; copulations; behavior; dna; evolution; female; mates
AB EXTRA-PAIR copulations, in which a female copulates with a male other than her mate, are known to occur in many bird species(1). Here we study a wild population of reed buntings, Emberiza schoeniclus, using single-locus DNA fingerprinting(2,3) and find an exceptionally high proportion of extra-pair paternity that accounts for 55% (118/216) of young and 86% (50/58) of nests. Twelve pairs each raised two broods in a single season in which the proportion of extra-pair young differed between the two broods. A highly significant relationship between a male's parental investment and his degree of paternity was revealed by a comparison between the first and second brood of each pair, with more paternal care usually being provided at the nest that contained a lower proportion of extra-pair young. We propose that males can assess their likelihood of paternity and adjust their nestling provisioning rates accordingly.
RP DIXON, A (corresponding author), UNIV LEICESTER,DEPT ZOOL,LEICESTER LE1 7RH,LEICS,ENGLAND.
NR 24
TC 302
Z9 332
U1 0
U2 70
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 698
EP 700
DI 10.1038/371698a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300054
DA 2026-03-10
ER

PT J
AU BREITSCHWERDT, D
   SCHMUTZLER, T
AF BREITSCHWERDT, D
   SCHMUTZLER, T
TI DELAYED RECOMBINATION AS A MAJOR SOURCE OF THE SOFT-X-RAY BACKGROUND
SO NATURE
LA English
DT Article
ID star formation; disk; halo; galaxy; gas
AB THE origin of the soft X-ray background radiation has remained masterious(1) since its discovery(2), although it is clear from the lack of absorption of the tow-energy X-rays that there must be a strong local contribution(3). Recent results(4,5) demonstrate, however, that there are significant more distant contributions, whose origins are also unclear. Here we propose an explanation for both the local and more distant contributions to the soft X-ray background-they seem to arise from the rapid adiabatic expansion of hot gas, driven by the explosions of massive stars. This hot gas cools quickly, 'freezing in' highly ionized atomic states. The X-ray emission arises from the delayed recombination of ions and electrons at relatively low temperatures, and is therefore distinct from the more usual line emission excited by collisions with electrons. The X-ray flux is thus relatively insensitive to the local gas kinetic temperature, as the gas is far from ionization equilibrium.
C1 INST THEORET ASTROPHYS, D-69120 HEIDELBERG, GERMANY.
C3 Ruprecht Karls University Heidelberg
RP BREITSCHWERDT, D (corresponding author), MAX PLANCK INST KERNPHYS, POSTFACH 103 980, D-69117 HEIDELBERG, GERMANY.
NR 33
TC 111
Z9 113
U1 0
U2 0
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 774
EP 777
DI 10.1038/371774a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800051
DA 2026-03-10
ER

PT J
AU MARTIN, JR
   RAIBAUD, A
   OLLO, R
AF MARTIN, JR
   RAIBAUD, A
   OLLO, R
TI TERMINAL PATTERN ELEMENTS IN DROSOPHILA EMBRYO INDUCED BY THE TORSO-LIKE PROTEIN
SO NATURE
LA English
DT Article
ID receptor tyrosine kinase; gene; melanogaster; sequence; polarity; sites
AB THE genes torso (tor)1 and torso-like (tsl)2 are two of the Drosophila maternal group genes implicated in a receptor tyrosine kinase signalling pathway that specifies terminal cell fate (reviewed in ref. 3). Loss-of function mutations in these loci cause an identical phenotype in which pattern elements from the anterior (acron) and posterior (telson) ends have been deleted. We have cloned the tsl gene and demonstrate here that, in agreement with previous genetic data, it encodes a protein that is secreted and whose transcription is restricted to specialized categories of follicle cells localized at the poles of the egg chamber. At early blastoderm, stage, tsl protein forms a symmetrical concentration gradient at the poles on the surface of the devitellinized embryo. Unrestricted expression of the tsl protein in tsl female mutants induces terminal pattern elements and suppresses the formation of abdomen in embryos. These results suggest that the tsl protein is the ligand that binds to the torso receptor.
RP MARTIN, JR (corresponding author), INST PASTEUR, BIOL MOLEC DROSOPHILE LAB, 25 RUE DOCTEUR ROUX, F-75724 PARIS 15, FRANCE.
NR 25
TC 85
Z9 91
U1 0
U2 14
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 741
EP 745
DI 10.1038/367741a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100060
PM 8107870
DA 2026-03-10
ER

PT J
AU TAYLOR, SJ
   SHALLOWAY, D
AF TAYLOR, SJ
   SHALLOWAY, D
TI AN RNA-BINDING PROTEIN ASSOCIATED WITH SRC THROUGH ITS SH2 AND SH3 DOMAINS IN MITOSIS
SO NATURE
LA English
DT Article
ID molecular-cloning; activation; p60c-src; phosphorylation; pp60c-src
AB THE tyrosine kinase activity of c-Src is stimulated during mitosis by dephosphorylation of its regulatory tyrosine residue(1-3). This is associated with increased accessibility of its Src homology-2 (SH2) domain for binding a phosphotyrosine-containing peptide(4). But physiological targets of activated c-Src in mitosis have not yet been identified. Here we report that a 68K protein (p68) becomes tyrosine-phosphorylated and physically associates with Src during mitosis in mouse fibroblasts. p68 independently binds the Src SH2 and SH3 domains in vitro and both domains are required for p68 phosphorylation and binding in vivo. p68 is closely related to the p62 protein that is associated with the Ras GTPase-activating protein (GAP)(5) and selectively binds, directly or indirectly, polyribonucleotides. Because the Src SH3 domain also binds heterogeneous nuclear ribonucleoprotein K, these results raise the intriguing possibility that c-Src may regulate the processing, trafficking or translation of RNA in a cell-cycle-dependent manner.
RP TAYLOR, SJ (corresponding author), CORNELL UNIV,BIOCHEM MOLEC & CELL BIOL SECT,ITHACA,NY 14853, USA.
NR 26
TC 398
Z9 434
U1 1
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 867
EP 871
DI 10.1038/368867a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700075
PM 7512694
DA 2026-03-10
ER

PT J
AU VAJANAPHANICH, M
   SCHULTZ, C
   RUDOLF, MT
   WASSERMAN, M
   ENYEDI, P
   CRAXTON, A
   SHEARS, SB
   TSIEN, RY
   BARRETT, KE
   TRAYNORKAPLAN, A
AF VAJANAPHANICH, M
   SCHULTZ, C
   RUDOLF, MT
   WASSERMAN, M
   ENYEDI, P
   CRAXTON, A
   SHEARS, SB
   TSIEN, RY
   BARRETT, KE
   TRAYNORKAPLAN, A
TI LONG-TERM UNCOUPLING OF CHLORIDE SECRETION FROM INTRACELLULAR CALCIUM LEVELS BY INS(3,4,5,6)P-4
SO NATURE
LA English
DT Article
ID epithelial-cell line; inositol tetrakisphosphate; rat-liver; purification; phosphates; transport
AB OSMOREGULATION, inhibitory neurotransmission and pH balance depend on chloride ion (Cl-) flux. In intestinal epithelial cells, apical Cl- channels control salt and fluid secretion and are, in turn, regulated by agonists acting through cyclic nucleotides and internal calcium ion concentration ([Ca2+](i))(1-3). Recently, we found that muscarinic pretreatment prevents [Ca2+](i) increases from eliciting Cl- secretion in T-84 colonic epithelial cells(4). By studying concomitant inositol phosphate metabolism, ae have now identified D-myo-inositol 3,4,5,6-tetrakisphosphate (Ins(3,4,5,6)P-4), as the inositol phosphate most likely to mediate this uncoupling. A novel, membrane-permeant ester prepared by total synthesis delivers Ins(3,4,5,6)P-4 intracellularly and confirms that this emerging messenger(5) does inhibit Cl- flux resulting from thapsigargin- or histamine-induced [Ca2+](i) elevations.
C1 UNIV CALIF SAN DIEGO,SCH MED,DEPT MED 8414,LA JOLLA,CA 92093.
   UNIV CALIF SAN DIEGO,SCH MED,DEPT PHARMACOL,LA JOLLA,CA 92093.
   UNIV CALIF SAN DIEGO,SCH MED,HOWARD HUGHES MED INST,LA JOLLA,CA 92093.
   UNIV BREMEN,INST ORGAN CHEM,W-2800 BREMEN,GERMANY.
   NIEHS,CELLULAR & MOLEC PHARMACOL LAB,RES TRIANGLE PK,NC 27709.
C3 University of California System; University of California San Diego; University of California System; University of California San Diego; Howard Hughes Medical Institute; University of California System; University of California San Diego; University of Bremen; National Institutes of Health (NIH) - USA; NIH National Institute of Environmental Health Sciences (NIEHS)
NR 20
TC 171
Z9 181
U1 1
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 711
EP 714
DI 10.1038/371711a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300059
PM 7935818
DA 2026-03-10
ER

PT J
AU LIAN, JP
   STONE, S
   JIANG, Y
   LYONS, P
   FERRONOVICK, S
AF LIAN, JP
   STONE, S
   JIANG, Y
   LYONS, P
   FERRONOVICK, S
TI YPT1P IMPLICATED IN V-SNARE ACTIVATION
SO NATURE
LA English
DT Article
ID integral membrane-protein; endoplasmic-reticulum; golgi-complex; vesicular transport; secretory pathway; yeast; fusion; er; encodes; identification
AB SYNAPTOBREVIN-LIKE membrane proteins that reside on transport vesicles, called the vesicle SNARE (v-SNARE), play a key role in ensuring that a vesicle targets and fuses with its correct acceptor compartment(1-3). Here we show that Bos1p, the v-SNARE of yeast endoplasmic reticulum-to-Golgi transport vesicles, pairs with another integral membrane protein of similar topology (Sec22p) on vesicles. This pairing, which appears to require functional Ypt1p (Rab in mammalian cells), may aid the activity of Bos1p on this compartment. These findings suggest that Rabs regulate the specificity of membrane fusion by selectively activating the v-SNARE on carrier vesicles. Because the v-SNARE resides on more than one membrane, such a regulated activation step may be necessary to prevent the premature fusion of donor and acceptor compartments(4).
C1 YALE UNIV,SCH MED,DEPT CELL BIOL,NEW HAVEN,CT 06510.
   YALE UNIV,SCH MED,HOWARD HUGHES MED INST,NEW HAVEN,CT 06510.
C3 Yale University; Howard Hughes Medical Institute; Yale University
NR 21
TC 175
Z9 185
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 698
EP 701
DI 10.1038/372698a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700092
PM 7990964
DA 2026-03-10
ER

PT J
AU WANG, ZQ
   FUNG, MR
   BARLOW, DP
   WAGNER, EF
AF WANG, ZQ
   FUNG, MR
   BARLOW, DP
   WAGNER, EF
TI REGULATION OF EMBRYONIC GROWTH AND LYSOSOMAL TARGETING BY THE IMPRINTED IGF2/MPR GENE
SO NATURE
LA English
DT Article
ID mannose 6-phosphate receptor; factor-ii; tme locus; mouse; cells; activation; disruption; proteins; binding; defects
AB THE receptor for insulin-like growth factor type 2, also known as the cation-independent mannose-6-phosphate receptor (Igf2/Mpr), is a multifunctional receptor thought to play a role in lysosomal targeting, cell growth and signal transduction(1-8). Igf2/Mpr has been mapped to the mouse Tme(9) locus and shown to be an imprinted gene(10), which further suggests a role in embryonic growth regulation. To define the functions of Igf2/Mpr, we have generated mice lacking this gene. We report here that maternal inheritance of an Igf2/Mpr null allele (-/+) as well as homozygosity for the inactive allele (-/-) is generally lethal at birth and mutants are about 30% larger, indicating that maternal expression of Igf2/Mpr is essential for late embryonic development and growth regulation. The phenotype is probably caused by an excess of Igf2 because the introduction of an Igf2 null allele rescued the Igf2/Mpr mutant mice. Mutant mice also have organ and skeletal abnormalities and missort mannose-6-phosphate-tagged proteins. A few (-/+) mice reactivated their paternal Igf2/Mpr allele in some tissues and survived to adults. But no (-/-) mice survived, indicating a role for the reactivated paternal allele in postnatal survival.
RP WANG, ZQ (corresponding author), RES INST MOLEC PATHOL,DR BOHR GASSE 7,A-1030 VIENNA,AUSTRIA.
NR 30
TC 406
Z9 451
U1 0
U2 21
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 464
EP 467
DI 10.1038/372464a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200057
PM 7984240
DA 2026-03-10
ER

PT J
AU FIELD, MH
   HUNTLEY, B
   MULLER, H
AF FIELD, MH
   HUNTLEY, B
   MULLER, H
TI EEMIAN CLIMATE FLUCTUATIONS OBSERVED IN A EUROPEAN POLLEN RECORD
SO NATURE
LA English
DT Article
ID greenland ice cores; response surfaces; last; reconstruction; vegetation; remains; gisp2
AB RECENT ice-core data from Greenland(1,2) suggest that the climate during the last interglacial period (the Eemian) was more unstable than that of the Holocene (about 10,000 years ago to the present), being characterized in particular by a series of cold episodes each lasting about 70 to 750 years. Subsequent analysis of a second Greenland ice core(3,4), however, failed to corroborate the details of these Eemian climate fluctuations, a result that may be attributable to the effects of ice flow(4). To resolve this discrepancy, it is imperative to seek alternative sources of information about the Eemian climate. Here we present climate reconstructions from pollen data from the annually laminated Eemian lake-sediment record at Bispingen(5) and from the Eemian and Holocene peat records at La Grande Pile(6). The former record indicates that an initially warm period of 2,900 yr was followed by cooling and a series oi colder episodes, one of which had winter temperatures comparable to those at the end of the preceding cold stage. The latter records show greater climate instability during the Eemian than the Holocene. These results are in broad agreement with those from the GRIP ice core, but contrast both with the GISP2 core(3,4) and with recent high-resolution marine records from the North Atlantic(7,8).
C1 UNIV DURHAM,DEPT BIOL SCI,ENVIRONM RES CTR,DURHAM DH1 3LE,ENGLAND.
   BUNDESANSTALT GEOWISSENSCH & ROHSTOFFE,D-30631 HANNOVER 51,GERMANY.
C3 Durham University
RP FIELD, MH (corresponding author), UNIV CAMBRIDGE,SCH BOT,SUBDEPT QUATERNAY RES,DOWNING ST,CAMBRIDGE CB2 3EA,ENGLAND.
NR 28
TC 144
Z9 153
U1 2
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 779
EP 783
DI 10.1038/371779a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800053
DA 2026-03-10
ER

PT J
AU TSANG, SC
   CHEN, YK
   HARRIS, PJF
   GREEN, MLH
AF TSANG, SC
   CHEN, YK
   HARRIS, PJF
   GREEN, MLH
TI A SIMPLE CHEMICAL METHOD OF OPENING AND FILLING CARBON NANOTUBES
SO NATURE
LA English
DT Article
ID graphitic carbon
AB Since carbon nanotubes(1) were first synthesized in macroscopic quantities(2), it has become possible to explore their physical and chemical characteristics. There has been much speculation(3) about the properties of materials encapsulated within the tubes, but experimental studies of this issue require a reliable means of opening and filling the tubes. Various approaches have been developed for opening Up(4-6) th, tube ends and encapsulating material(4,6,7), but these work only for a limited range of materials or in low yield. Here we describe a general method that allows carbon nanotubes to be opened at the end and filled with a variety of metal oxides using wet chemical techniques. We anticipate that this method will lead to extensive study of the chemistry and physics of filled nanotubes, which might find applications in catalysis, separation and storage technology and in the development of materials with new magnetic and electrical properties.
C1 UNIV OXFORD,CTR CATALYSIS,INORGAN CHEM LAB,OXFORD OX1 3QR,ENGLAND.
C3 University of Oxford
NR 13
TC 1301
Z9 1503
U1 4
U2 369
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 159
EP 162
DI 10.1038/372159a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800049
DA 2026-03-10
ER

PT J
AU STORM, EE
   HUYNH, TV
   COPELAND, NG
   JENKINS, NA
   KINGSLEY, DM
   LEE, SJ
AF STORM, EE
   HUYNH, TV
   COPELAND, NG
   JENKINS, NA
   KINGSLEY, DM
   LEE, SJ
TI LIMB ALTERATIONS IN BRACHYPODISM MICE DUE TO MUTATIONS IN A NEW MEMBER OF THE TGF-BETA-SUPERFAMILY
SO NATURE
LA English
DT Article
ID mouse; bone; morphogenesis; protein; linkage; family; locus
AB THE mutation brachypodism (bp) alters the length and number of bones in the limbs of mice but spares the axial skeleton1,2. It illustrates the importance of specific genes in controlling the morphogenesis of individual skeletal elements in the tetrapod limb3,4. We now report the isolation of three new members of the transforming growth factor-beta (TGF-beta) superfamily5 (growth/differentiation factors (GDF) 5, 6 and 7) and show by mapping, expression patterns and sequencing that mutations in Gdf5 are responsible for skeletal alterations in bp mice. GDF5 and the closely related GDF6 and GDF7 define a new subgroup of factors related to known bone- and cartilage-inducing molecules, the bone morphogenetic proteins (BMPs)6.  Studies of Bmp5 mutations in short ear mice have shown that at least one other BMP gene is also required for normal skeletal development7. The highly specific skeletal alterations in bp and short ear mice suggest that different members of the BMP family control the formation of different morphological features in the mammalian skeleton.
C1 STANFORD UNIV,MED CTR,SCH MED,DEPT DEV BIOL,BECKMAN CTR B300,STANFORD,CA 94305.
   JOHNS HOPKINS UNIV,SCH MED,DEPT MOLEC BIOL & GENET,BALTIMORE,MD 21205.
   NCI,FREDERICK CANC RES & DEV CTR,ABL BASIC RES PROGRAM,MAMMALIAN GENET LAB,FREDERICK,MD 21702.
C3 Stanford University; Johns Hopkins University; Science Applications International Corporation (SAIC); SAIC-Frederick; National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI)
NR 26
TC 750
Z9 846
U1 0
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 639
EP 643
DI 10.1038/368639a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200062
PM 8145850
DA 2026-03-10
ER

PT J
AU SCHUCHARDT, A
   DAGATI, V
   LARSSONBLOMBERG, L
   COSTANTINI, F
   PACHNIS, V
AF SCHUCHARDT, A
   DAGATI, V
   LARSSONBLOMBERG, L
   COSTANTINI, F
   PACHNIS, V
TI DEFECTS IN THE KIDNEY AND ENTERIC NERVOUS-SYSTEM OF MICE LACKING THE TYROSINE KINASE RECEPTOR RET
SO NATURE
LA English
DT Article
ID mouse embryo; protein; cells; differentiation; genes
AB RECEPTOR tyrosine kinases (RTKs) are cell-surface molecules that transduce signals for cell growth and differentiation1. The RTK encoded by the c-ret proto-oncogene2-5 is rearranged and constitutively activated in a large proportion of thyroid papillary carcinomas6, and germ-line point mutations in c-ret seem to be responsible for the dominantly inherited cancer syndromes multiple endocrine neoplasia (MEN) types 2A7,8 and B-9. The gene is expressed in the developing central and peripheral nervous systems (sensory, autonomic and enteric ganglia) and the excretory system (Wolffian duct and ureteric bud epithelium) of mice, indicating that it may play a role in normal development5. Here we show that mice homozygous for a targeted mutation in c-ret develop to term, but die soon after birth, showing renal agenesis or severe dysgenesis, and lacking enteric neurons throughout the digestive tract. Ret is thus an essential component of a signalling pathway required for renal organogenesis and enteric neurogenesis.
C1 NATL INST MED RES,GENE STRUCT & EXPRESS LAB,RIDGEWAY,MILL HILL,LONDON NW7 1AA,ENGLAND.
   COLUMBIA UNIV COLL PHYS & SURG,DEPT GENET & DEV,NEW YORK,NY 10032.
   COLUMBIA UNIV COLL PHYS & SURG,DEPT PATHOL,NEW YORK,NY 10032.
C3 MRC National Institute for Medical Research; Columbia University; Columbia University
NR 34
TC 1373
Z9 1545
U1 0
U2 37
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 380
EP 383
DI 10.1038/367380a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000072
PM 8114940
DA 2026-03-10
ER

PT J
AU NEER, EJ
   SCHMIDT, CJ
   NAMBUDRIPAD, R
   SMITH, TF
AF NEER, EJ
   SCHMIDT, CJ
   NAMBUDRIPAD, R
   SMITH, TF
TI THE ANCIENT REGULATORY-PROTEIN FAMILY OF WD-REPEAT PROTEINS
SO NATURE
LA English
DT Article
ID beta-transducin repeats; saccharomyces-cerevisiae; binding protein; gene-product; drosophila enhancer; negative regulator; early evolution; gamma-subunits; cdc4 gene; yeast
AB WD proteins are made up of highly conserved repeating units usually ending with Trp-Asp (WD). They are found in all eukaryotes but not in prokaryotes. They regulate cellular functions, such as cell division, cell-fate determination, gene transcription, transmembrane signalling, mRNA modification and vesicle fusion. Here we define the common features of the repeating units, and criteria for grouping such proteins into functional subfamilies.
C1 HARVARD UNIV,SCH MED,BOSTON,MA.
   BOSTON UNIV,DEPT PHARMACOL,BOSTON,MA 02215.
   BOSTON UNIV,BIOMOLEC ENGN RES CTR,BOSTON,MA 02215.
C3 Harvard University; Harvard Medical School; Boston University; Boston University
RP NEER, EJ (corresponding author), BRIGHAM & WOMENS HOSP,DEPT MED,75 FRANCIS ST,BOSTON,MA 02115, USA.
NR 68
TC 1345
Z9 1529
U1 1
U2 86
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 297
EP 300
DI 10.1038/371297a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400042
PM 8090199
DA 2026-03-10
ER

PT J
AU RUBIN, KH
   MACDOUGALL, JD
   PERFIT, MR
AF RUBIN, KH
   MACDOUGALL, JD
   PERFIT, MR
TI PO-210-PB-210 DATING OF RECENT VOLCANIC-ERUPTIONS ON THE SEA-FLOOR
SO NATURE
LA English
DT Article
ID east pacific rise; radon daughters; fuca ridge; magma; emission; po-210; juan
AB THE globe-encircling mid-ocean ridge system accounts for most of the Earth's volcanism and influences its heat budget, morphology and the composition of the oceans. It is therefore important to constrain the size, frequency and compositional variability of ridge eruptions, but this is made difficult by the remoteness of much of the sea floor and the paucity of applicable radioactive chronometers. Remote monitoring has provided indirect evidence for active ridge volcanism(1-3), which in some cases has been strengthened by submersible observations(4-5), but it has not been possible to date these eruptions directly. Here we present a new chronometer based on Po-210-Pb-210 radioactive disequilibrium, which allows us to date glassy eruption products within a few years of their eruption. Our first results, on lavas from 9 degrees 50' N on the East Pacific Rise, confirm that the ridge erupted only months before sample collection, and indicate that the eruptions extended over at least one year. The chronometer begins with Po volatilization during eruption (all glasses analysed were 75-100% degassed). A crystalline pillow interior was <20% degassed, however, implying that the flow surface may control Po degassing during deep submarine eruptions. Although the Po-210-Pb-210 chronometer is useful for only a short time-frame, it should prove valuable for dating recent but unobserved submarine eruptions and determining details of eruptive sequences.
C1 UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,LA JOLLA,CA 92093.
   UNIV FLORIDA,DEPT GEOL,GAINESVILLE,FL 32611.
C3 University of California System; University of California San Diego; Scripps Institution of Oceanography; State University System of Florida; University of Florida
RP RUBIN, KH (corresponding author), UNIV HAWAII,HAWAII CTR VOLCANOL,SCH OCEAN & EARTH SCI & TECHNOL,DEPT GEOL & GEOPHYS,HONOLULU,HI 96822, USA.
NR 25
TC 124
Z9 137
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 841
EP 844
DI 10.1038/368841a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700067
DA 2026-03-10
ER

PT J
AU HARTMANN, E
   SOMMER, T
   PREHN, S
   GORLICH, D
   JENTSCH, S
   RAPOPORT, TA
AF HARTMANN, E
   SOMMER, T
   PREHN, S
   GORLICH, D
   JENTSCH, S
   RAPOPORT, TA
TI EVOLUTIONARY CONSERVATION OF COMPONENTS OF THE PROTEIN TRANSLOCATION COMPLEX
SO NATURE
LA English
DT Article
ID signal recognition particle; escherichia-coli; endoplasmic-reticulum; saccharomyces-cerevisiae; 4.5s rna; yeast; ribonucleoprotein; reconstitution; sufficient; insertion
AB PROTEIN translocation into the mammalian endoplasmic reticulum requires the Sec61p complex, which consists of three membrane proteins(1). The alpha-subunit, the homologue of Sec61p of yeast(2-4), shows some similarity to SecYp(5), a key component of the protein export apparatus of bacteria(6,7). In Escherichia coli, SecYp is also associated with two other proteins (SecEp and band-1 protein)(8,9). We have now determined the sequences of the beta- and gamma-subunits of the mammalian Sec61p complex. Sec61-gamma is homologous to SSS1p, a suppressor of sec61 mutants in Saccharomyces cerevisiae, and can functionally replace it in yeast cells. Moreover, Sec61-gamma and SSSIp are structurally related to SecEp of E. coli and to putative homologues in various other bacteria. At least two subunits of the Sec61/SecYp complex therefore seem to be keg components of the protein translocation apparatus in all classes of organisms.
C1 MAX DELBRUCK CTR MOLEC MED, D-12135 BERLIN, GERMANY.
   HUMBOLDT UNIV BERLIN, INST BIOCHEM, D-10115 BERLIN, GERMANY.
   UNIV HEIDELBERG, CTR MOLEC BIOL, ZMBH, D-69120 HEIDELBERG, GERMANY.
C3 Helmholtz Association; Max Delbruck Center for Molecular Medicine; Humboldt University of Berlin; Ruprecht Karls University Heidelberg
NR 26
TC 238
Z9 269
U1 1
U2 6
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 654
EP 657
DI 10.1038/367654a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800057
PM 8107851
DA 2026-03-10
ER

PT J
AU TAIRA, M
   OTANI, H
   SAINTJEANNET, JP
   DAWID, IB
AF TAIRA, M
   OTANI, H
   SAINTJEANNET, JP
   DAWID, IB
TI ROLE OF THE LIM CLASS HOMEODOMAIN PROTEIN XLIM-1 IN NEURAL AND MUSCLE INDUCTION BY THE SPEMANN ORGANIZER IN XENOPUS
SO NATURE
LA English
DT Article
ID messenger-rnas; dna-binding; gene; expression; mesoderm; domain; laevis; embryos; noggin; plate
AB LIKE all known LIM class homeobox genes, Xlim-1 encodes a protein with two tandemly repeated cysteine-rich LIM domains upstream of the homeodomain(1). In Xenopus laevis, Xlim-1 is specifically expressed in the Spemann organizer, whose major functions include neural induction and dorsalization of ventral mesoderm(2-4). From RNA injection experiments we conclude here that: (1) the LIM domains behave as negative regulatory domains; (2) LIM domain mutants of Xlim-1 elicited neural differentiation in animal explants; (3) mutant, and to a lesser extent wild-type, Xlim-1 enhanced muscle formation after coinjection with Xbra; (4) both of these activities are mediated by extracellular signals as seen in combined explant experiments;. (5) Xlim-1 mutants activated goosecoid (gsc) expression in animal explants, but not expression of noggin or follistatin; (6) mutant Xlim-1 elicited formation of partial secondary axes, and cooperated with gsc in notochord formation. Thus Xlim-1 has latent activities, implicating it in organizer functions.
C1 UNIV TOULOUSE 3,CNRS,UNITE MIXTE RECH 9925,CTR DEV BIOL,F-31062 TOULOUSE,FRANCE.
C3 Universite de Toulouse; Universite Toulouse III - Paul Sabatier; Centre National de la Recherche Scientifique (CNRS)
RP TAIRA, M (corresponding author), NICHHD,MOLEC GENET LAB,BETHESDA,MD 20892, USA.
NR 28
TC 183
Z9 195
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 677
EP 679
DI 10.1038/372677a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700086
PM 7990959
DA 2026-03-10
ER

PT J
AU BUTTERFIELD, NJ
AF BUTTERFIELD, NJ
TI BURGESS SHALE-TYPE FOSSILS FROM A LOWER CAMBRIAN SHALLOW-SHELF SEQUENCE IN NORTHWESTERN CANADA
SO NATURE
LA English
DT Article
ID wiwaxia-corrugata matthew; functional-morphology; adaptive radiation; crustacea; explosion; faunas
AB FOSSIL Lagerstatten comparable to that of the Burgess Shale potentially provide the detail necessary to resolve and assess the so-called Cambrian Explosion of multicellular life(1,2); distributional and taphonomic biases, however, often limit the generalizations that can be drawn. Here I report widespread occurrences of Burgess Shale-type fossils in shallow-shelf sediments of the Lower Cambrian Mount Cap Formation, District of Mackenzie, Northwest Territories, Canada. These borehole assemblages significantly expand the known geographical and ecological range of such fossil biotas and document the early appearance of both wiwaxiid polychaetes and filter-feeding crustaceans. The ability of this latter group to exploit microplanktic primary productivity marks a fundamental shift in trophic structuring and may distinguish Phanerozoic from pre-Phanerozoic ecosystems.
RP BUTTERFIELD, NJ (corresponding author), UNIV CAMBRIDGE,DEPT EARTH SCI,DOWNING ST,CAMBRIDGE CB2 3EQ,ENGLAND.
NR 30
TC 105
Z9 111
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 477
EP 479
DI 10.1038/369477a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600054
DA 2026-03-10
ER

PT J
AU RIDDIHOUGH, G
AF RIDDIHOUGH, G
TI FIRST-LINE DEFENSE
SO NATURE
LA English
DT Article
ID binding
AB Structural insight into the trimeric organization of the human mannose-binding protein sheds light on the workings of the non-clonal, innate immune response in vertebrates.
NR 5
TC 3
Z9 3
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 114
EP 114
DI 10.1038/372114a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800086
PM 7969405
DA 2026-03-10
ER

PT J
AU NODA, K
   GLOVER, BJ
   LINSTEAD, P
   MARTIN, C
AF NODA, K
   GLOVER, BJ
   LINSTEAD, P
   MARTIN, C
TI FLOWER COLOR INTENSITY DEPENDS ON SPECIALIZED CELL-SHAPE CONTROLLED BY A MYB-RELATED TRANSCRIPTION FACTOR
SO NATURE
LA English
DT Article
ID antirrhinum-majus; gene; homology; arabidopsis; expression; activator; patterns; proteins; products; locus
AB Flower colour is determined primarily by the production of pigments, usually anthocyanins or carotenoids, but the shade and intensity of the colour are often changed by other factors such as vacuolar compounds, pH and metal ions(1,2). Pigmentation can also be affected by the shape of epidermal cells, especially those facing prospective pollinators(3,4). A conical shape is believed to increase the proportion of incident light that enters the epidermal cells, enhancing light absorption by the floral pigments, and thus the intensity of their colour. We have identified a gene (mixta) that affects the intensity of pigmentation of epidermal cells in Antirrhinum majus petals. The cells of the corolla lobes fail to differentiate into their normal conical form in mixta mutants. We have cloned the mixta gene by transposon tagging; its sequence reveals that it encodes a Myb-related protein that probably participates in the transcriptional control of epidermal cell shape.
C1 JOHN INNES INST,NORWICH NR4 7UH,NORFOLK,ENGLAND.
C3 UK Research & Innovation (UKRI); Biotechnology and Biological Sciences Research Council (BBSRC); John Innes Centre
RP NODA, K (corresponding author), NIPPON OIL CO LTD,766 HIGASHI TOYOI,KUDAMATSU,YAMAGUCHI 744,JAPAN.
NR 21
TC 368
Z9 430
U1 6
U2 145
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 661
EP 664
DI 10.1038/369661a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900059
PM 8208293
DA 2026-03-10
ER

PT J
AU SCHMIDT, DL
   COBURN, CE
   DEKOVEN, BM
   POTTER, GE
   MEYERS, GF
   FISCHER, DA
AF SCHMIDT, DL
   COBURN, CE
   DEKOVEN, BM
   POTTER, GE
   MEYERS, GF
   FISCHER, DA
TI WATER-BASED NONSTICK HYDROPHOBIC COATINGS
SO NATURE
LA English
DT Article
ID contact angles; adsorption; surface
AB THERE is a considerable demand for materials that have surfaces to which other substances mill not easily stick. Coatings with these properties might be used to make surfaces non-adhesive towards soil, ice, biological foulants, graffiti and other unwanted contaminants. Here we describe a class of water-based non-stick Coatings prepared by self-assembly and immobilization of reactive polymeric surfactants(1,2). These polymer surfactants contain pendant perfluoroalkyl groups which become oriented so as to yield surfaces with very low energy. Immobilization by crosslinking increases non-stick performance and film toughness. These hard, clear coatings release adhesives and cannot bk wetted or attacked by solvents.
C1 DOW CHEM CO USA,CENT RES & DEV,MAT SCI & DEV LAB,MIDLAND,MI 48667.
   DOW CHEM CO USA,ANALYT SCI,MICHIGAN RES & DEV,MIDLAND,MI 48667.
   NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899.
C3 Dow Chemical Company; Dow Chemical Company; National Institute of Standards & Technology (NIST) - USA
RP SCHMIDT, DL (corresponding author), DOW CHEM CO USA,CENT RES & DEV,ADV POLYMER SYST LAB,1712 BLDG,MIDLAND,MI 48674, USA.
NR 26
TC 236
Z9 260
U1 1
U2 80
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 39
EP 41
DI 10.1038/368039a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900045
DA 2026-03-10
ER

PT J
AU HANNON, GJ
   BEACH, D
AF HANNON, GJ
   BEACH, D
TI P15(INK4B) IS A POTENTIAL EFFECTOR OF TGF-BETA-INDUCED CELL-CYCLE ARREST
SO NATURE
LA English
DT Article
ID transforming growth-factor; homozygous deletions; inhibition; kinases; line; melanoma
AB TRANSFORMING growth factor-beta (TGF-beta) inhibits cell proliferation by inducing a G1-phase cell cycle arrest(1). Normal progression through G1 is promoted by the activity of the cyclin-dependent protein kinases CDK4 and CDK6 (ref. 2), which are inhibited by the protein p16(INK4). We have isolated a new member of the p16(INK4) family, p15(INK4B). p15 expression is induced similar to 30-fold in human keratinocytes by treatment with TGF-beta, suggesting that p15 may act as an effector of TGF-beta-mediated cell cycle arrest. The gene encoding p15 is located on chromosome 9 adjacent to the p16 gene at a frequent site of chromosomal abnormality in human tumours (9p21).
C1 COLD SPRING HARBOR LAB,HOWARD HUGHES MED INST,COLD SPRING HARBOR,NY 11724.
C3 Cold Spring Harbor Laboratory; Howard Hughes Medical Institute
NR 28
TC 1963
Z9 2224
U1 1
U2 42
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 257
EP 261
DI 10.1038/371257a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000056
PM 8078588
DA 2026-03-10
ER

PT J
AU DUNLOP, JS
   HUGHES, DH
   RAWLINGS, S
   EALES, SA
   WARD, MJ
AF DUNLOP, JS
   HUGHES, DH
   RAWLINGS, S
   EALES, SA
   WARD, MJ
TI DETECTION OF A LARGE MASS OF DUST IN A RADIO GALAXY AT REDSHIFT Z=3.8
SO NATURE
LA English
DT Article
ID primeval galaxy; hidden quasar; quiet quasars; submillimeter; protogalaxy; luminosity; telescope; grains
AB Elliptical galaxies are thought to have formed most of their stars in a rapid burst in the early Universe(1), but an unambiguous example of a 'primaeval' elliptical galaxy (one undergoing its first major burst of star formation) has yet to be discovered. High-redshift radio galaxies are among the most promising candidates(2,3), because their low-redshift counterparts are identified exclusively with ellipticals, but the presence of an active nucleus complicates the analysis of their evolutionary state from optical-infrared observations(3-5). The failure of optical searches to detect primaeval ellipticals(6-9) suggests that they may be very dusty, prompting us to search for thermal emission from the dust, which will be redshifted to submillimetre wavelengths in our reference frame. Our detection of submillimetre emission from the radio galaxy 4C41.17, reported here, suggests that it contains a large mass of dust, probably located in a dust lane obscuring the centre of the galaxy(10-14). The observations are consistent with the recent occurrence of a massive burst of star formation, but probably not the first such episode. We conclude that this galaxy was already in the final stages of its formation at a look-back time of 12-15 billion years.
C1 UNIV OXFORD,DEPT ASTROPHYS,NUCL & ASTROPHYS LAB,OXFORD OX1 3RH,ENGLAND.
   UNIV TORONTO,DEPT ASTRON,TORONTO M5S 1A7,ON,CANADA.
C3 University of Oxford; University of Toronto
RP DUNLOP, JS (corresponding author), LIVERPOOL JOHN MOORES UNIV,SCH CHEM & PHYS SCI,BYROM ST,LIVERPOOL L3 3AF,MERSEYSIDE,ENGLAND.
NR 28
TC 119
Z9 120
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 347
EP 349
DI 10.1038/370347a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400047
DA 2026-03-10
ER

PT J
AU KEHLENBACH, RH
   MATTHEY, J
   HUTTNER, WB
AF KEHLENBACH, RH
   MATTHEY, J
   HUTTNER, WB
TI XL-ALPHA-S IS A NEW-TYPE OF G-PROTEIN
SO NATURE
LA English
DT Article
ID constitutive secretory vesicles; synaptic-like microvesicles; trans-golgi network; gtp-binding; receptor; membrane; mutations; endosm; subunits; p100
AB THE GTP-binding proteins are well-known regulators of cellular functions(1-4), including vesicular transport(5-7). Cholera toxin, which is known to catalyse ADP-ribosylation of the as subunit of heterotrimeric G proteins, stimulates secretory vesicle formation from the trans-Golgi network(8). Here we describe a new cholera toxin target, an 'extra large' G protein (XLas; M(r) 92K) which consists of a new 51K XL-portion linked to a Gas truncated at the amino terminus. XLas is specifically associated with the trans-Golgi network and occurs selectively in cells containing both the regulated and the constitutive pathway of protein secretion. Hence, XLas may mediate the effects of cholera toxin on secretory vesicle formation.
C1 UNIV HEIDELBERG, INST NEUROBIOL, D-69120 HEIDELBERG, GERMANY.
C3 Ruprecht Karls University Heidelberg
NR 35
TC 191
Z9 204
U1 0
U2 5
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 804
EP 809
DI 
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200060
PM 7997272
DA 2026-03-10
ER

PT J
AU FRANKE, EK
   YUAN, HEH
   LUBAN, J
AF FRANKE, EK
   YUAN, HEH
   LUBAN, J
TI SPECIFIC INCORPORATION OF CYCLOPHILIN-A INTO HIV-1 VIRIONS
SO NATURE
LA English
DT Article
ID human-immunodeficiency-virus; cyclosporine-a; gag; calcineurin; inhibition; expression; sequence; binding; cells; rna
AB LITTLE is known about host factors necessary for retroviral virion assembly or uncoating. We have previously shown that the principal structural protein of the human immunodeficiency virus HIV-1, the Gag polyprotein, binds the cyclophilin peptidyl-prolyl isomerases(1); cyclophilins catalyse a rate-limiting step in protein folding(2) and protect cells from heat shock(3). Here we demonstrate that cyclophilin A is specifically incorporated into HIV-1 virions but not into virions of other primate immunodeficiency viruses. A proline-rich region conserved in all HIV-1 Gag polyproteins is required for cyclophilin A binding and incorporation. Disruption of a single proline blocks the Gag-cyclophilin interaction in vitro, prevents cyclophilin A incorporation into virions, and inhibits HIV-1 replication. Our results indicate that the interaction of Gag with cyclophilin A is necessary for the formation of infectious HIV-1 virions.
RP FRANKE, EK (corresponding author), COLUMBIA UNIV,COLL PHYS & SURG,DEPT MED,701 W 168TH ST,NEW YORK,NY 10032, USA.
NR 26
TC 643
Z9 789
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 359
EP 362
DI 10.1038/372359a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700055
PM 7969494
DA 2026-03-10
ER

PT J
AU OETTGEN, HC
   MARTIN, TR
   WYNSHAWBORIS, A
   DENG, CX
   DRAZEN, JM
   LEDER, P
AF OETTGEN, HC
   MARTIN, TR
   WYNSHAWBORIS, A
   DENG, CX
   DRAZEN, JM
   LEDER, P
TI ACTIVE ANAPHYLAXIS IN IGE-DEFICIENT MICE
SO NATURE
LA English
DT Article
ID pertussigen pertussis toxin; immunoglobulin heavy-chain; mast-cells; cutaneous anaphylaxis; histamine-release; mouse; lymphocytes; lethality; mutation; antigen
AB The IgE-triggered release of mast cell mediators in response to antigen is thought to be the primary event in immediate hypersensitivity reactions such as systemic anaphylaxis(1). Although mast cells and basophils can be activated in vitro by non-IgE stimuli(2-5), it is not known whether these triggers lead to physiological changes in vivo. To investigate this possibility, we generated mice with a homozygous null mutation of the CE gene. Such mice make no IgE, but produce other immunoglobulin isotypes normally. We report that despite the IgE deficiency, sensitized mutant mice become anaphylactic on antigen challenge and display tachycardia and pulmonary function changes similar to those seen in wildtype animals. These responses are accompanied by vascular leak, sharply elevated plasma histamine and rapid death. IgE-independent anaphylaxis does not depend on complement activation, but, as indicated in studies using genetically immunodeficient RAG-2(-) and SCID mice, does require a functional immune system. Such results clearly demonstrate that non-IgE pathways for hypersensitivity reactions exist in mice.
C1 CHILDRENS HOSP,DEPT PEDIAT,INA SUE PERLMUTTER LAB,BOSTON,MA 02215.
   BRIGHAM & WOMENS HOSP,DEPT MED,BOSTON,MA 02115.
C3 Harvard University; Harvard University Medical Affiliates; Boston Children's Hospital; Harvard University; Harvard University Medical Affiliates; Brigham & Women's Hospital
RP OETTGEN, HC (corresponding author), HARVARD UNIV,SCH MED,HOWARD HUGHES MED INST,DEPT GENET,200 LONGWOOD AVE,BOSTON,MA 02115, USA.
NR 30
TC 354
Z9 385
U1 1
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 367
EP 370
DI 10.1038/370367a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400054
PM 8047141
DA 2026-03-10
ER

PT J
AU OBRIEN, T
   HARDIN, S
   GREENLEAF, A
   LIS, JT
AF OBRIEN, T
   HARDIN, S
   GREENLEAF, A
   LIS, JT
TI PHOSPHORYLATION OF RNA-POLYMERASE-II C-TERMINAL DOMAIN AND TRANSCRIPTIONAL ELONGATION
SO NATURE
LA English
DT Article
ID tata-binding protein; drosophila-melanogaster; largest subunit; heat-shock; nonphosphorylated form; in-vivo; 5' end; genes; initiation; complex
AB THE carboxy-terminal domain (CTD) of the large subunit of RNA polymerase II is essential in vivo(1-4), and is found in either an unphosphorylated (IIa) or hyperphosphorylated (IIo) form(5,6). The Drosophila uninduced hsp70 and hsp26 genes, and the constitutively expressed beta-1 tubulin and Gapdh-2 genes, contain an RNA polymerase II complex which pauses after synthesizing a short transcript(7-10). We report here that, using an in vivo ultraviolet crosslinking technique(11) and antibodies directed against the IIa and IIo forms of the CTD12, these paused polymerases have an unphosphorylated CTD. For genes containing a 5' paused polymerase, passage of the paused RNA polymerase into an elongationally competent mode in vivo coincides with phosphorylation of the CTD. Also, the level of phosphorylation of the CTD of elongating polymerases is shown not to be related to the level of transcription, but is promoter specific.
C1 CORNELL UNIV,BIOCHEM MOLEC & CELL BIOL SECT,ITHACA,NY 14853.
   DUKE UNIV,MED CTR,DEPT BIOCHEM,DURHAM,NC 27710.
C3 Cornell University; Duke University
NR 24
TC 301
Z9 339
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 75
EP 77
DI 10.1038/370075a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100063
PM 8015613
DA 2026-03-10
ER

PT J
AU HARRIS, DE
   CARILLI, CL
   PERLEY, RA
AF HARRIS, DE
   CARILLI, CL
   PERLEY, RA
TI X-RAY-EMISSION FROM THE RADIO HOTSPOTS OF CYGNUS-A
SO NATURE
LA English
DT Article
ID self-compton process; spherical geometry; galaxy
AB THE giant elliptical galaxy Cygnus A is regarded as the archetypal high-luminosity radio galaxy. These objects contain radio jets: an unknown energy source in the galactic nucleus generates two collimated outflows in opposite directions, which create radio hotspots where they interact with the surrounding intergalactic medium. Many radio galaxies are known to emit X-rays; in some cases these have been shown to come from the central core region, and in others from an extended galactic halo. Here we report the detection of X-ray emission from the hotspots of Cygnus A, obtained with the High Resolution Imager of the Rosat satellite. We show that an explanation based on thermal bremsstrahlung from a hot gas is inconsistent with radio polarization data and that a synchrotron model would require a population of relativistic electrons distinct from that responsible for the radio emission. Inverse Compton scattering of radio photons by relativistic electrons in the hotspots is, however, able to account for the observed X-ray intensity. A model based on this latter mechanism allows us to calculate the average magnetic field strength and the energy content of the relativistic electrons in the hotspots.
C1 STERREWACHT LEIDEN,2300 RA LEIDEN,NETHERLANDS.
   NATL RADIO ASTRON OBSERV,SOCORRO,NM 87801.
C3 Leiden University - Excl LUMC; Leiden University; National Radio Astronomy Observatory (NRAO)
RP HARRIS, DE (corresponding author), CTR ASTROPHYS,60 GARDEN ST,CAMBRIDGE,MA 02138, USA.
NR 12
TC 145
Z9 146
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 713
EP 716
DI 10.1038/367713a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100050
DA 2026-03-10
ER

PT J
AU BALICEGORDON, RJ
   LICHTMAN, JW
AF BALICEGORDON, RJ
   LICHTMAN, JW
TI LONG-TERM SYNAPSE LESS INDUCED BY FOCAL BLOCKADE OF POSTSYNAPTIC RECEPTORS
SO NATURE
LA English
DT Article
ID developing neuromuscular-junctions; acetylcholine-receptor; invivo visualization; nerve-terminals; skeletal-muscle; rat muscle; elimination; mouse; innervation; protein
AB Focal application in vivo of alpha-bungarotoxin to block neurotransmission in a small region of a neuromuscular junction causes long-lasting synapse elimination at that site. In contrast, blockade of neurotransmission throughout a junction does not cause synapse elimination. These and related experiments indicate that active synaptic sites can destabilize inactive synapses in their vicinity.
C1 WASHINGTON UNIV,SCH MED,DEPT ANAT & NEUROBIOL,ST LOUIS,MO 63110.
C3 Washington University (WUSTL)
NR 49
TC 234
Z9 268
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 519
EP 524
DI 10.1038/372519a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200043
PM 7990923
DA 2026-03-10
ER

PT J
AU BRAM, RJ
   CRABTREE, GR
AF BRAM, RJ
   CRABTREE, GR
TI CALCIUM SIGNALING IN T-CELLS STIMULATED BY A CYCLOPHILIN B-BINDING PROTEIN
SO NATURE
LA English
DT Article
ID cyclosporine-a; antigen receptor; tyrosine kinase; lymphocytes-t; activation; calcineurin; identification; transduction; expression; prediction
AB THE immunosuppressant drug cyclosporin A blocks a calcium-dependent signal from the T-cell receptor (TCR) that normally leads to T-cell activation(1-3). When bound to cyclophilin, cyclosporin A binds and inactivates the key signalling intermediate calcineurin(4-6). To identify potential cellular homologues of cyclosporin A that might regulate calcium signalling, we have cloned human genes encoding cyclophilin B-binding-proteins using the yeast two-hybrid system(7,8). One gene product, when overexpressed in Jurkat T cells, specifically induced transcription from the interleukin-2 enhancer, by activating the T-cell-specific transcription factors NF-AT and NF-IL2A. This protein, termed calcium-signal modulating cyclophilin ligand (CAML), acts downstream of the TCR and upstream of calcineurin by causing an influx of calcium. CAML appears to be a new participant in the calcium-signal transduction pathway, implicating cyclophilin B in calcium signalling, even in the absence of cyclosporin.
C1 ST JUDE CHILDRENS RES HOSP, DEPT HEMATOL ONCOL, MEMPHIS, TN 38105 USA.
   UNIV TENNESSEE, DEPT PEDIAT, MEMPHIS, TN 38105 USA.
   STANFORD UNIV, HOWARD HUGHES MED INST, STANFORD, CA 94305 USA.
   STANFORD UNIV, DEPT PATHOL, STANFORD, CA 94305 USA.
C3 St Jude Children's Research Hospital; University of Tennessee System; University of Tennessee Health Science Center; Howard Hughes Medical Institute; Stanford University; Stanford University
RP BRAM, RJ (corresponding author), ST JUDE CHILDRENS RES HOSP, DEPT EXPTL ONCOL, 332 N LAUDERDALE ST, MEMPHIS, TN 38105 USA.
NR 30
TC 149
Z9 172
U1 1
U2 3
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 355
EP 358
DI 10.1038/371355a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400059
PM 7522304
DA 2026-03-10
ER

PT J
AU MASUDA, S
   KOSUGI, T
   HARA, H
   OGAWARA, Y
AF MASUDA, S
   KOSUGI, T
   HARA, H
   OGAWARA, Y
TI A LOOP TOP HARD X-RAY SOURCE IN A COMPACT SOLAR-FLARE AS EVIDENCE FOR MAGNETIC RECONNECTION
SO NATURE
LA English
DT Article
ID a mission; telescope
AB SOLAR flares are thought to be the result of magnetic reconnection-the merging of antiparallel magnetic fields and the consequent release of magnetic energy, Flares are classified into two types(1): compact and two-ribbon. The two-ribbon flares, which appear as slowly-developing, long-lived large loops, are understood theoretically(2-6) as arising from an eruption of a solar prominence that pulls magnetic field lines upward into the corona. As the field lines form an inverted Y-shaped structure and relax, the reconnection of the field lines takes place. This view has been supported by recent observations(7-10). A different mechanism seemed to be required, however, to produce the short-lived, impulsive compact flares. Here we report observations made with the Yohkoh(11) Hard X-ray Telescope(12) and Soft X-ray Telescope(13), which show a compact flare with a geometry similar to that of a two-ribbon Bare. We identify the reconnection region as the site of particle acceleration, suggesting that the basic physics of the reconnection process (which remains uncertain) mag be common to both types of flare.
C1 NATL ASTRON OBSERV,MITAKA,TOKYO 181,JAPAN.
   UNIV TOKYO,INST ASTRON,MITAKA,TOKYO 181,JAPAN.
   INST SPACE & ASTRONAUT SCI,SAGAMIHARA,KANAGAWA 229,JAPAN.
C3 National Institutes of Natural Sciences (NINS) - Japan; National Astronomical Observatory of Japan (NAOJ); University of Tokyo; Japan Aerospace Exploration Agency (JAXA); Institute of Space & Astronautical Science (ISAS)
NR 22
TC 1022
Z9 1096
U1 1
U2 49
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 495
EP 497
DI 10.1038/371495a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900048
DA 2026-03-10
ER

PT J
AU STERN, TA
   HOLT, WE
AF STERN, TA
   HOLT, WE
TI PLATFORM SUBSIDENCE BEHIND AN ACTIVE SUBDUCTION ZONE
SO NATURE
LA English
DT Article
ID new-zealand; continental-margin; foreland basin; taranaki basin; flexure; lithosphere; evolution
AB NUMERICAL models of viscous mantle flow indicate that a broad subsidence should occur above subduction zones(1-4). This 'platform subsidence' is predicted to cause an asymmetrical depression 500-1,000 km wide, with a maximum depth of similar to 2 km if filled with water. Direct evidence linking platform subsidence to mantle flow has remained elusive, however. Here we offer evidence from western New Zealand for a complete link in both space and time between subduction initiation and platform subsidence. Because of the broad wavelength (>200 km) of the observed 1,500-m subsidence it is unlikely that the subsidence is due to a flexural foredeep. The observed subsidence does, however, match in both wavelength and amplitude that predicted by a model of subduction-induced mantle flow. The occurrence of platform subsidence has implications not only for understanding mantle convection, but also for explaining geoid anomalies over active margins(5) and patterns of continental submergence(6) and sedimentation(7) that could otherwise be interpreted as a eustatic sea level change(8).
C1 SUNY STONY BROOK,DEPT EARTH & SPACE SCI,STONY BROOK,NY 11794.
C3 State University of New York (SUNY) System; Stony Brook University
RP STERN, TA (corresponding author), VICTORIA UNIV WELLINGTON,RES SCH EARTH SCI,WELLINGTON,NEW ZEALAND.
NR 27
TC 48
Z9 53
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 233
EP 236
DI 10.1038/368233a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000052
DA 2026-03-10
ER

PT J
AU SADEGHNASSERI, S
   STERN, LJ
   WILEY, DC
   GERMAIN, RN
AF SADEGHNASSERI, S
   STERN, LJ
   WILEY, DC
   GERMAIN, RN
TI MHC CLASS-II FUNCTION PRESERVED BY LOW-AFFINITY PEPTIDE INTERACTIONS PRECEDING STABLE BINDING
SO NATURE
LA English
DT Article
ID antigenic peptide; invariant-chain; histocompatibility molecules; mice lacking; hla-dr; expression; complexes; hla-dr1
AB MAJOR histocompatibility complex class II molecules and their peptide ligands show unusual interaction kinetics, with slow association and dissociation rates that yield an apparent equilibrium constant of similar to 10(-6)-10(-8) M (refs 1-5). However, there is evidence for a specific, rapidly formed, short-lived complex(6). The altered migration on SDS-polyacrylamide gel electrophoresis of class II molecules upon stable peptide binding(7-9) has led to the hypothesis that the two kinetically distinguishable types of class II-peptide complexes correspond to different structures. In accord with this model, we demonstrate here that insert cell-derived HLA-DR1 class II molecules show fast, almost stoichiometric occupancy with rapidly dissociating peptide while remaining sensitive to SDS-induced chain dissociation. The same DR1 molecules slowly and quantitatively form long-lived complexes resistant to SDS-induced denaturation. Surprisingly, low-affinity interaction with peptide protects class II from denaturation at physiological temperature, a finding that has implications for understanding the role of invariant chain in the intracellular behaviour of class II molecules.
C1 NIAID,IMMUNOL LAB,LYMPHOCYTE BIOL SECT,BETHESDA,MD 20892.
   HARVARD UNIV,DEPT BIOCHEM & MOLEC BIOL,CAMBRIDGE,MA 02138.
   HARVARD UNIV,HOWARD HUGHES MED INST,CAMBRIDGE,MA 02138.
C3 National Institutes of Health (NIH) - USA; NIH National Institute of Allergy & Infectious Diseases (NIAID); Harvard University; Harvard University; Howard Hughes Medical Institute
NR 22
TC 133
Z9 142
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 647
EP 650
DI 10.1038/370647a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000049
PM 8065450
DA 2026-03-10
ER

PT J
AU OUBRIDGE, C
   ITO, N
   EVANS, PR
   TEO, CH
   NAGAI, K
AF OUBRIDGE, C
   ITO, N
   EVANS, PR
   TEO, CH
   NAGAI, K
TI CRYSTAL-STRUCTURE AT 1.92 ANGSTROM RESOLUTION OF THE RNA-BINDING DOMAIN OF THE U1A SPLICEOSOMAL PROTEIN COMPLEXED WITH AN RNA HAIRPIN
SO NATURE
LA English
DT Article
ID small nuclear ribonucleoprotein; x-ray-diffraction; hnrnp-c-proteins; a-protein; premessenger rna; synthetase; snrna; recognition; polyadenylation; crystallography
AB The crystal structure of the RNA-binding domain of the small nuclear ribonucleoprotein U1A bound to a 21-nucleotide RNA hairpin has been determined at 1.92 Angstrom resolution. The ten-nucleotide RNA loop binds to the surface of the beta-sheet as an open structure, and the AUUGCAC sequence of the loop interacts extensively with the conserved RNP1 and RNP2 motifs and the C-terminal extension of the RNP domain. These interactions include stacking of RNA bases with aromatic side chains of proteins and many direct and water-mediated hydrogen bonds. The structure reveals the stereochemical basis for sequence-specific RNA recognition by the RNP domain.
RP OUBRIDGE, C (corresponding author), MRC,MOLEC BIOL LAB,HILLS RD,CAMBRIDGE CB2 2QH,ENGLAND.
NR 50
TC 823
Z9 932
U1 1
U2 41
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 432
EP 438
DI 10.1038/372432a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200047
PM 7984237
DA 2026-03-10
ER

PT J
AU ARAKI, E
   LIPES, MA
   PATTI, ME
   BRUNING, JC
   HAAG, B
   JOHNSON, RS
   KAHN, CR
AF ARAKI, E
   LIPES, MA
   PATTI, ME
   BRUNING, JC
   HAAG, B
   JOHNSON, RS
   KAHN, CR
TI ALTERNATIVE PATHWAY OF INSULIN SIGNALING IN MICE WITH TARGETED DISRUPTION OF THE IRS-1 GENE
SO NATURE
LA English
DT Article
ID growth factor-i; stimulates tyrosine phosphorylation; receptor substrate-1; phosphatidylinositol 3-kinase; hematopoietic-cells; signaling pathways; protein; muscle; transmission; expression
AB THE principal substrate for the insulin and insulin-like growth factor-1 (IGF-1) receptors is the cytoplasmic protein insulin-receptor substrate-1 (IRS-1/pp185)(1-7). After tyrosine phosphorylation at several sites, IRS-1 binds to and activates phosphatidylinositol-3'-OH kinase (PI(3)K)(8-11) and several other proteins containing SH2 (Src-homology 2) domains(12-14). To elucidate the role of IRS-1 in insulin/IGF-1 action, we created IRS-1-deficient mice by targeted gene mutation. These mice had no IRS-1 and shelved no evidence IRS-1 phosphorylation or IRS-1-associated PI(3)K activity. They also had a 50 per cent reduction in intrauterine growth, impaired glucose tolerance, and a decrease in insulin/IGF-1-stimulated glucose uptake in vivo and in vitro. The residual insulin/ IGF-1 action correlated with the appearance of a new tyrosine-phosphorylated protein (IRS-2) which binds to PI(3)K, but is slightly larger than and immunologically distinct from IRS-1. Our results provide evidence for IRS-1-dependent and IRS-1-independent pathways of insulin/IGF-1 signalling and for the existence of an alternative substrate of these receptor kinases.
C1 JOSLIN DIABET CTR,DIV RES,BOSTON,MA 02215.
   HARVARD UNIV,SCH MED,DEPT MED,BOSTON,MA 02215.
C3 Harvard University; Harvard University Medical Affiliates; Joslin Diabetes Center, Inc.; Harvard University; Harvard Medical School
NR 31
TC 1077
Z9 1216
U1 0
U2 47
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 186
EP 190
DI 10.1038/372186a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800058
PM 7526222
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI MORE THAN JUST A FILM SET
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 804
EP 804
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700038
DA 2026-03-10
ER

PT J
AU GILLESPIE, DH
   CUDDY, KK
   KOLBE, T
   MARKS, DI
AF GILLESPIE, DH
   CUDDY, KK
   KOLBE, T
   MARKS, DI
TI DISSOLVE AND CAPTURE - A STRATEGY FOR ANALYZING MESSENGER-RNA IN BLOOD
SO NATURE
LA English
DT Article
ID thiocyanate; dna
C1 RNA LAB INC,EAGLE,PA 19480.
RP GILLESPIE, DH (corresponding author), HAHNEMANN UNIV,DEPT NEOPLAST DIS,ROAD & VINE,PHILADELPHIA,PA 19102, USA.
NR 9
TC 9
Z9 9
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 390
EP 391
DI 10.1038/367390a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000075
PM 7509457
DA 2026-03-10
ER

PT J
AU SCHACHTMAN, DP
   SCHROEDER, JI
AF SCHACHTMAN, DP
   SCHROEDER, JI
TI STRUCTURE AND TRANSPORT MECHANISM OF A HIGH-AFFINITY POTASSIUM UPTAKE TRANSPORTER FROM HIGHER-PLANTS
SO NATURE
LA English
DT Article
ID arabidopsis-thaliana; salt tolerance; barley roots; k+ channels; expression; membrane; cdna
AB POTASSIUM is the most abundant cation in higher plants and is crucial for plant nutrition, growth, tropisms, enzyme homeostasis and osmoregulation(1-4). K+ accumulation can be rate-limiting for agricultural production(2-4). K+ uptake from soils into roots is largely mediated by high-affinity K+ uptake (K-m approximate to 10-40 mu M) (refs 1, 2, 5-7). But although K+ channels allow low-affinity K+ uptake(8-10), both the transport mechanism and structure of the high-affinity K+ nutrition pathway remain unknown. Here we use expression cloning to isolate a complementary DNA encoding a membrane protein (HKT1) from wheat roots which confers the ability to take up K+. The substrate affinity, saturation and cation selectivity of HKT1 correspond to hallmark properties of classical high-affinity K+ uptake in plants(1,2,11). The transport mechanism of HKT1 uses K+-H+ co-uptake. Expression of HKT1 is localized to specific root and leaf regions which represent primary sites for K+ uptake in plants(2,3). HKT1 is important for plant nutrition and could possibly contribute to environmental alkali metal toxicities(11-13).
C1 UNIV CALIF SAN DIEGO, DEPT BIOL, LA JOLLA, CA 92093 USA.
   UNIV CALIF SAN DIEGO, CTR MOLEC GENET, LA JOLLA, CA 92093 USA.
C3 University of California System; University of California San Diego; University of California System; University of California San Diego
NR 30
TC 503
Z9 597
U1 6
U2 155
PU NATURE RESEARCH
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 655
EP 658
DI 10.1038/370655a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000052
PM 8065452
DA 2026-03-10
ER

PT J
AU STINE, S
AF STINE, S
TI EXTREME AND PERSISTENT DROUGHT IN CALIFORNIA AND PATAGONIA DURING MEDIEVAL TIME
SO NATURE
LA English
DT Article
ID lake; climate; record
AB STUDIES from sites around the world(1-5) have provided evidence for anomalous climate conditions persisting for several hundred years before about AD 1300. Early workers emphasized the temperature increase that marked this period in the British Isles, coining the terms 'Mediaeval Warm Epoch' and 'Little Climatic Optimum', but many sites seem to have experienced equally important hydrological changes. Here I present a study of relict tree stumps rooted in present-day lakes, marshes and streams, which suggests that California's Sierra Nevada experienced extremely severe drought conditions for more than two centuries before AD similar to 1112 and for more than 140 years before AD similar to 1350. During these periods, runoff from the Sierra was significantly lower than during any of the persistent droughts that have occurred in the region over the past 140 years. I also present similar evidence from Patagonia of drought conditions coinciding with at least the first of these dry periods in California. I suggest that the droughts may have been caused by reorientation of the mid-latitude storm tracks, owing to a general contraction of the circumpolar vortices and/or a change in the position of the vortex waves. If this reorientation was caused by mediaeval warming, future natural or anthropogenically induced warming may cause a recurrence of the extreme drought conditions.
RP STINE, S (corresponding author), CALIF STATE UNIV HAYWARD,DEPT GEOG & ENVIRONM STUDIES,HAYWARD,CA 94542, USA.
NR 12
TC 597
Z9 748
U1 2
U2 95
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 546
EP 549
DI 10.1038/369546a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400044
DA 2026-03-10
ER

PT J
AU ZANDBERGEN, HW
   JANSEN, J
   CAVA, RJ
   KRAJEWSKI, JJ
   PECK, WF
AF ZANDBERGEN, HW
   JANSEN, J
   CAVA, RJ
   KRAJEWSKI, JJ
   PECK, WF
TI STRUCTURE OF THE 13-K SUPERCONDUCTOR LA3NI2B2N3 AND THE RELATED PHASE LANIBN
SO NATURE
LA English
DT Article
AB THE recent discovery of superconductivity in a number of alloys containing boron and carbon has revived interest in the field of intermetallic superconductors(1-3). Although two structural forms have now been identified(4-6), most of the new intermetallic superconductors have a crystal structure typified by that of the quaternary alloy LuNi2B2C, in which layers of rock-salt-structured LuC alternate with nickel boride tetrahedra(4,5). The range of superconducting intermetallic compounds was extended recently by the discovery of superconductivity in a system of quaternary boro-nitride alloys, La-Ni-B-N (ref. 7). Here we report the structure of the superconducting phase in this system, La3Ni2B2N3, together with that of the related non-superconducting phase, LaNiBN. We find that these two phases are members of a homologous series (LaN)(n)(Ni2B2), with n = 3 and n = 2, respectively. Furthermore, our samples contain planar defects that suggest the existence of phases with larger n. Varying the number, n, of LaN layers within this system might thus provide a way to investigate the effect of dimensionality on the superconducting properties of intermetallics.
C1 UNIV AMSTERDAM,CRYSTALLOG LAB,1018 WV AMSTERDAM,NETHERLANDS.
   AT&T BELL LABS,MURRAY HILL,NJ 07974.
C3 University of Amsterdam; Nokia Corporation; Nokia Bell Labs; AT&T
RP ZANDBERGEN, HW (corresponding author), DELFT UNIV TECHNOL,NATL CTR HIGH RESOLUT ELECTRON MICROSCOPY,MAT SCI LAB,ROTTERDAMSEWEG 137,2628 AL DELFT,NETHERLANDS.
NR 9
TC 73
Z9 74
U1 0
U2 24
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 759
EP 761
DI 10.1038/372759a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200046
DA 2026-03-10
ER

PT J
AU PLEY, HW
   FLAHERTY, KM
   MCKAY, DB
AF PLEY, HW
   FLAHERTY, KM
   MCKAY, DB
TI MODEL FOR AN RNA TERTIARY INTERACTION FRONT THE STRUCTURE OF AN INTERMOLECULAR COMPLEX BETWEEN A GAAA TETRALOOP AND AN RNA HELIX
SO NATURE
LA English
DT Article
ID architecture; sequence; loops
AB IN large structured RNAs, RNA hairpins in which the strands of the duplex stem are connected by a tetraloop of the consensus sequence 5'-GNRA (where N is any nucleotide, and R is either G or A) are unusually frequent(1). In group I introns there is a covariation in sequence between nucleotides in the third and fourth positions of the loop with specific distant base pairs in putative RNA duplex stems(2): GNAA loops correlate with successive 5'-C-C.G-G base pairs in stems, whereas GNGA loops correlate with 5'-C-U.G-A. This has led to the suggestion that GNRA tetraloops may be involved in specific long-range tertiary interactions, with each A in position 3 or 4 of the loop interacting with a C-G base pair in the duplex, and G in position 3 interacting with a U-A base pair. This idea is supported experimentally for the GAAA loop of the P5b extension of the group I intron of Tetrahymena thermophila(3) and the L9 GUGA terminal loop of the td intron of bacteriophage T4 (ref. 4). NMR has revealed the overall structure of the tetraloop for 12-nucleotide hairpins with GCAA and GAAA loops(5) and models have been proposed for the interaction of GNRA tetraloops with base pairs in the minor groove of A-form RNA(2,4). Here we describe the crystal structure of an intermolecular complex between a GAAA tetraloop and an RNA helix. The interactions we observe correlate with tbe specificity of GNRA tetraloops inferred from phylogenetic studies, suggesting that this complex is a legitimate model for intramolecular tertiary interactions mediated by GNRA tetraloops in large structured RNAs.
C1 STANFORD UNIV,SCH MED,DEPT BIOL STRUCT,BECKMAN LABS STRUCT BIOL,STANFORD,CA 94305.
C3 Stanford University
NR 6
TC 269
Z9 302
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 111
EP 113
DI 10.1038/372111a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800085
PM 7526219
DA 2026-03-10
ER

PT J
AU MINOR, DL
   KIM, PS
AF MINOR, DL
   KIM, PS
TI CONTEXT IS A MAJOR DETERMINANT OF BETA-SHEET PROPENSITY
SO NATURE
LA English
DT Article
ID helix-forming tendency; streptococcal protein-g; occurring amino-acids; stability; parameters; alanine; glycine; peptide; water
AB RESIDUES in B-sheets occur in two distinct tertiary contexts: central strands, bordered on both sides by other beta-strands, and edge strands, bordered on only a single side by another beta-strand(1). The Delta Delta G values for beta-sheet formation measured at an edge beta-strand of the IgG-binding domain of protein G(GB1) are suite different from those obtained previously(2,3) at a central position in the same protein. In particular, there is no correlation at the edge position with statistically determined beta-sheet-forming preferences(4). The differences between beta-sheet propensities measured at central and edge beta-strands, Delta Delta Delta G values, correlate with the values of water/octanol transfer free energies(5) and side-chain non-polar surface area for the amino acids(6). These results strongly suggest that, unlike alpha-helix formation, beta-sheet formation is determined in large part by tertiary context, even at solvent-accessible sites, and not by intrinsic secondary structure preferences.
C1 MIT,WHITEHEAD INST BIOMED RES,HOWARD HUGHES MED INST,DEPT BIOL,CAMBRIDGE,MA.
C3 Massachusetts Institute of Technology (MIT); Whitehead Institute; Howard Hughes Medical Institute
RP MINOR, DL (corresponding author), MIT,WHITEHEAD INST BIOMED RES,HOWARD HUGHES MED INST,DEPT CHEM,9 CAMBRIDGE CTR,CAMBRIDGE,MA 02142, USA.
NR 29
TC 325
Z9 372
U1 1
U2 38
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 264
EP 267
DI 10.1038/371264a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000058
PM 8078589
DA 2026-03-10
ER

PT J
AU PRICE, M
   SUPPE, J
AF PRICE, M
   SUPPE, J
TI MEAN AGE OF RIFTING AND VOLCANISM ON VENUS DEDUCED FROM IMPACT CRATER DENSITIES
SO NATURE
LA English
DT Article
ID magellan observations; global distribution; atla-regio; features
AB UNLIKE the extensively cratered highlands of the Moon and Mars, the surface of Venus does not preserve a record of heavy bombardment from the early history of the Solar System(1-3). Those craters that are found on Venus appear to be statistically indistinguishable from a random spatial population and rarely show modification by folds, faults and lava flows(1-3). Although the volcanic and tectonic history of Venus is still much debated(2-5), there is mounting evidence for near-global resurfacing similar to 300-500 Myr ago(1,2,6). Moreover, it has recently been noted that the density of impact craters on large volcanic structures is less than the average crater density of the planet, suggestive of significant activity after the resurfacing event(7). It is not clear, however, whether these features represent late remnants of the global event or continuing volcanism and tectonism of a still active planet. To address this question, we have used the regional variations in crater density to date volcanoes, rifts and coronae which, based an stratigraphic evidence, clearly post-date the main resurfacing event(8-11). The calculated mean ages of 70-125 Myr exclude the possibility that the majority of these features represent the final stages of the global event.
RP PRICE, M (corresponding author), PRINCETON UNIV,DEPT GEOL & GEOPHYS SCI,PRINCETON,NJ 08544, USA.
NR 21
TC 75
Z9 78
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 756
EP 759
DI 10.1038/372756a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200045
DA 2026-03-10
ER

PT J
AU GREGOIRE, M
   MATTIELLI, N
   NICOLLET, C
   COTTIN, JY
   LEYRIT, H
   WEIS, D
   SHIMIZU, N
   GIRET, A
AF GREGOIRE, M
   MATTIELLI, N
   NICOLLET, C
   COTTIN, JY
   LEYRIT, H
   WEIS, D
   SHIMIZU, N
   GIRET, A
TI OCEANIC MAFIC GRANULITE XENOLITHS FROM THE KERGUELEN ARCHIPELAGO
SO NATURE
LA English
DT Article
ID south indian-ocean; crustal structure; ortho-pyroxene; plateau; garnet; evolution; islands; basalt; plume; ridge
AB OCEANIC plateaus are large accumulations of volcanic and plutonic rocks on the ocean floor, whose detailed nature and origin are only poorly understood. Their immense volumes, frequent occurrence since the Cretaceous period1 and conspicuous presence in all major ocean basins point to their significance in understanding the Earth's thermal and chemical evolution. We report here the discovery of mafic granulite xenoliths from Kerguelen island, at the northern end of the Kerguelen plateau-one of the two largest oceanic plateaus. Granulites are normally found only in continental settings, where the crust is thick enough to experience the high temperatures and pressures required for granulite-facies minerals to form. We speculate that the Kerguelen xenoliths represent basaltic magmas underplated during the evolution of the plateau, and more generally that such mafic granulites are an important constituent of the lower parts of oceanic plateaus, which are inaccessible by drilling.
C1 UNIV LIBRE BRUXELLES, PETROL & GEODYNAM CHIM LAB, B-1050 BRUSSELS, BELGIUM.
   UNIV CLERMONT FERRAND, CNRS, UA10, F-63038 CLERMONT FERRAND, FRANCE.
   INST GEOL ALBERT DE LAPPORENT, F-95000 CERGY, FRANCE.
   WOODS HOLE OCEANOG INST, DEPT GEOL & GEOPHYS, WOODS HOLE, MA 02543 USA.
C3 Universite Libre de Bruxelles; Centre National de la Recherche Scientifique (CNRS); Universite Clermont Auvergne (UCA); Woods Hole Oceanographic Institution
RP GREGOIRE, M (corresponding author), UNIV JEAN MONNET, GEOL LAB, CNRS, UA10, 23 RUE DOCTEUR PAUL MICHELON, F-42023 ST ETIENNE 02, FRANCE.
NR 41
TC 52
Z9 57
U1 0
U2 10
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 360
EP 363
DI 10.1038/367360a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000064
DA 2026-03-10
ER

PT J
AU HAGE, R
   IBURG, JE
   KERSCHNER, J
   KOEK, JH
   LEMPERS, ELM
   MARTENS, RJ
   RACHERLA, US
   RUSSELL, SW
   SWARTHOFF, T
   VANVLIET, MRP
   WARNAAR, JB
   VANDERWOLF, L
   KRIJNEN, B
AF HAGE, R
   IBURG, JE
   KERSCHNER, J
   KOEK, JH
   LEMPERS, ELM
   MARTENS, RJ
   RACHERLA, US
   RUSSELL, SW
   SWARTHOFF, T
   VANVLIET, MRP
   WARNAAR, JB
   VANDERWOLF, L
   KRIJNEN, B
TI EFFICIENT MANGANESE CATALYSTS FOR LOW-TEMPERATURE BLEACHING
SO NATURE
LA English
DT Article
ID crystal-structures; complexes; reactivity; model
AB The detergents of the next century will be routinely required to contain bleaching agents that are not only more active than those currently available but also environmentally safe and cost-effective. Hydrogen peroxide, the traditional bleaching agent(1), loses its activity as the washing temperature decreases. Peroxyacetic acid maintains acceptable bleaching activity down to 40-60 degrees C (ref. 2), but still lower temperatures are desirable. It if generally recognized that manganese and iron complexes are less environmentally damaging reagents than other transition-metal compounds, and such complexes have received considerable attention as bleaching catalysts(3-11). Here we show that manganese complexes derived from 1,4,7-trimethyl-1,4,7-triazacyclononane and related ligand systems act as highly effective catalysts for the bleaching of stains by hydrogen peroxide at low temperatures. These complexes also catalyse the epoxidation of alkenes and the oxidation of polyphenolic substrates by hydrogen peroxide. Our results demonstrate the considerable potential of these systems for clean and efficient low-temperature bleaching.
C1 UNILEVER RES US, EDGEWATER, NJ 07020 USA.
C3 Unilever
RP HAGE, R (corresponding author), UNILEVER RES LABS VLAARDINGEN, OLIVER VAN NOORTLAAN 120, 3133 AT VLAARDINGEN, NETHERLANDS.
NR 20
TC 314
Z9 426
U1 3
U2 52
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 637
EP 639
DI 10.1038/369637a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900051
DA 2026-03-10
ER

PT J
AU TAMEMOTO, H
   KADOWAKI, T
   TOBE, K
   YAGI, T
   SAKURA, H
   HAYAKAWA, T
   TERAUCHI, Y
   UEKI, K
   KABURAGI, Y
   SATOH, S
   SEKIHARA, H
   YOSHIOKA, S
   HORIKOSHI, H
   FURUTA, Y
   IKAWA, Y
   KASUGA, M
   YAZAKI, Y
   AIZAWA, S
AF TAMEMOTO, H
   KADOWAKI, T
   TOBE, K
   YAGI, T
   SAKURA, H
   HAYAKAWA, T
   TERAUCHI, Y
   UEKI, K
   KABURAGI, Y
   SATOH, S
   SEKIHARA, H
   YOSHIOKA, S
   HORIKOSHI, H
   FURUTA, Y
   IKAWA, Y
   KASUGA, M
   YAZAKI, Y
   AIZAWA, S
TI INSULIN-RESISTANCE AND GROWTH-RETARDATION IN MICE LACKING INSULIN-RECEPTOR SUBSTRATE-1
SO NATURE
LA English
DT Article
ID tyrosine-phosphorylation; rat adipocytes; phosphatidylinositol 3-kinase; hematopoietic-cells; signaling pathways; factor-i; protein; irs-1; kinase; association
AB INSULIN receptor substrate-1 (IRS-1) is the major substrate of insulin receptor and IGF-1 receptor tyrosine kinases; it has an apparent relative molecular mass of 160-190,000 (M(r), 160-190K) on SDS polyacrylamide gel(1-3). Tyrosine-phosphorylated IRS-1 binds the 85K subunit of phosphatidylinositol 3-kinase(4,5) which may be involved in the translocation of glucose transporters(6,7) and the abundant src homology protein (ASH)/Grb2(8,9) which may be involved in activation of p21(ras) and MAP kinase cascade(10). IRS-1 also has binding sites for Syp(11) and Nck(12) and other src homology 2 (SH2) signalling molecules. To clarify the physiological roles of IRS-1 in vivo, we made mice with a targeted disruption of the IRS-1 gene locus. Mice homozygous for targeted disruption of the IRS-1 gene were born alive but were retarded in embryonal and postnatal growth. They also had resistance to the glucose-lowering effects of insulin, IGF-1 and IGF-2. These data suggest the existence of both IRS-1-dependent and IRS-1-independent pathways for signal transduction of insulin and IGFs.
C1 UNIV TOKYO,FAC MED,DEPT INTERNAL MED 3,BUNKYO KU,TOKYO 113,JAPAN.
   INST PHYS & CHEM RES,TSUKUBA LIFE SCI CTR,ONCOL MOLEC LAB,TSUKUBA,IBARAKI 305,JAPAN.
   SANKYO CO LTD,PHARMACOL & MOLEC BIOL RES LABS,SHINAGAWA KU,TOKYO 140,JAPAN.
   YOKOHAMA CITY UNIV,FAC MED,SCH MED,DEPT INTERNAL MED 3,YOKOHAMA,KANAGAWA 236,JAPAN.
   UNIV KOBE,FAC MED,DEPT INTERNAL MED 2,KOBE,HYOGO 650,JAPAN.
C3 University of Tokyo; RIKEN; Daiichi Sankyo Company Limited; Yokohama City University; Kobe University
NR 30
TC 873
Z9 1010
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 182
EP 186
DI 10.1038/372182a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800057
PM 7969452
DA 2026-03-10
ER

PT J
AU MATTHEWS, S
   BARLOW, P
   BOYD, J
   BARTON, G
   RUSSELL, R
   MILLS, H
   CUNNINGHAM, M
   MEYERS, N
   BURNS, N
   CLARK, N
   KINGSMAN, S
   KINGSMAN, A
   CAMPBELL, I
AF MATTHEWS, S
   BARLOW, P
   BOYD, J
   BARTON, G
   RUSSELL, R
   MILLS, H
   CUNNINGHAM, M
   MEYERS, N
   BURNS, N
   CLARK, N
   KINGSMAN, S
   KINGSMAN, A
   CAMPBELL, I
TI STRUCTURAL SIMILARITY BETWEEN THE P17 MATRIX PROTEIN OF HIV-1 AND INTERFERON-GAMMA
SO NATURE
LA English
DT Article
ID immunodeficiency-virus type-1; 3-dimensional structure; terminal region; assignment; c-13; interleukin-1-beta; spectroscopy; resonance; backbone; spectra
AB THE human immunodeficiency virus (HIV) matrix protein, p17, Forms the outer shell of the core of the virus, lining the inner surface of the viral membrane(1-4). The protein has several key functions. It orchestrates viral assembly via targeting signals that direct the gag precursor polyprotein, p55, to the host cell membrane(1,5-7) and it interacts with the transmembrane protein, gp41, to retain the env-encoded proteins in the virus(8). In addition, p17 contains a nuclear localization signal that directs the preintegration complex to the nucleus of infected cells(9). This permits the virus to infect productively non-dividing cells, a distinguishing feature of HIV and other lentiviruses. We have determined the solution structure of p17 by nuclear magnetic resonance (NMR) with a root-mean square deviation for the backbone of the well-defined regions of 0.9 Angstrom. It consists of four helices connected by short loops and an irregular, mixed beta-sheet which provides a positively charged surface for interaction with the inner layer of the membrane. The helical topology is unusual; the Brookhaven protein database contains only one similar structure, that of the immune modulator interferon-gamma.
C1 UNIV OXFORD, DEPT BIOCHEM, OXFORD OX1 3QU, ENGLAND.
   UNIV OXFORD, OXFORD CTR MOLEC SCI, OXFORD OX1 3QU, ENGLAND.
   UNIV OXFORD, MOLEC BIOPHYS LAB, OXFORD OX1 3QU, ENGLAND.
   BRITISH BIOTECHNOL LTD, OXFORD OX4 5LY, ENGLAND.
C3 University of Oxford; University of Oxford; University of Oxford
NR 28
TC 125
Z9 133
U1 0
U2 5
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 666
EP 668
DI 10.1038/370666a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000055
PM 8065455
DA 2026-03-10
ER

PT J
AU ASHWELL, GJ
   JACKSON, PD
   CROSSLAND, WA
AF ASHWELL, GJ
   JACKSON, PD
   CROSSLAND, WA
TI NONCENTROSYMMETRY AND 2ND-HARMONIC GENERATION IN Z-TYPE LANGMUIR-BLODGETT-FILMS
SO NATURE
LA English
DT Article
ID 2nd harmonic-generation; hemicyanine dye; multilayers
AB THE principal requirement for materials that exhibit second-harmonic generation-frequency-doubling of light-is that they have a non-centrosymmetric structure. For optically active organic materials, this can be achieved by the use of the Langmuir-Blodgett (LB) technique1,2: amphiphilic molecules comprising a hydrophilic head (the chromophore) and a hydrophobic tail are aligned at an air-water interface, and the resulting ordered monolayer is transferred to an appropriate solid substrate. For practical applications, the non-centrosymmetric structure of the individual monolayers needs to be maintained across many such layers, but this has been achieved previously for relatively few optically active molecules3-5. Most amphiphiles pack centrosymmetrically, with the layers adopting a head-to-head and tail-to-tail 'Y-type' structure6. To enforce a non-centrosymmetric structure, it becomes necessary to intersperse the optically active layers with another material7-12. Here we demonstrate an alternative strategy for achieving macroscopic non-centrosymmetric order in LB multilayers. We find that the addition of a second hydrophobic end-group to the hydrophilic chromophore reduces the tendency of the molecules to invert during deposition, and a head-to-tail 'Z-type' structure can be readily obtained for films containing more than 100 layers.
RP ASHWELL, GJ (corresponding author), CRANFIELD UNIV, CTR MOLEC ELECTR, ADV MAT GRP, CRANFIELD MK43 0AL, ENGLAND.
NR 19
TC 139
Z9 148
U1 1
U2 10
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 438
EP 440
DI 10.1038/368438a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000057
DA 2026-03-10
ER

PT J
AU JONES, A
   ROBERTS, DL
   SLINGO, A
AF JONES, A
   ROBERTS, DL
   SLINGO, A
TI A CLIMATE MODEL STUDY OF INDIRECT RADIATIVE FORCING BY ANTHROPOGENIC SULFATE AEROSOLS
SO NATURE
LA English
DT Article
ID clouds; pollution; albedo
AB ANTHROPOGENIC sulphate aerosols are believed to affect the radiation budget of the Earth in two ways. Through the direct effect they scatter solar radiation back to space, producing a radiative forcing whose global annual mean has been estimated to lie in the range -0.3 to -0.9 W m (-2) (refs 1-3). This is significant compared to the longwave forcing due to increases in anthropogenic trace gases since the beginning of the industrial era, estimated at +2 to +2.5 W m(-2) (ref. 4). Aerosols also have an indirect effect, altering the distribution and concentration of cloud condensation nuclei (CCN) and hence the number density and size distribution of cloud droplets, thus affecting the solar radiative characteristics of Clouds(5,6). This is harder to quantify than the direct effect, because it depends on complex and poorly understood interactions between aerosols, CCN and cloud properties. Here we use sulphate aerosol data derived from a three-dimensional chemical transport model(7) to estimate the indirect radiative forcing by low-level water clouds using a general circulation model. We estimate that the indirect aerosol effect at the top of the atmosphere is approximately -1.3 W m(-2) in the global annual mean. Although this value is subject to a high level of uncertainty, even if the effect is only half as large it would still exceed many estimates of the direct effect, demonstrating its potential importance in climate change.
RP JONES, A (corresponding author), HADLEY CTR CLIMATE PREDICT & RES,METEOROL OFF,LONDON RD,BRACKNELL RG12 2SY,BERKS,ENGLAND.
NR 27
TC 300
Z9 323
U1 0
U2 70
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 450
EP 453
DI 10.1038/370450a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700053
DA 2026-03-10
ER

PT J
AU FREEMAN, WT
AF FREEMAN, WT
TI THE GENERIC VIEWPOINT ASSUMPTION IN A FRAMEWORK FOR VISUAL-PERCEPTION
SO NATURE
LA English
DT Article
ID regularization; vision
AB A VISUAL system makes assumptions in order to interpret visual data. The assumption of 'generic view'1-4 states that the observer is not in a special position relative to the scene. Researchers commonly use a binary decision of generic or accidental view to disqualify scene interpretations that assume accidental viewpoints5-10. Here we show how to use the generic view assumption, and others like it, to quantify the likelihood of a view, adding a new term to the probability of a given image interpretation. The resulting framework better models the visual world and reduces the reliance on other prior assumptions. It may lead to computer vision algorithms of greater power and accuracy, or to better models of human vision. We show applications to the problems of inferring shape, surface reflectance properties, and motion from images.
RP FREEMAN, WT (corresponding author), MITSUBISHI ELECT RES LABS, 201 BROADWAY, CAMBRIDGE, MA 02139 USA.
NR 24
TC 151
Z9 161
U1 0
U2 10
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 542
EP 545
DI 10.1038/368542a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500053
PM 8139687
DA 2026-03-10
ER

PT J
AU BRAUN, HA
   WISSING, H
   SCHAFER, K
   HIRSCH, MC
AF BRAUN, HA
   WISSING, H
   SCHAFER, K
   HIRSCH, MC
TI OSCILLATION AND NOISE DETERMINE SIGNAL-TRANSDUCTION IN SHARK MULTIMODAL SENSORY CELLS
SO NATURE
LA English
DT Article
ID neurons; transmission; information
AB OSCILLATING membrane potentials that generate rhythmic impulse patterns are considered to be of particular significance for neuronal information processing1-4. In contrast, noise is usually seen as a disturbance which limits the accuracy of information transfer5-8. We show here, however, that noise in combination with intrinsic oscillations can provide neurons with particular encoding properties, a discovery we made when recording from single electro-sensory afferents of a fish. The temporal sequence of the impulse trains indicates oscillations that operate near the spike-triggering threshold. The oscillation frequency determines the basic rhythm of impulse generation, but whether or not an impulse is actually triggered essentially depends on superimposed noise. The probability of impulse generation can be altered considerably by minor modifications of oscillation baseline and amplitude, which may underlie the exquisite sensitivity of these receptors to thermal and electrical stimuli. Additionally, thermal, but not electrical, stimuli alter the oscillation frequency, allowing dual sensory messages to be conveyed in a single spike train. These findings demonstrate novel properties of sensory transduction which may be relevant for neuronal signalling in general.
RP BRAUN, HA (corresponding author), UNIV MARBURG,INST PHYSIOL,DEUTSCHHAUSSTR 2,D-35037 MARBURG,GERMANY.
NR 30
TC 359
Z9 386
U1 0
U2 22
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 270
EP 273
DI 10.1038/367270a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400056
PM 11407413
DA 2026-03-10
ER

PT J
AU SCHNEIDER, HC
   BERTHOLD, J
   BAUER, MF
   DIETMEIER, K
   GUIARD, B
   BRUNNER, M
   NEUPERT, W
AF SCHNEIDER, HC
   BERTHOLD, J
   BAUER, MF
   DIETMEIER, K
   GUIARD, B
   BRUNNER, M
   NEUPERT, W
TI MITOCHONDRIAL HSP70/MIM44 COMPLEX FACILITATES PROTEIN IMPORT
SO NATURE
LA English
DT Article
ID translocation contact sites; yeast mitochondria; inner membrane; precursor proteins; intermembrane space; molecular chaperones; matrix; hsp70; pathway; binding
AB Protein translocation into mitochondria requires the mitochondrial protein Hsp70. This molecular chaperone of the mitochondrial matrix is recruited to the protein import machinery by MIM44, a component associated with the inner membrane of the mitochondria. Formation of the mt-Hsp70/MIM44 complex is regulated by ATP. MIM44 and mt-Hsp70 interact in a sequential manner with incoming segments of unfolded preproteins and thereby facilitate stepwise vectorial translocation of proteins across the mitochondrial membranes. The complex appears to act as a molecular ratchet which is energetically driven by the hydrolysis of ATP.
C1 UNIV MUNICH,INST PHYSIOL CHEM,D-80336 MUNICH,GERMANY.
C3 University of Munich
NR 51
TC 342
Z9 366
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 768
EP 774
DI 10.1038/371768a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800050
PM 7935837
DA 2026-03-10
ER

PT J
AU TULP, A
   VERWOERD, D
   DOBBERSTEIN, B
   PLOEGH, HL
   PIETERS, J
AF TULP, A
   VERWOERD, D
   DOBBERSTEIN, B
   PLOEGH, HL
   PIETERS, J
TI ISOLATION AND CHARACTERIZATION OF THE INTRACELLULAR MHC CLASS-II COMPARTMENT
SO NATURE
LA English
DT Article
ID hla-dr molecules; invariant chain; histocompatibility antigens; transferrin receptor; surface expression; fusion invitro; early endosome; cell line; transport; binding
AB An intracellular compartment has been isolated to which MHC class II molecules are transported on their way to the plasma membrane. They arrive with an associated invariant chain which is then proteolytically processed while MHC class II molecules acquire antigenic peptide. These loaded class II molecules then leave the compartment devoid of invariant chain and bound for the plasma membrane. This compartment represents a new stage in the endocytic/lysosomal pathway.
C1 NETHERLANDS CANC INST,DEPT IMMUNOL,1066 CX AMSTERDAM,NETHERLANDS.
   NETHERLANDS CANC INST,DEPT CELLULAR BIOCHEM,1066 CX AMSTERDAM,NETHERLANDS.
   UNIV HEIDELBERG,ZENTRUM MOLEK BIOL,W-6900 HEIDELBERG,GERMANY.
   MIT,CTR CANC RES,DEPT BIOL,CAMBRIDGE,MA 02139.
C3 Netherlands Cancer Institute; Netherlands Cancer Institute; Ruprecht Karls University Heidelberg; Massachusetts Institute of Technology (MIT)
NR 49
TC 410
Z9 426
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 120
EP 126
DI 10.1038/369120a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100040
PM 8177317
DA 2026-03-10
ER

PT J
AU VISWANATHAN, R
   ZASADZINSKI, JA
   SCHWARTZ, DK
AF VISWANATHAN, R
   ZASADZINSKI, JA
   SCHWARTZ, DK
TI SPONTANEOUS CHIRAL-SYMMETRY BREAKING BY ACHIRAL MOLECULES IN A LANGMUIR-BLODGETT-FILM
SO NATURE
LA English
DT Article
ID atomic force microscopy; air-water-interface; monolayers; spectroscopy
AB THE spontaneous breaking of symmetry is responsible for many physical phenomena, including the mass differences of elementary particles and phase transitions in condensed-matter systems. The breaking of mirror symmetry leads to chirality. In general, chiral effects in condensed-matter systems, such as optical activity, are associated with chiral molecular structures. But several recent observations1-3 of domain formation in thin organic films of achiral molecules have suggested that spontaneous separation into regions of differing chirality may occur in these systems. Eckhardt et al.4, meanwhile, have reported the spontaneous resolution of chiral molecules in Langmuir-Blodgett (LB) films. Here we present images of LB films of calcium arachidate obtained with the atomic force microscope5, which suggest that these achiral molecules can separate spontaneously into lattices with chiral packing of opposite handedness. We suggest that this symmetry breaking is driven by the interplay between the packing constraints imposed by the alkane tails and the molecular-area requirements set by the calcium ions6-13.
C1 UNIV CALIF SANTA BARBARA,DEPT CHEM ENGN,SANTA BARBARA,CA 93106.
   UNIV CALIF LOS ANGELES,DEPT CHEM,LOS ANGELES,CA 90024.
C3 University of California System; University of California Santa Barbara; University of California System; University of California Los Angeles
NR 30
TC 148
Z9 158
U1 1
U2 56
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 440
EP 443
DI 10.1038/368440a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000058
DA 2026-03-10
ER

PT J
AU GUILLEMOT, F
   NAGY, A
   AUERBACH, A
   ROSSANT, J
   JOYNER, AL
AF GUILLEMOT, F
   NAGY, A
   AUERBACH, A
   ROSSANT, J
   JOYNER, AL
TI ESSENTIAL ROLE OF MASH-2 IN EXTRAEMBRYONIC DEVELOPMENT
SO NATURE
LA English
DT Article
ID embryonic stem-cells; scute gene-complex; nervous-system; mouse
AB THE outer layer of the blastocyst, or trophectoderm, is the first cell lineage to differentiate in the mouse embryo(1,2), but little is known about the genetic control of its development. Lineage-specific transcription factors may be important in lineage specification, and the product of the Mash-2 gene(3,4) fulfils the criteria for such a factor. Mash-2 is a mammalian member of the achaete-scute family(5-7) which encodes basic-helix-loop-helix transcription factors(8) and is strongly expressed in the extraembryonic trophoblast lineage. Mash-2 transcripts are found in the female germ line and in the embryo throughout preimplantation development, but are highly expressed later only in the ectoplacental cone, the chorion and their derivatives in the placenta. Mash-2 transcripts are not found in primary and secondary giant cells, yolk sac or allantois at any post-implantation stage, and are present only transiently and at low levels in the embryo during gastrulation. To analyse the role of Mash-2 in development, we have used gene targeting to generate mice having no Mash-2 function. We report here that Mash-2(-1-) embryos die from placental failure at 10 days postcoitum. In mutant placentas, spongiotrophoblast cells and their precursors are absent and chorionic ectoderm is reduced. We have rescued this placental mutant phenotype by constructing chimaeras with tetraploid wild-type embryos which contribute almost exclusively to extraembryonic tissues(9,10). Mash-2(-1-) embryos developed normally and adult Mash-2(-1-) mice were viable, demonstrating that Mash-2 has no major role in the embryo itself. Mash-2 is the first transcription factor shown to play a critical part in the development of the mammalian trophoblast lineage.
C1 MT SINAI HOSP,SAMUEL LUNENFELD RES INST,TORONTO M5G 1X5,ON,CANADA.
   UNIV TORONTO,DEPT MOLEC & MED GENET,TORONTO M5S 1A8,ON,CANADA.
C3 University of Toronto; Sinai Health System Toronto; Lunenfeld Tanenbaum Research Institute; University of Toronto
NR 20
TC 520
Z9 583
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 333
EP 336
DI 10.1038/371333a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400052
PM 8090202
DA 2026-03-10
ER

PT J
AU DACEY, JWH
   DRAKE, BG
   KLUG, MJ
AF DACEY, JWH
   DRAKE, BG
   KLUG, MJ
TI STIMULATION OF METHANE EMISSION BY CARBON-DIOXIDE ENRICHMENT OF MARSH VEGETATION
SO NATURE
LA English
DT Article
ID elevated co2; estuarine marsh; rice paddy; community; productivity; responses; wetlands; plants; growth; field
AB THERE is substantial evidence that many plants respond to increased concentrations of atmospheric carbon dioxide by increasing their productivity(1-4) This observation has led to the suggestion that, by taking up CO2, the terrestrial biosphere might mitigate the potential greenhouse warming associated with anthropogenic CO2 emissions(5). Whiting and Chanton(6) have found, however, that for wetlands of varying productivity around the world, higher net primary production is associated with higher emissions of methane-another important greenhouse gas. Here we present measurements of methane emissions from a marsh that has been exposed to twice the present ambient concentration of atmospheric CO2. We find that over a one-week period, the CO2-enriched sites had significantly higher emissions of methane than the control sites. Our results suggest that future increases in atmospheric CO2 concentration may lead to significant increases in methane emissions from wetlands.
C1 SMITHSONIAN ENVIRONM RES CTR, EDGEWATER, MD 21037 USA.
   MICHIGAN STATE UNIV, KELLOGG BIOL STN, HICKORY CORNERS, MI 49060 USA.
C3 Smithsonian Institution; Smithsonian Environmental Research Center; Michigan State University
RP DACEY, JWH (corresponding author), WOODS HOLE OCEANOG INST, WOODS HOLE, MA 02543 USA.
NR 32
TC 109
Z9 122
U1 1
U2 104
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 47
EP 49
DI 10.1038/370047a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100053
DA 2026-03-10
ER

PT J
AU BISSELL, RA
   CORDOVA, E
   KAIFER, AE
   STODDART, JF
AF BISSELL, RA
   CORDOVA, E
   KAIFER, AE
   STODDART, JF
TI A CHEMICALLY AND ELECTROCHEMICALLY SWITCHABLE MOLECULAR SHUTTLE
SO NATURE
LA English
DT Article
ID alpha-cyclodextrin; rotaxane
AB The developing field of nanotechnology has generated wide interest across a broad range of scientific disciplines(1). In particular, the realization of nanoscale switching devices might have far-reaching implications for computing and biomimetic engineering(2-4). But miniaturization of existing semiconductor technology may not be the best approach to the fabrication of structures whose dimensions are smaller than the wavelength of the radiation used in optical lithography and etching techniques(5). The approach observed in the natural world, whereby nanostructures are built up through the self-assembly(6-9) of smaller molecular entities, holds substantial promise. Nature abounds with molecular switching devices which perform a variety of functions, such as the transport of metabolites across cell membranes or the signalling of nerve impulses. These processes are commonly controlled by stimuli such as changes in ion concentrations and electrical potentials. Here we report the synthesis of a supramolecular structure (compound 1.[PF6](4), Fig. 1A) that can be reversibly switched between two states by proton concentration changes or by electrochemical means. The supermolecule is a rotaxane comprising a molecular ring threaded on an axle containing two 'docking points'. We can effect controlled switching of the ring from one of these positions to the other. We use H-1 NMR and ultraviolet/visible spectroscopy to characterize the dynamics of the bead's movement along the thread before and after switching.
C1 UNIV MIAMI,DEPT CHEM,CORAL GABLES,FL 33124.
   UNIV BIRMINGHAM,SCH CHEM,BIRMINGHAM B15 2TT,ENGLAND.
C3 University of Miami; University of Birmingham
NR 32
TC 1131
Z9 1234
U1 7
U2 567
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 133
EP 137
DI 10.1038/369133a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100044
DA 2026-03-10
ER

PT J
AU LIN, M
   SEN, A
AF LIN, M
   SEN, A
TI DIRECT CATALYTIC CONVERSION OF METHANE TO ACETIC-ACID IN AN AQUEOUS-MEDIUM
SO NATURE
LA English
DT Article
ID carbonylation; oxidation; alkanes
AB ALTHOUGH methane is the most-abundant of alkanes, hazards of handling and distribution prevent known methane reserves1,2 from being fully exploited. Moreover, it is the least reactive alkane, so whereas selective conversion to more useful chemical products would be of great value, it is difficult to achieve. A useful target molecule for methane conversion is acetic acid, but existing approaches to this conversion on an industrial scale involve many steps under extreme reaction conditions3-5. Previous reports of the direct catalytic conversion of methane to acetic acid have involved peroxvdisulphate as the oxidant6,7, but any such process that could be adapted to large-scale applications would have to use O2 as the oxidant. Here we describe such a process, which uses rhodium trichloride as the catalyst, proceeds in an aqueous medium at a temperature of around 100-degrees-C, and gives high yields of acetic acid. This reaction provides a potentially useful means to convert methane directly to an industrially useful organic compound and greatly expands the scope of catalytic functionalization of alkanes.
RP SEN, A (corresponding author), PENN STATE UNIV,DEPT CHEM,UNIV PK,PA 16802, USA.
NR 15
TC 252
Z9 298
U1 3
U2 172
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 613
EP 615
DI 10.1038/368613a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200053
DA 2026-03-10
ER

PT J
AU SCHRADER, M
   MULLER, KM
   NAYERI, S
   KAHLEN, JP
   CARLBERG, C
AF SCHRADER, M
   MULLER, KM
   NAYERI, S
   KAHLEN, JP
   CARLBERG, C
TI VITAMIN-D-3 THYROID-HORMONE RECEPTOR HETERODIMER POLARITY DIRECTS LIGAND SENSITIVITY OF TRANSACTIVATION
SO NATURE
LA English
DT Article
ID retinoic acid receptors; signaling pathways; response elements; gene-expression; direct repeats; x-receptor; rxr; binding; rar; identification
AB The nuclear receptors for 1,25-dihydroxyvitamin D-3 (VD) and 3,5,3'-triiodothyronine (T-3), that is, VDRs and T(3)Rs respectively, control aspects of homeostasis, cell growth and differentiation(1-4). They activate transcription from response elements consisting of direct repeats, palindromes and inverted palindromes(5-8) of a variety of hexameric core-binding motifs. VDRs bind preferentially to direct repeats spaced by three nucleotides, whereas T(3)Rs bind to direct repeats spaced by four nucleotides(9). VDRs and T(3)Rs can function as homodimers(5,6,10) but heterodimerization with retinoid X(11-14) Or retinoic acid receptors(15,16) increases their affinity for DNA in vitro and resulting transcriptional activity in vivo. We recently observed the formation of VDR-T(3)R heterodimers(17). Here we show that the polarity of the binding of such heterodimers to the VD response element of the rat 9K (relative molecular mass 9,000) calbindin's gene promoter was 5'-T(3)R-VDR-3', whereas on the mouse 28K calbindin VD response element(19) this polarity was reversed to 5'-VDR-T(3)R-3'. We also show that the ligand for the downstream receptor controls the transcriptional activity of the heterodimeric complex. Thus, polarity seems to be an important regulatory property of heterodimeric nuclear receptor complexes.
RP SCHRADER, M (corresponding author), UNIV GENEVA,HOP CANTONAL,DERMATOL CLIN,CH-1211 GENEVA 14,SWITZERLAND.
NR 30
TC 128
Z9 137
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 382
EP 386
DI 10.1038/370382a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400059
PM 8047145
DA 2026-03-10
ER

PT J
AU ROMEO, G
   RONCHETTO, P
   LUO, Y
   BARONE, V
   SERI, M
   CECCHERINI, I
   PASINI, B
   BOCCIARDI, R
   LERONE, M
   KAARIAINEN, H
   MARTUCCIELLO, G
AF ROMEO, G
   RONCHETTO, P
   LUO, Y
   BARONE, V
   SERI, M
   CECCHERINI, I
   PASINI, B
   BOCCIARDI, R
   LERONE, M
   KAARIAINEN, H
   MARTUCCIELLO, G
TI POINT MUTATIONS AFFECTING THE TYROSINE KINASE DOMAIN OF THE RET PROTOONCOGENE IN HIRSCHPRUNGS DISEASE
SO NATURE
LA English
DT Article
ID activation; receptor
AB HIRSCHSPRUNG'S disease is a genetic disorder of neural crest development affecting 1 in 5,000 births. It is characterized by the absence of intramural ganglion cells in the hindgut, which often results in partial to complete intestinal obstruction during the first years of life. An autosomal dominant gene causing this disease was recently mapped to chromosome 10q11.2 (refs 1, 2), using an interstitial deletion of this region isolated in a cell hybrid3,4. It was subsequently localized to a 250-kilobase interval which contains the RET proto-oncogene5. Using flanking intronic sequences as primers6 to amplify 12 of the 20 exons of RET from genomic DNA of 27 Hirschsprung's disease patients, we have now identified four mutations (one frameshift and three missense) that totally disrupt or partially change the structure of the tyrosine kinase domain of the RET protein (Ret). Mutations in the extracellular cysteine-rich domain of Ret have been identified previously7,8 in patients with multiple endocrine neoplasia type 2A, and a targeted mutation in the tyrosine kinase domain of the same gene produces intestinal aganglionosis and kidney agenesis in homozygous transgenic mice9. Our results support the hypothesis that RET, in addition to its potential role in tumorigenesis, plays a critical role in the embryogenesis of the mammalian enteric nervous system.
C1 UNIV HELSINKI,DEPT MED GENET,SF-00014 HELSINKI,FINLAND.
C3 University of Helsinki
RP ROMEO, G (corresponding author), IST GIANNINA GASLINI,I-16148 GENOA,ITALY.
NR 25
TC 636
Z9 677
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 377
EP 378
DI 10.1038/367377a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000070
PM 8114938
DA 2026-03-10
ER

PT J
AU NOMOTO, K
   YAMAOKA, H
   VANDENHEUVEL, EPJ
   IWAMOTO, K
   KUMAGAI, S
   SHIGEYAMA, T
   POLS, OR
AF NOMOTO, K
   YAMAOKA, H
   VANDENHEUVEL, EPJ
   IWAMOTO, K
   KUMAGAI, S
   SHIGEYAMA, T
   POLS, OR
TI A CARBON-OXYGEN STAR AS PROGENITOR OF THE TYPE-IC SUPERNOVA 1994I
SO NATURE
LA English
DT Article
ID mass helium star; ib supernovae; evolution; models; binary; 1987m
AB SUPERNOVAE are classified observationally as type I (which have no hydrogen emission lines in their optical spectra) or type II (which do have hydrogen lines), and are further subdivided(1) into types Ia, Ib, Ic, IIP, IIL and IIb. Type II supernovae are generally thought to result from the explosion of massive stars, and type Ia supernovae from white-dwarf stars that have accreted sufficient mass from a companion to trigger explosion(1,2). The origins of types Ib and Ic are much less clear. The Ic class has been particularly controversial, with two main alternatives: the explosion of a massive star that has lost its hydrogen and helium envelopes through fast stellar winds, exposing the carbon- and oxygen-rich core; or the transfer of material to a companion, leaving a small, bare carbon-oxygen (C + O) star which subsequently explodes(3,4). We show here that the observed characteristics of SN1994I (in the nearby galaxy NGC5194), which has recently(5,6) been classified as type Ic, are best understood on the basis of the second of the two alternatives above: that the progenitor was in a close binary system and lost its outer envelopes, leaving a C + O star (of mass approximate to 2 solar masses) which exploded when its iron core collapsed.
C1 KYUSHU UNIV,FAC SCI,DEPT PHYS,FUKUOKA 810,JAPAN.
   UNIV CAMBRIDGE,INST ASTRON,CAMBRIDGE CB3 0HA,ENGLAND.
   UNIV AMSTERDAM,INST ASTRON,1018 WB AMSTERDAM,NETHERLANDS.
   UNIV AMSTERDAM,CTR HIGH ENERGY ASTROPHYS,AMSTERDAM,NETHERLANDS.
   INST PHYS & CHEM RES,WAKO,SAITAMA 35101,JAPAN.
C3 Kyushu University; University of Cambridge; University of Amsterdam; University of Amsterdam; RIKEN
RP NOMOTO, K (corresponding author), UNIV TOKYO,FAC SCI,DEPT ASTRON,TOKYO 113,JAPAN.
NR 30
TC 178
Z9 186
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 227
EP 229
DI 10.1038/371227a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000044
DA 2026-03-10
ER

PT J
AU DAVIES, K
AF DAVIES, K
TI ALLERGY BY MUTATION
SO NATURE
LA English
DT Article
ID chromosome-11q
AB The search for genetic factors that may predispose people to various allergies takes a promising turn with the publication of some incriminating evidence against the IgE receptor.
NR 8
TC 1
Z9 4
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 506
EP 506
DI 10.1038/369506a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600063
DA 2026-03-10
ER

PT J
AU ANTONUCCI, R
   HURT, T
   KINNEY, A
AF ANTONUCCI, R
   HURT, T
   KINNEY, A
TI EVIDENCE FOR A QUASAR IN THE RADIO GALAXY CYGNUS-A FROM OBSERVATION OF BROAD-LINE EMISSION
SO NATURE
LA English
DT Article
ID high-redshift; spectropolarimetry; continuum; ngc-1068; nucleus; spectrum
AB ACTIVE galaxies are thought to be powered by the accretion of surrounding dust and gas onto central black holes. The unified model(1-3) of active galaxies predicts that narrow-line radio galaxies (NLRGs), which are very luminous at radio wavelengths and have narrow optical emission lines, would appear as quasars-which have broad emission lines-if viewed from a different direction. The nearby NLRG Cygnus A is the most luminous radio source in the local Universe, with a luminosity that lies within the range of that of quasars(4), but the polarization of optical light from this source seems at odds with the quasar model. Here we present evidence, in the form of broad ultraviolet line emission from singly ionized magnesium, that Cygnus A does indeed host a quasar.
C1 SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218.
C3 Space Telescope Science Institute
RP ANTONUCCI, R (corresponding author), UNIV CALIF SANTA BARBARA,DEPT PHYS,SANTA BARBARA,CA 93106, USA.
NR 39
TC 56
Z9 59
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 313
EP 314
DI 10.1038/371313a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400045
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI BIODIVERSITY - AN UNMAPPED RESOURCE
SO NATURE
LA English
DT Article
NR 1
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 801
EP 801
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700035
DA 2026-03-10
ER

PT J
AU AGLADZE, NI
   SIEVERS, AJ
   JONES, SA
   BURLITCH, JM
   BECKWITH, SVW
AF AGLADZE, NI
   SIEVERS, AJ
   JONES, SA
   BURLITCH, JM
   BECKWITH, SVW
TI REASSESSMENT OF MILLIMETER-WAVE ABSORPTION-COEFFICIENTS IN INTERSTELLAR SILICATE GRAINS
SO NATURE
LA English
DT Article
ID temperature; dust; masses
AB ALMOST all of the elements heavier than helium in the interstellar medium reside in small solid dust particles(1). Dust dominates the energy balance through its continuous absorption and emission of radiation. Its opacity provides the only direct means to assess the total mass in many interstellar regions: for example, in molecular clouds(2), in circumstellar disks undergoing planet formation(3-5) and even in some galaxies(6). But there are almost no laboratory measurements of small-particle opacities at low temperatures for any of the principal constituents of interstellar dust at the far-infrared and millimetre wavelengths at which most observations are made. Here we report a laboratory study of absorption by forsterite (Mg2SiO4), the pure magnesian form of the mineral olivine, which is a main constituent of interstellar dust We have measured millimetre-wave absorption spectra of synthesized amorphous and crystalline forsterite powders between 3.5 and 15 cm(-1) at temperatures below 30 K, the region most germane to estimates of interstellar dust mass. Our measurements indicate that the absorption per unit mass for this silicate is several times larger than that normally assumed in astronomical research(7-10). Estimates of the opacity of interstellar dust may have to be increased accordingly, causing the mass of interstellar particles derived from observations of the opacity to be lowered by a corresponding amount.
C1 CORNELL UNIV,CTR RADIOPHYS & SPACE RES,ITHACA,NY 14853.
   CORNELL UNIV,DEPT CHEM,ITHACA,NY 14853.
   MAX PLANCK INST ASTRON,D-69117 HEIDELBERG,GERMANY.
C3 Cornell University; Cornell University; Max Planck Society
RP AGLADZE, NI (corresponding author), CORNELL UNIV,ATOM & SOLID STATE PHYS LAB,ITHACA,NY 14853, USA.
NR 23
TC 43
Z9 44
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 243
EP 245
DI 10.1038/372243a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900042
DA 2026-03-10
ER

PT J
AU WAN, KT
   DAVIS, ME
AF WAN, KT
   DAVIS, ME
TI DESIGN AND SYNTHESIS OF A HETEROGENEOUS ASYMMETRIC CATALYST
SO NATURE
LA English
DT Article
ID supported aqueous-phase; rhodium hydroformylation catalysts; hydrogenation; binap; ruthenium; water
AB THE need for enantiomerically pure pharmaceuticals and insecticides drives the search for new catalysts that can perform asymmetric reactions with high enantiomeric selectivity. Many chiral transformations are accomplished using homogeneous catalysts(1). Recently we reported(2) a heterogeneous catalyst for asymmetric hydrogenation reactions, in which an organometallic catalytic complex is held in a film of water on a porous hydrophilic support, while the reactants and products remain within a hydrophobic organic phase. Such systems provide a large interfacial area between the catalytic phase and the solvent, and should facilitate the separation of product from catalyst. Our previous system(2) gave selectivities of only about 70% enantiomeric excess, however, whereas values of at least 95% are needed for practical utility. Here we describe a modified process in which an enantiomeric excess of 96% is obtained for the asymmetric reduction of 2-(6'-methoxy-2'-naphthyl)acrylic acid to the commercially important anti-inflammatory agent naproxen. We use ethylene glycol as the hydrophilic liquid phase containing the chiral catalyst, which effectively prevents the leaching of the complex into the organic phase. Our results show that these supported-phase asymmetric catalytic systems have the potential to become commercially viable.
RP WAN, KT (corresponding author), CALTECH, DIV CHEM & CHEM ENGN, PASADENA, CA 91125 USA.
NR 16
TC 189
Z9 208
U1 2
U2 92
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 449
EP 450
DI 10.1038/370449a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700052
DA 2026-03-10
ER

PT J
AU LEHMING, N
   THANOS, D
   BRICKMAN, JM
   MA, J
   MANIATIS, T
   PTASHNE, M
AF LEHMING, N
   THANOS, D
   BRICKMAN, JM
   MA, J
   MANIATIS, T
   PTASHNE, M
TI AN HMG-LIKE PROTEIN THAT CAN SWITCH A TRANSCRIPTIONAL ACTIVATOR TO A REPRESSOR
SO NATURE
LA English
DT Article
ID beta-interferon gene; dorsoventral pattern; dorsal morphogen; drosophila; enhancer; silencer; conversion; promoters; elements; cactus
AB ONE protein can activate some genes and repress others in the same cell(1). The Drosophila protein Dorsal(2) (which, like the human protein NF-kappa B-3, is a member of the Rel family of transcriptional activators) activates the twist gene and represses the zen gene in the ventral region of early embryos(4,5). Here we describe a Drosophila HMG1 protein, called DSP1 (dorsal switch protein), that converts Dorsal and NF-kappa B from transcriptional activators to repressors. This effect requires a sequence termed a negative regulatory element (NRE), found adjacent to Dorsal-binding sites in the zen promoter and adjacent to the NF-kappa B-binding site in the human interferon-beta (IFN-beta) enhancer(6-8). Previous studies have shown that another type of HMG protein, HMG I(Y), can stimulate NF-kappa B activity(9). Thus, the HMG-like proteins DSP1 and HMG I(Y) can determine whether a specific regulator functions as an activator or a repressor of transcription.
RP LEHMING, N (corresponding author), HARVARD UNIV,DEPT BIOCHEM & MOLEC BIOL,7 DIVIN AVE,CAMBRIDGE,MA 02138, USA.
NR 31
TC 209
Z9 222
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 175
EP 179
DI 10.1038/371175a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100069
PM 8072548
DA 2026-03-10
ER

PT J
AU PENNER, TL
   MOTSCHMANN, HR
   ARMSTRONG, NJ
   EZENYILIMBA, MC
   WILLIAMS, DJ
AF PENNER, TL
   MOTSCHMANN, HR
   ARMSTRONG, NJ
   EZENYILIMBA, MC
   WILLIAMS, DJ
TI EFFICIENT PHASE-MATCHED 2ND-HARMONIC GENERATION OF BLUE-LIGHT IN AN ORGANIC WAVE-GUIDE
SO NATURE
LA English
DT Article
ID wave-guide; films
AB THE development of materials for the efficient frequency-doubling of low-power semiconductor lasers is a technologically important goal for which several important challenges remain. The ease of processing and high intrinsic optical nonlinearity of organic materials1,2 makes them attractive for such applications, and it has been demonstrated that molecular-assembly techniques can achieve the macroscopic non-centrosymmetric order required for bulk nonlinear optical activity3,4.  But to achieve efficient power conversion, a promising material must also exhibit low attenuation of light at high power densities, and match phase velocities over relatively long distances for light at the fundamental and second-harmonic frequencies5. Here we report the fabrication by Langmuir-Blodgett deposition of a low-loss optical waveguide in which precise control of the film thickness, together with inversion of the nonlinear susceptibility across the film, are used to simultaneously achieve phase matching and improve the optical-field overlap between the propagating (fundamental and second-harmonic) waveguide modes. The resulting structure converts low-power near-infrared laser light efficiently to blue light.
RP PENNER, TL (corresponding author), EASTMAN KODAK CO,IMAGING RES & ADV DEV,ROCHESTER,NY 14650, USA.
NR 19
TC 99
Z9 100
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 49
EP 51
DI 10.1038/367049a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500053
DA 2026-03-10
ER

PT J
AU HOU, S
   HYLAND, L
   RYAN, KW
   PORTNER, A
   DOHERTY, PC
AF HOU, S
   HYLAND, L
   RYAN, KW
   PORTNER, A
   DOHERTY, PC
TI VIRUS-SPECIFIC CD8+ T-CELL MEMORY DETERMINED BY CLONAL BURST SIZE
SO NATURE
LA English
DT Article
ID lymphocytic choriomeningitis virus; sendai virus; invivo; mice; expression; influenza; infection; immunity; antigen; beta
AB Although some viruses, particularly the herpes viruses, may never be eliminated from the body(1), others like influenza A, regularly reinfect humans and boost waning crossreactive CD8(+) T-cell immunity(2). Prolonged T-cell memory is found for viruses that are unlikely to be re-encountered and which do not persist in the host genome(3-5), indicating that CD8(+) T-cell memory might be independent dent of continued (or sporadic) antigenic exposure. A feature of virus-specific CD8(+) T-cell memory is that antigen-specific cytotoxic T-lymphocyte precursors (CTLp) are greatly increased and remain high throughout life. The idea that persistence of the inducing antigen is essential is based on experiments in which adoptively transferred CD8(+) memory T cells could not be detected for more than a few weeks in naive recipient mice without secondary challenge(6,7). Here we show that restimulation of such chimaeric mice with an inducing Sendai virus antigen increases the clonal burst size more than 7-fold within 8 days, making memory CTLp easier to detect in the longer term. We find that Sendai-virus-specific CTLp are maintained for >250 days in irradiated uninfected recipients, including reconstituted beta(2)-microglobulin(-/-) mice. To determine whether a source of viral peptide can persist after primary infection, we gave Sendai-virus-specific Thy1.1(+) memory spleen cells to naive mice that had been minimally depleted of Thy1.2(+) T cells, or to comparable recipients that had recovered from infection with Sendai virus or influenza virus. Although antibody against Sendai virus was never found in the naive recipients, Sendai-virus-specific CD8(+) memory T cells were maintained equally well in each case for >100 days after cell transfer. We find so evidence for persisting depots of viral protein that might feed into the endogenous processing pathway and maintain virus-specific CD8(+) T-cell memory.
C1 ST JUDE CHILDRENS RES HOSP, DEPT VIROL & IMMUNOL, MEMPHIS, TN 38105 USA.
   ST JUDE CHILDRENS RES HOSP, DEPT MOLEC BIOL, MEMPHIS, TN 38105 USA.
C3 St Jude Children's Research Hospital; St Jude Children's Research Hospital
NR 28
TC 470
Z9 520
U1 0
U2 5
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 652
EP 654
DI 10.1038/369652a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900056
PM 7516039
DA 2026-03-10
ER

PT J
AU SONGAILA, A
   COWIE, LL
   HOGAN, CJ
   RUGERS, M
AF SONGAILA, A
   COWIE, LL
   HOGAN, CJ
   RUGERS, M
TI DEUTERIUM ABUNDANCE AND BACKGROUND-RADIATION TEMPERATURE IN HIGH-REDSHIFT PRIMORDIAL CLOUDS
SO NATURE
LA English
DT Article
ID absorption; evolution; spectrum; origin; limit; he-3; qsos; hot
AB Measurements of the deuterium abundance in the early Universe provide a sensitive test of the 'standard' Big Bang cosmology. The probable detection of deuterium absorption by a gas cloud between us and a distant quasar suggests an abundance much greater than estimated from observations in the Milky Way, and consistent with the amount of presently observed luminous matter comprising all the baryons in the Universe. The same spectra imply a cosmic background temperature for the early Universe which is consistent with our expectations from standard Big Bang cosmology.
C1 UNIV WASHINGTON, DEPT ASTRON, SEATTLE, WA 98195 USA.
C3 University of Washington; University of Washington Seattle
RP SONGAILA, A (corresponding author), UNIV HAWAII, INST ASTRON, 2680 WOODLAWN DR, HONOLULU, HI 96822 USA.
NR 33
TC 284
Z9 287
U1 0
U2 1
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 599
EP 604
DI 10.1038/368599a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200050
DA 2026-03-10
ER

PT J
AU WINFREE, AT
AF WINFREE, AT
TI PERSISTENT TANGLED VORTEX RINGS IN GENERIC EXCITABLE MEDIA
SO NATURE
LA English
DT Article
ID spiral waves; organizing centers; cellular automaton; chemical waves; model; excitation; equations; mechanism; dynamics
AB EXCITABLE media are exemplified by a range of living systems(1-8), such as mammalian heart muscle(6) and its cells(1) and Xenopus eggs(2,3). They also occur in non-living systems such as the autocatalytic Belousov-Zhabatinsky reactiong(9-14). In most of these systems, activity patterns, such as concentration waves, typically radiate as spiral waves from a vortex of excitation created by some nonuniform stimulus. In three-dimensional systems, the vortex is commonly a line, and these vortex lines can form linked and knotted rings which contract into compact, particle-like bundles(9-30). In most previous work these stable 'organizing centres' have been found to be symmetrical and can be classified topologically. Here I show through numerical studies of a generic excitable medium that the more general configuration of vortex lines is a turbulent tangle, which is robust against changes in the parameters of the system or perturbations to it. In view of their stability, I suggest that these turbulent tangles should be observable in any of the many known excitable media.
RP WINFREE, AT (corresponding author), UNIV ARIZONA, DEPT ECOL & EVOLUT BIOL, TUCSON, AZ 85721 USA.
NR 38
TC 59
Z9 61
U1 1
U2 15
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 233
EP 236
DI 10.1038/371233a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000047
PM 8078583
DA 2026-03-10
ER

PT J
AU KOKUBO, T
   GONG, DW
   WOOTTON, JC
   HORIKOSHI, M
   ROEDER, RG
   NAKATANI, Y
AF KOKUBO, T
   GONG, DW
   WOOTTON, JC
   HORIKOSHI, M
   ROEDER, RG
   NAKATANI, Y
TI MOLECULAR-CLONING OF DROSOPHILA TFIID SUBUNITS
SO NATURE
LA English
DT Article
ID major late promoter; rna polymerase-ii; tata box-binding; transcription factor; preinitiation complex; protein; nucleosome; coactivators; initiation
AB TRANSCRIPTION initiation factor TFIID is a multisubunit complex containing a TATA-box-binding factor (TFIIDtau/TBP) and associated polypeptide factors (TAFs) with sizes ranging from M(r) approximately 20,000 to >200,000 (refs 1-7). As a result of direct promoter interactions8,9, TFIID nucleates the assembly of RNA polymerase II and other initiation factors into a functional preinitiation complex10. Although the native TFIID complex mediates both basal and activator-dependent transcription in reconstituted systems, TBP itself is competent for only basal transcription. Thus, TAFs are essential cofactors for regulated transcription. The complementary DNAs encoding the p230 (M(r) 230,000), p110 and p85 subunits of TFIID have recently been cloned11-18. Here we report the molecular cloning and characterization of the p62, p42, p28 and p22 subunits. These participate in a network of heterogeneous protein-protein interactions within TFIID. Sequence similarities between p62/p42 and the histones H4/H3, respectively, suggest that these subunits have a functional relationship with chromatin.
C1 NICHHD,BETHESDA,MD 20892.
   NINCDS,BETHESDA,MD 20892.
   NATL CTR BIOTECHNOL INFORMAT,BETHESDA,MD 20892.
   ROCKEFELLER UNIV,BIOCHEM & MOLEC BIOL LAB,NEW YORK,NY 10021.
   UNIV TOKYO,INST MOLEC & CELLULAR BIOSCI,BUNKYO KU,TOKYO 113,JAPAN.
C3 National Institutes of Health (NIH) - USA; NIH Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD); National Institutes of Health (NIH) - USA; NIH National Institute of Neurological Disorders & Stroke (NINDS); Rockefeller University; University of Tokyo
NR 30
TC 105
Z9 113
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 484
EP 487
DI 10.1038/367484a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900061
PM 7545910
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI STATE-UNIVERSITIES - BUILDING BRIDGES
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 796
EP 797
DI 
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700029
DA 2026-03-10
ER

PT J
AU CORTIJO, E
   DUPLESSY, JC
   LABEYRIE, L
   LECLAIRE, H
   DUPRAT, J
   VANWEERING, TCE
AF CORTIJO, E
   DUPLESSY, JC
   LABEYRIE, L
   LECLAIRE, H
   DUPRAT, J
   VANWEERING, TCE
TI EEMIAN COOLING IN THE NORWEGIAN SEA AND NORTH-ATLANTIC OCEAN PRECEDING CONTINENTAL ICE-SHEET GROWTH
SO NATURE
LA English
DT Article
ID deep-water circulation; reconstruction; greenland; cycle; age
AB CHANGING conditions in the North Atlantic region may drive global climate changes(1,2). According to previous reconstructions of the last interglacial (the Eemian), North Atlantic sea surface temperatures (SSTs) were similar to present-day values(3). In the Norwegian Sea, even warmer conditions appeared as a single pulse of short duration(4,5), whereas the Greenland ice record suggests that the warm interglacial air temperatures were interrupted by several cold periods(6). Here we use faunal and stable-isotope analyses of foraminifera in two sediment cores from the North Atlantic ocean and Norwegian Sea to reconstruct high-resolution records of SST and sea surface salinity (SSS) during the Eemian interglacial. Our results, which differ significantly from the Greenland record(6), show a sharp decrease in SST and SSS of the Norwegian Sea, associated with a more moderate cooling and freshening of the North Atlantic at the middle of isotope substage 5e, several millennia before the beginning of continental ice-sheet growth. Changes in the Norwegian Sea surface conditions appear to have represented an important climate change affecting global atmospheric and thermohaline circulations.
C1 UNIV BORDEAUX 1, DEPT GEOL & OCEANOG, F-33405 TALENCE, FRANCE.
   NETHERLANDS INST SEA RES, 1790 AB DEN BURG, NETHERLANDS.
C3 Universite de Bordeaux; Utrecht University; Royal Netherlands Institute for Sea Research (NIOZ)
RP CORTIJO, E (corresponding author), CEA, CNRS, CTR FAIBLES RADIOACT, F-91198 GIF SUR YVETTE, FRANCE.
NR 31
TC 160
Z9 170
U1 0
U2 10
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 446
EP 449
DI 10.1038/372446a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200051
DA 2026-03-10
ER

PT J
AU ECK, MJ
   ATWELL, SK
   SHOELSON, SE
   HARRISON, SC
AF ECK, MJ
   ATWELL, SK
   SHOELSON, SE
   HARRISON, SC
TI STRUCTURE OF THE REGULATORY DOMAINS OF THE SRC-FAMILY TYROSINE KINASE LCK
SO NATURE
LA English
DT Article
ID protein structures; crystal-structure; sh3 domain; identification; p60c-src; binding
AB THE kinase p56(lck) (Lck) is a T-lymphocyte-specific member of the Src family of non-receptor tyrosine kinases(1). Members of the Src family each contain unique amino-terminal regions, followed by Src-homology domains SH3 and SH2, and a tyrosine kinase domain. SH3 and SH2 domains mediate critical protein interactions in many signal-transducing pathways(2). They are small, independently folded modules of about 60 and 100 residues, respectively, and they are often but not always found together in the same molecule. Like all nine Src-family kinases (reviewed in ref. 3), Lck is regulated by phosphorylation of a tyrosine in the short C-terminal tail of its catalytic domain(4). There is evidence that binding of the phosphorylated tail to the SH2 domain inhibits catalytic activity of the kinase domain(5,6) and that the SH3 and SH2 domains may act together to effect this regulation(7). Here we report the crystal structures for a fragment of Lck bearing its SH3 and SH2 domains, alone and in complex with a phosphotyrosyl peptide containing the sequence of the Lck C-terminal regulatory tail. The latter complex represents the regulatory apparatus of Lck. The SH3-SH2 fragment forms similar dimers in both crystals, and the tail peptide binds at the intermolecular SH3/SH2 contact. The two structures show how an SH3 domain might recognize a specific target and suggest how dimerization could play a role in regulating Src-family kinases.
C1 CHILDRENS HOSP MED CTR, MOLEC MED LAB, BOSTON, MA 02115 USA.
   HARVARD UNIV, SCH MED, DEPT MICROBIOL & MOLEC GENET, BOSTON, MA 02115 USA.
   HARVARD UNIV, BRIGHAM & WOMENS HOSP,SCH MED,JOSLIN DIABET CTR, DIV RES, BOSTON, MA 02115 USA.
   HARVARD UNIV, DEPT BIOCHEM & MOLEC BIOL, CAMBRIDGE, MA 02138 USA.
C3 Harvard University; Harvard University Medical Affiliates; Boston Children's Hospital; Harvard University; Harvard Medical School; Harvard University; Harvard University Medical Affiliates; Joslin Diabetes Center, Inc.; Harvard Medical School; Brigham & Women's Hospital; Harvard University
RP ECK, MJ (corresponding author), CHILDRENS HOSP MED CTR, HOWARD HUGHES MED INST, 300 LONGWOOD AVE, BOSTON, MA 02115 USA.
NR 30
TC 268
Z9 288
U1 0
U2 5
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 764
EP 769
DI 10.1038/368764a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300065
PM 7512222
DA 2026-03-10
ER

PT J
AU MIYOSHI, M
   MATSUMOTO, K
   KAMENO, S
   TAKABA, H
   IWATA, T
AF MIYOSHI, M
   MATSUMOTO, K
   KAMENO, S
   TAKABA, H
   IWATA, T
TI COLLISIONAL PUMPING OF SIO MASERS IN EVOLVED STARS
SO NATURE
LA English
DT Article
ID emission
AB ALTHOUGH SiO masers (lasing systems at microwave frequencies) have been detected in many old red-giant stars(1,2), several fundamental questions, such as what drives the masers and where in the stars' environment they are located(3), remain unresolved. Evolved stars are known to have winds, which distribute enriched material throughout the interstellar medium, but the acceleration mechanism and the point in the stellar atmosphere at which the winds are initiated, are unknown(4). SiO masers have high brightness temperatures, which allows them to be studied with high spatial and spectral resolution using very-long-baseline interferometry (VLBI) techniques, and thereby potentially determine how the stellar winds are generated. This will only be possible, however, once the physical conditions giving rise to the maser emission are known. Here we present images of positionally coincident maser emission from the J=1-->0 rotational transition of the first two vibrational levels in the SiO masers in VY Canis Majoris and W Hydrae. These results clearly demonstrate that the maser emission is collisionally pumped in distinct regions, rather than radiatively pumped. This means that SiO maser emission can be used to follow the clumps of gas as they are accelerated in the stellar atmosphere.
C1 UNIV ELECTROCOMMUN,CHOFU,TOKYO 182,JAPAN.
   NATL ASTRON OBSERV,NOBEYAMA RADIO OBSERV,MINAMISA KU,NAGANO 38413,JAPAN.
   COMMUN RES LABS,KASHIMA SPACE RES CTR,KASHIMA,IBARAKI 314,JAPAN.
C3 University of Electro-Communications - Japan; National Institutes of Natural Sciences (NINS) - Japan; National Astronomical Observatory of Japan (NAOJ); National Institute of Information & Communications Technology (NICT) - Japan
RP MIYOSHI, M (corresponding author), NATL ASTRON OBSERV,MIZUSAWA ASTROGEODYNAM OBSERV,2-11 2-12 HOSHIGAOKA,MIZUSAWA,IWATE 023,JAPAN.
NR 16
TC 81
Z9 85
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 395
EP 397
DI 10.1038/371395a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500034
DA 2026-03-10
ER

PT J
AU KING, GM
   SCHNELL, S
AF KING, GM
   SCHNELL, S
TI EFFECT OF INCREASING ATMOSPHERIC METHANE CONCENTRATION ON AMMONIUM INHIBITION OF SOIL METHANE CONSUMPTION
SO NATURE
LA English
DT Article
ID methylosinus-trichosporium; nitrous-oxide; forest soils; oxidation; bacteria; ch4
AB SOILS currently consume about 30-40 Tg methane per year(1,2), which is comparable to the net annual increase in atmospheric methane concentration from 1980 to 1990(3). Most soils consume methane(2,4-9), but the extent varies with soil water content, land use and ammonium inputs(5,10-13). Ammonium concentrations in many soils have increased in recent years as a result of land-use changes and increases in ammonium concentration in precipitation(14,15). Ammonium strongly inhibits soil methane consumption, but the mechanism is uncertain. Even if enhanced ammonium concentrations are subsequently reduced, inhibition can still persist for months to years(12,13). Here we show, from field and laboratory experiments, that the extent of ammonium inhibition increases with increasing methane concentration. We propose that nitrite formation from methanotrophic ammonium oxidation accounts for much of the observed inhibition, and that the persistence of inhibition with reduced ammonium concentrations is due to the limited capacity of methanotrophs to grow or recover in present concentrations of atmospheric methane. We suggest that past increases in atmospheric methane concentration may have increased the inhibitory effect of ammonium, thereby decreasing soil methane uptake capacity, and that this mechanism could also provide a positive feedback on future atmospheric methane concentrations.
RP KING, GM (corresponding author), UNIV MAINE, DARLING MARINE CTR, WALPOLE, ME 04573 USA.
NR 28
TC 191
Z9 233
U1 2
U2 74
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 282
EP 284
DI 10.1038/370282a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900059
DA 2026-03-10
ER

PT J
AU DUJON, B
   ALEXANDRAKI, D
   ANDRE, B
   ANSORGE, W
   BALADRON, V
   BALLESTA, JPG
   BANREVI, A
   BOLLE, PA
   BOLOTINFUKUHARA, M
   BOSSIER, P
   BOU, G
   BOYER, J
   BUITRAGO, MJ
   CHERET, G
   COLLEAUX, L
   DALGNANFORNIER, B
   DELREY, F
   DION, C
   DOMDEY, H
   DUSTERHOFT, A
   DUSTERHUS, S
   ENTLAN, KD
   ERFLE, H
   ESTEBAN, PF
   FELDMANN, H
   FERNANDES, L
   FOBO, GM
   FRITZ, C
   FUKUHARA, H
   GABEL, C
   GAILLON, L
   CARCIACANTALEJO, JM
   GARCIARAMIREZ, JJ
   GENT, ME
   GHAZVINI, M
   GOFFEAU, A
   GONZALEZ, A
   GROTHUES, D
   GUERREIRO, P
   HEGEMANN, J
   HEWITT, N
   HILGER, F
   HOLLENBERG, CP
   HORAITIS, O
   INDGE, KJ
   JACQUIER, A
   JAMES, CM
   JAUNIAUX, JC
   JIMENEZ, A
   KEUCHEL, H
   KIRCHRATH, L
   KLEINE, K
   KOTTER, P
   LEGRAIN, P
   LIEBL, S
   LOUIS, EJ
   SILVA, AME
   MARCK, C
   MONNIER, AL
   MOSTL, D
   MULLER, S
   OBERMAIER, B
   OLIVER, SG
   PALLIER, C
   PASCOLO, S
   PFEIFFER, F
   PHILIPPSEN, P
   PLANTA, RJ
   POHL, FM
   POHL, TM
   POHLMANN, R
   PORTETELLE, D
   PURNELLE, B
   PUZOS, V
   RAD, MR
   RASMUSSEN, SW
   REMACHA, M
   REVUELTA, JL
   RICHARD, GF
   RIEGER, M
   RODRIGUESPOUSADA, C
   ROSE, M
   RUPP, T
   SANTOS, MA
   SCHWAGER, C
   SENSEN, C
   SKALA, J
   SOARES, H
   SOR, F
   STEGEMANN, J
   TETTELIN, H
   THIERRY, A
   TZERMIA, M
   URRESTARAZU, LA
   VANDYCK, L
   VANVLIETREEDIJK, JC
   VALENS, M
   VANDENBOL, M
   VILELA, C
   VISSERS, S
   VON WETTSTEIN, D
   VOSS, H
   WIEMANN, S
   XU, G
   ZIMMERMANN, J
   HAASEMANN, M
   BECKER, I
   MEWES, HW
AF DUJON, B
   ALEXANDRAKI, D
   ANDRE, B
   ANSORGE, W
   BALADRON, V
   BALLESTA, JPG
   BANREVI, A
   BOLLE, PA
   BOLOTINFUKUHARA, M
   BOSSIER, P
   BOU, G
   BOYER, J
   BUITRAGO, MJ
   CHERET, G
   COLLEAUX, L
   DALGNANFORNIER, B
   DELREY, F
   DION, C
   DOMDEY, H
   DUSTERHOFT, A
   DUSTERHUS, S
   ENTLAN, KD
   ERFLE, H
   ESTEBAN, PF
   FELDMANN, H
   FERNANDES, L
   FOBO, GM
   FRITZ, C
   FUKUHARA, H
   GABEL, C
   GAILLON, L
   CARCIACANTALEJO, JM
   GARCIARAMIREZ, JJ
   GENT, ME
   GHAZVINI, M
   GOFFEAU, A
   GONZALEZ, A
   GROTHUES, D
   GUERREIRO, P
   HEGEMANN, J
   HEWITT, N
   HILGER, F
   HOLLENBERG, CP
   HORAITIS, O
   INDGE, KJ
   JACQUIER, A
   JAMES, CM
   JAUNIAUX, JC
   JIMENEZ, A
   KEUCHEL, H
   KIRCHRATH, L
   KLEINE, K
   KOTTER, P
   LEGRAIN, P
   LIEBL, S
   LOUIS, EJ
   SILVA, AME
   MARCK, C
   MONNIER, AL
   MOSTL, D
   MULLER, S
   OBERMAIER, B
   OLIVER, SG
   PALLIER, C
   PASCOLO, S
   PFEIFFER, F
   PHILIPPSEN, P
   PLANTA, RJ
   POHL, FM
   POHL, TM
   POHLMANN, R
   PORTETELLE, D
   PURNELLE, B
   PUZOS, V
   RAD, MR
   RASMUSSEN, SW
   REMACHA, M
   REVUELTA, JL
   RICHARD, GF
   RIEGER, M
   RODRIGUESPOUSADA, C
   ROSE, M
   RUPP, T
   SANTOS, MA
   SCHWAGER, C
   SENSEN, C
   SKALA, J
   SOARES, H
   SOR, F
   STEGEMANN, J
   TETTELIN, H
   THIERRY, A
   TZERMIA, M
   URRESTARAZU, LA
   VANDYCK, L
   VANVLIETREEDIJK, JC
   VALENS, M
   VANDENBOL, M
   VILELA, C
   VISSERS, S
   VON WETTSTEIN, D
   VOSS, H
   WIEMANN, S
   XU, G
   ZIMMERMANN, J
   HAASEMANN, M
   BECKER, I
   MEWES, HW
TI COMPLETE DNA-SEQUENCE OF YEAST CHROMOSOME-XI
SO NATURE
LA English
DT Article
ID open reading frames; saccharomyces-cerevisiae; kb segment; left arm; reveals 5; gene; homolog; protein; genome; fragment
AB The complete DNA sequence of the yeast Saccharomyces cerevisiae chromosome XI has been determined. In addition to a compact arrangement of potential protein coding sequences, the 666,448-base-pair sequence has revealed general chromosome patterns; in particular, alternating regional variations in average base composition correlate with variations in local gene density along the chromosome. Significant discrepancies with the previously published genetic map demonstrate the need for using independent physical mapping criteria.
C1 UNIV PARIS 06, INST PASTEUR, DEPT MOLEC BIOL, UFR 927, F-75724 PARIS 15, FRANCE.
   INST MOLEC BIOL & BIOTECHNOL, FDN RES & TECHNOL HELLAS, GR-71110 IRAKLION, GREECE.
   FREE UNIV BRUSSELS, PHYSIOL CELLULAIRE & GENET LEVURES LAB, B-1050 BRUSSELS, BELGIUM.
   EUROPEAN MOLEC BIOL LAB, D-69117 HEIDELBERG, GERMANY.
   UNIV SALAMANCA, DEPT GENET & MICROBIOL, E-37007 SALAMANCA, SPAIN.
   UNIV AUTONOMA MADRID, E-28049 MADRID, SPAIN.
   FAC CIENCIAS MADRID, CSIC, CTR MOLEC BIOL, E-28049 MADRID, SPAIN.
   FAC SCI AGRON ETAT GEMBLOUX, MICROBIOL LAB, B-5030 GEMBLOUX, BELGIUM.
   UNIV PARIS 11, IGM, GENET MOLEC LAB, CNRS, URA 1354, F-91405 ORSAY, FRANCE.
   INST GULBENKIAN CIENCIAS, GENET MOLEC LAB, P-2781 OEIRAS, PORTUGAL.
   CTR UNIV ORSAY, INST CURIE, BIOL SECT, F-91405 ORSAY 15, FRANCE.
   LAB MOLEK BIOL, D-82152 MARTINSRIED, GERMANY.
   UNIV GIESSEN, INST MIKROBIOL & MOLEK BIOL, D-35392 GIESSEN, GERMANY.
   QUIAGEN GMBH, D-40724 HILDEN, GERMANY.
   UNIV FRANKFURT, INST MIKROBIOL, D-60439 FRANKFURT, GERMANY.
   UNIV MUNICH, INST PHYSIOL CHEM PHYS BIOCHEM & ZELLBIOL, D-80336 MUNICH, GERMANY.
   MAX PLANCK INST BIOCHEM, MIPS, D-82152 MARTINSRIED, GERMANY.
   UNIV DUSSELDORF, INST MIKROBIOL, D-40225 DUSSELDORF, GERMANY.
   BIOTECHNOL & MOLEK BIOL FORSCH, D-69259 WILHELMSFELD, GERMANY.
   UNIV MANCHESTER, INST SCI & TECHNOL, MANCHESTER BIOTECHNOL CTR, MANCHESTER M60 1QD, LANCS, ENGLAND.
   UNIV CATHOLIQUE LOUVAIN, UNITE BIOCHIM PHYSIOL, B-1348 LOUVAIN, BELGIUM.
   COMMISS EUROPEAN COMMUNITIES, B-1049 BRUSSELS, BELGIUM.
   DEUTSCH KREBSFORSCHUNGSZENTRUM, INSERM,U375, UNITE ANGEW TUMORVIROL & VIROL APPL ONCOL,ABT 0610, D-69009 HEIDELBERG, GERMANY.
   JOHN RADCLIFFE HOSP, INST MOLEC MED, OXFORD OX3 9DU, ENGLAND.
   CTR ETUD SACLAY, CEA,DSV,DEPT BIOL CELLULAIRE & MOLEC, SERV BIOCHEM & GENET MOLEC, F-91191 GIF SUR YVETTE, FRANCE.
   UNIV BASEL, BIOZENTRUM, INST ANGEW MIKROBIOL, CH-4056 BASEL, SWITZERLAND.
   VRIJE UNIV AMSTERDAM, BIOCENTRUM AMSTERDAM, INST MOLEC BIOL SCI, DEPT BIOCHEM & MOLEC BIOL, 1081 HV AMSTERDAM, NETHERLANDS.
   UNIV KONSTANZ, FAK BIOL, D-78434 CONSTANCE, GERMANY.
   GESELL ANAL TECH & CONSULTING, D-78467 CONSTANCE, GERMANY.
   CARLSBERG LAB, DEPT PHYSIOL, DK-2500 COPENHAGEN, DENMARK.
C3 Pasteur Network; Universite Paris Cite; Institut Pasteur Paris; Sorbonne Universite; Foundation for Research & Technology - Hellas (FORTH); Universite Libre de Bruxelles; European Molecular Biology Laboratory (EMBL); University of Salamanca; Autonomous University of Madrid; Consejo Superior de Investigaciones Cientificas (CSIC); University of Liege; Universite Paris Saclay; Centre National de la Recherche Scientifique (CNRS); Instituto Gulbenkian de Ciencia; Universite Paris Saclay; UNICANCER; Universite PSL; Institut Curie; Justus Liebig University Giessen; Goethe University Frankfurt; University of Munich; Max Planck Society; Heinrich Heine University Dusseldorf; University of Manchester; Universite Catholique Louvain; Helmholtz Association; German Cancer Research Center (DKFZ); Institut National de la Sante et de la Recherche Medicale (Inserm); University of Oxford; Universite Paris Saclay; CEA; University of Basel; Vrije Universiteit Amsterdam; University of Amsterdam; University of Konstanz
RP DUJON, B (corresponding author), UNIV PARIS 06, INST PASTEUR, DEPT MOLEC BIOL, CNRS, UNITE MOLEC LEVURES 1149, F-75724 PARIS 15, FRANCE.
FU Wellcome Trust Funding Source: Medline
NR 52
TC 328
Z9 702
U1 1
U2 41
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 371
EP 378
DI 10.1038/369371a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400047
PM 8196765
DA 2026-03-10
ER

PT J
AU HUTCHINGS, GJ
   DESMARTINCHOMEL, A
   OLIER, R
   VOLTA, JC
AF HUTCHINGS, GJ
   DESMARTINCHOMEL, A
   OLIER, R
   VOLTA, JC
TI ROLE OF THE PRODUCT IN THE TRANSFORMATION OF A CATALYST TO ITS ACTIVE STATE
SO NATURE
LA English
DT Article
ID maleic-anhydride; raman-spectroscopy; oxidation; butane; oxide
AB OXIDE catalysts, which are used in a broad range of important industrial proccsses(1-4), are generally prepared in the form of a precursor which is converted into the active catalytic form only under well defined reaction conditions. A vanadium phosphorus oxide catalyst is used to effect selective oxidation of n-butane to maleic anhydride: (VO)(2)P2O7 is considered(5-7) to be the main active component, and is prepared from the precursor VOHPO4.O.5H(2)O. Here we use in situ Raman spectroscopy to study the conversion of this precursor to the active form in real time. We find that, during this process, the crystalline structure of VOHPO4.O.5H(2)O becomes totally disordered at the same time as selectivity for maleic anhydride becomes apparent. Furthermore, our results indicate that this Product seems to play a role in bringing about this change; thus, it seems that the selective reaction product assists in the creation of the active sites. We suggest that this phenomenon might be quite general in oxide catalysis.
C1 ECOLE CENT LYON,CNRS,PHYSICOCHIM INTERFACES LAB,F-69131 ECULLY,FRANCE.
   CNRS,INST RECH CATALYSE,F-69626 VILLEURBANNE,FRANCE.
C3 Ecole Centrale de Lyon; Centre National de la Recherche Scientifique (CNRS); Centre National de la Recherche Scientifique (CNRS)
RP HUTCHINGS, GJ (corresponding author), UNIV LIVERPOOL,DEPT CHEM,LEVERHULME CTR INNOVAT CATALYSIS,POB 147,LIVERPOOL L69 3BX,ENGLAND.
NR 12
TC 219
Z9 229
U1 0
U2 38
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 41
EP 45
DI 10.1038/368041a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900046
DA 2026-03-10
ER

PT J
AU ARNASON, U
   GULLBERG, A
AF ARNASON, U
   GULLBERG, A
TI RELATIONSHIP OF BALEEN WHALES ESTABLISHED BY CYTOCHROME-B GENE SEQUENCE COMPARISON
SO NATURE
LA English
DT Article
ID fin whale; balaenoptera-musculus; mitochondrial-dna; physalus; mammals
AB A RECENT revision1 of whale phylogeny suggested that the sperm whale was more closely related to rorquals than to other toothed whales. This made the suborder Odontoceti (toothed whales) paraphyletic, and implied that the latest common ancestor of rorquals and sperm whales may have lived only 10-13 million years ago. This is at variance with palaeontological evidence for the greater antiquity for both mysticetes (baleen whales) and sperm whales, so the Mysticeti, as well as the Odontoceti, must also be paraphyletic if the dates implied in ref. 1 were correct. Here we present a more comprehensive phylogenetic analysis that demonstrates the monophyly of mysticetes and identifies no particular affinity between the sperm whales and rorquals.
RP ARNASON, U (corresponding author), LUND UNIV, DEPT GENET, DIV EVOLUT MOLEC SYST, SOLVEGATAN 29, S-22362 LUND, SWEDEN.
NR 29
TC 104
Z9 127
U1 1
U2 14
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 726
EP 728
DI 10.1038/367726a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100055
PM 8107866
DA 2026-03-10
ER

PT J
AU WHITE, TD
   SUWA, G
   ASFAW, B
AF WHITE, TD
   SUWA, G
   ASFAW, B
TI AUSTRALOPITHECUS RAMIDUS, A NEW SPECIES OF EARLY HOMINID FROM ARAMIS, ETHIOPIA
SO NATURE
LA English
DT Article
ID middle pliocene; kenya; evolution; tabarin; baringo; chimp; dna
AB Seventeen hominoid fossils recovered from Pliocene strata at Aramis, Middle Awash, Ethiopia make up a series comprising dental, cranial and postcranial specimens dated to around 4.4 million years ago. When compared with Australopithecus afarensis and with modern and fossil apes the Aramis fossil hominids are recognized as a new species of Australopithecus-A. ramidus sp. nov. The antiquity and primitive morphology of A. ramidus suggests that it represents a long-sought potential root species for the Hominidae.
C1 UNIV TOKYO, DEPT ANTHROPOL, BUNKYO KU, TOKYO 113, JAPAN.
   ETHIOPIAN MINIST CULTURE & SPORTS AFFAIRS, PALEOANTHROPOL LAB, ADDIS ABABA, ETHIOPIA.
C3 University of Tokyo
RP WHITE, TD (corresponding author), UNIV CALIF BERKELEY, HUMAN EVOLUTIONARY STUDIES LAB, BERKELEY, CA 94720 USA.
NR 32
TC 431
Z9 502
U1 0
U2 64
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 306
EP 312
DI 10.1038/371306a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400044
PM 8090200
DA 2026-03-10
ER

PT J
AU LAGNADO, L
   BAYLOR, DA
AF LAGNADO, L
   BAYLOR, DA
TI CALCIUM CONTROLS LIGHT-TRIGGERED FORMATION OF CATALYTICALLY ACTIVE RHODOPSIN
SO NATURE
LA English
DT Article
ID rod outer segments; retinal rods; guanylate-cyclase; salamander rods; toad rods; photoreceptors; sensitivity; activation; protein; phototransduction
AB BACKGROUND light reduces the gain of phototransduction in retinal rods so that the ability to register changes in light intensity is not prevented by saturation of the cell's response1,2. The gain is reduced by a light-induced fall in the intracellular calcium concentration which results from blockage of Ca2+ entry through the channels  closed by light and continued Ca2+ extrusion by the Na:Ca,K exchanger3-7. Calcium seems to exert several coordinated effects on the cyclic GMP cascade: a fall in [Ca2+] stimulates cGMP synthesis8,9, increases the affinity of the cGMP-gated channel for cGMP10 and accelerates rhodopsin deactivation by phosphorylation11. We now report that lowering intracellular [Ca2+] reduces the catalytic rhodopsin activity produced by light. The effect is operationally equivalent to a fourfold reduction in the number of rhodopsin molecules available for activation. The reduction in gain is cooperative and half-maximal at about 35 nM Ca2+, suggesting that it is mediated by a specific Ca2+-binding protein. Reduced rhodopsin activity in low Ca2+ should contribute to adaptation in background light.
C1 STANFORD UNIV,MED CTR,SCH MED,DEPT NEUROBIOL,STANFORD,CA 94305.
C3 Stanford University
NR 29
TC 117
Z9 125
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 273
EP 277
DI 10.1038/367273a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400057
PM 8121492
DA 2026-03-10
ER

PT J
AU MING, XF
   BURGERING, BMT
   WENNSTROM, S
   CLAESSONWELSH, L
   HELDIN, CH
   BOS, JL
   KOZMA, SC
   THOMAS, G
AF MING, XF
   BURGERING, BMT
   WENNSTROM, S
   CLAESSONWELSH, L
   HELDIN, CH
   BOS, JL
   KOZMA, SC
   THOMAS, G
TI ACTIVATION OF P70/P85 S6 KINASE BY A PATHWAY INDEPENDENT OF P21(RAS)
SO NATURE
LA English
DT Article
ID growth-factor receptor; protein-kinase; signaling pathways; tyrosine kinase; ras; phosphorylation; molecules; p70(s6k); mutant; raf-1
AB THE enzymes p70(s6k) and p85(s6k) two isoforms of the same kinase(1,2) and are important in mitogenesis(2-4). Both isoforms are activated by a complex phosphorylation event(5) and lie on a common signalling pathway(4), distinct from that of the p42(mapk)/p44(mapk) kinases(6). Activation of p42(mapk)/p44(mapk) is triggered by sequential activation of the GDP-GTP exchange factor Sos, the GTP-binding protein p21(ras), and protein kinases p74(raf) and p47(mek) (refs 7-10). As p21(ras) transformed cells have increased S6 phosphorylation(11), we tested whether the p70(s6k)/p85(s6k) signalling pathway bifurcates between p21(ras) and p42(mapk)/p44(mapk). We found that mutants of p74(raf) and p21(ras) blocked activation of epitope-tagged p44(mapk) but not epitope-tagged p70(s6k). Moreover, in cells expressing human platelet-derived growth factor receptors lacking the kinase-insert domain, the growth factor activates p21(ras) but not p70(s6k)/p85(s6k). The critical autophosphorylation site for p70(s6k)/p85(s6k) activation within this domain is a tyrosine at residue 751. Our results show that the p70(s6k)/p85(s6k) signalling pathway is independent of p21(ras), that it bifurcates from the p21(ras) pathway at the receptor, and that it is initiated by autophosphorylation at a specific site.
C1 FRIEDRICH MIESCHER INST, CH-4002 BASEL, SWITZERLAND.
   UNIV UTRECHT, PHYSIOL CHEM LAB, 3584 CG UTRECHT, NETHERLANDS.
   BIOMED CTR, LUDWIG INST CANC RES, S-75124 UPPSALA, SWEDEN.
C3 Friedrich Miescher Institute for Biomedical Research; Utrecht University; Ludwig Institute for Cancer Research
NR 30
TC 208
Z9 218
U1 0
U2 3
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 426
EP 429
DI 10.1038/371426a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500045
PM 8090223
DA 2026-03-10
ER

PT J
AU MOSS, G
   COHEN, S
AF MOSS, G
   COHEN, S
TI TIME TO ABANDON BRUSSELS BID ON PATENTS .2.
SO NATURE
LA English
DT Article
AB After six years of debate, the European Commission's attempts to harmonize biotechnology legislation still face opposition over the patenting of genes. Recent legal experience suggests that its efforts are unnecessary.
RP MOSS, G (corresponding author), TAYLOR JOYNSON GARRETT,LONDON EC4Y 0DX,ENGLAND.
NR 0
TC 0
Z9 0
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 384
EP 384
DI 10.1038/372384a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700061
PM 7969499
DA 2026-03-10
ER

PT J
AU ALMAMOURI, M
   EDWARDS, PP
   GREAVES, C
   SLASKI, M
AF ALMAMOURI, M
   EDWARDS, PP
   GREAVES, C
   SLASKI, M
TI SYNTHESIS AND SUPERCONDUCTING PROPERTIES OF THE STRONTIUM COPPER OXY-FLUORIDE SR2CUO2F2+DELTA
SO NATURE
LA English
DT Article
ID crystal-structure; high-pressure
AB HIGH-PRESSURE synthesis has proved a useful technique for obtaining new, metastable copper oxide superconductors; for example, oxygen insertion into Sr2CuO3 at 6 GPa (ref. 1) yields superconducting Sr2CUO3.1, with transition temperature T-c = 70 K, in which the superconducting CuO2 layers are generated by pressure-induced oxygen migration from apical to equatorial sites. Although the simple structure and high transition temperatures make this family (general formula Sr-n+1CUnO2n+1+delta) of interest, the stringent synthesis conditions limit its value for applications. Here we report that fluorine insertion into Sr2CuO3 at ambient pressure causes related structural rearrangements to give superconducting Sr2CuO2F2+delta with a maximum T-c of 46 K. In this synthesis, the structural changes previously initiated by the thermodynamic effects of high pressure are induced chemically under ambient conditions. The result is a superconducting oxy-fluoride in which fluorine plays a dominant structural role, rather than merely being an electronic dopant as in La2CuO4Fx (ref. 2) and Nd2CuO4-xFy (ref. 3).
C1 UNIV BIRMINGHAM,SCH PHYS & SPACE RES,BIRMINGHAM B15 2TT,ENGLAND.
C3 University of Birmingham
RP ALMAMOURI, M (corresponding author), UNIV BIRMINGHAM,SCH CHEM,BIRMINGHAM B15 2TT,ENGLAND.
NR 13
TC 306
Z9 321
U1 2
U2 108
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 382
EP 384
DI 
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400050
DA 2026-03-10
ER

PT J
AU BERTOLETTI, A
   SETTE, A
   CHISARI, FV
   PENNA, A
   LEVRERO, M
   DECARLI, M
   FIACCADORI, F
   FERRARI, C
AF BERTOLETTI, A
   SETTE, A
   CHISARI, FV
   PENNA, A
   LEVRERO, M
   DECARLI, M
   FIACCADORI, F
   FERRARI, C
TI NATURAL VARIANTS OF CYTOTOXIC EPITOPES ARE T-CELL RECEPTOR ANTAGONISTS FOR ANTIVIRAL CYTOTOXIC T-CELLS
SO NATURE
LA English
DT Article
ID antigen-presenting cells; class-i mhc; infected-cells; virus; hepatitis; complexes; selection; responses; surface; escape
AB IT has been suggested that mutations within immunodominant cytotoxic T-lymphocyte (CTL) epitopes may be exploited by viruses to evade protective immune responses critical for clearance(1-4). Viral escape could originate from passive mechanisms, such as mutations within crucial CTL epitopes, either affecting major histocompatibility complex binding or T-cell antigen receptor (TCR) recognition. Additionally, it has recently been shown that substitutions of TCR contact sites can yield analogue peptides that can still interact with the T-cell receptor but be unable to deliver a full stimulatory signal, thus inducing anergy(5) or acting as an antagonist for the TCR(6-8). We report here that hepatitis B virus isolates derived from two chronically infected patients display variant epitopes that act as natural TCR antagonists with the capacity to inhibit the CTL response to the wild-type epitope. During natural infection, TCR antagonist mutations of CTL epitopes could contribute to the development of viral persistence, especially if the antiviral CTL response is monospecific or the epitope is strongly immunodominant.
C1 UNIV PARMA, CATTEDRA MALATTIE INFETT, I-43100 PARMA, ITALY.
   CYTEL CORP, LA JOLLA, CA 92037 USA.
   SCRIPPS RES INST, DEPT MOLEC & EXPTL MED, LA JOLLA, CA 92037 USA.
   UNIV ROMA LA SAPIENZA, FDN A CESALPINO, ROME, ITALY.
   UNIV ROMA LA SAPIENZA, MED CLIN 1, ROME, ITALY.
   UNIV FLORENCE, CATTEDRA IMMUNOL CLIN & ALLERGOL, I-50134 FLORENCE, ITALY.
C3 University of Parma; Cytel; Scripps Research Institute; Sapienza University Rome; Sapienza University Rome; University of Florence
NR 29
TC 507
Z9 538
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 407
EP 410
DI 10.1038/369407a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400059
PM 8196768
DA 2026-03-10
ER

PT J
AU RUSSELL, TP
   KARIS, TE
   GALLOT, Y
   MAYES, AM
AF RUSSELL, TP
   KARIS, TE
   GALLOT, Y
   MAYES, AM
TI A LOWER CRITICAL ORDERING TRANSITION IN A DIBLOCK COPOLYMER MELT
SO NATURE
LA English
DT Article
ID domain-boundary structure; induced phase separation; block copolymers; films cast; microdomain morphology; microphase separation; thermodynamics; polymers; mixtures; behavior
AB DIBLOCK copolymers, comprised of two distinct homopolymers covalently bonded together at one end, undergo a transition on cooling from a state in which the segments of the blocks are homogeneously mixed to one in which they are segregated locally(1,2). This microphase separation is driven by the enthalpy of unfavourable interactions between segments. Here we report the microphase separation of a diblock copolymer melt on heating. Similar in nature to the lower critical solution temperature seen in polymer mixtures, this lower critical ordering transition is driven by entropic factors-specifically, by a negative volume change on mixing of the blocks. The transition to the microphase-separated state alters the theological and mechanical properties of the copolymer markedly, the material gaining a non-zero equilibrium modulus above the ordering transition. This suggests potential technological applications of these copolymer systems as 'smart' materials.
C1 INST CHARLES SADRON,F-67083 STRASBOURG,FRANCE.
   MIT,DEPT MAT SCI & ENGN,CAMBRIDGE,MA 02139.
C3 Massachusetts Institute of Technology (MIT)
RP RUSSELL, TP (corresponding author), IBM CORP,ALMADEN RES CTR,DIV RES,650 HARRY RD,SAN JOSE,CA 95120, USA.
NR 34
TC 175
Z9 192
U1 1
U2 56
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 729
EP 731
DI 10.1038/368729a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300054
DA 2026-03-10
ER

PT J
AU LEEVERS, SJ
   PATERSON, HF
   MARSHALL, CJ
AF LEEVERS, SJ
   PATERSON, HF
   MARSHALL, CJ
TI REQUIREMENT FOR RAS IN RAF ACTIVATION IS OVERCOME BY TARGETING RAF TO THE PLASMA-MEMBRANE
SO NATURE
LA English
DT Article
ID protein-kinase; monoclonal-antibody; phosphorylation; association; p21(ras); p21ras; mutant; cells
AB A CONSERVED tyrosine kinase-activated signal transduction pathway has recently been identified that comprises the plasma membrane-bound small guanine-nucleotide-binding protein Ras and the protein kinases Raf, MAP-kinase kinase and MAP kinase(1,2). GTP-bound Ras interacts directly with the amino-terminal regulatory domain of Raf(3-8), but although Ras and Raf can be coimmunoprecipitated from ligand-stimulated cells(9,10), Ras-GTP does not stimulate the kinase activity of Raf in vitro(6). Furthermore, we have failed to detect Ras in preparations of active detergent-solubilized Raf, demonstrating that once it is activated, Raf does not require Ras. Whereas Raf is normally cytosolic, in cells expressing active Ras, Raf is associated with the plasma membrane. This led us to investigate whether Ras is required to localize Raf to the plasma membrane in order for Raf to become activated. We fused the membrane localization signal of K-Ras(4B) to the carboxy terminus of Raf. This protein is constitutively active and can be further activated by epidermal growth factor, independently of Ras. Our results indicate that Ras functions as a regulated, membrane-bound anchor for Raf, and that other signal(s) also contribute to Raf activation.
C1 INST CANC RES,CHESTER BEATTY LABS,CELL & MOLEC BIOL SECT,LONDON SW3 6JB,ENGLAND.
C3 University of London; Institute of Cancer Research - UK; Royal Marsden NHS Foundation Trust
NR 29
TC 970
Z9 1065
U1 0
U2 23
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 411
EP 414
DI 10.1038/369411a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400060
PM 8196769
DA 2026-03-10
ER

PT J
AU NELSON, CA
   PETZOLD, SJ
   UNANUE, ER
AF NELSON, CA
   PETZOLD, SJ
   UNANUE, ER
TI PEPTIDES DETERMINE THE LIFE-SPAN OF MHC CLASS-II MOLECULES IN THE ANTIGEN-PRESENTING CELL
SO NATURE
LA English
DT Article
ID major histocompatibility complex; t-cell; immunogenic peptides; surface expression; living cells; b-cells; ia; identification; binding; protein
AB ALTHOUGH many peptides are generated during the intracellular processing of protein antigens, only a few are selected for recognition by the immune system(1-5). The immunodominant epitope of hen egg white lysozyme (HEL) for H-2(k) mice is contained in a tryptic fragment of amino-acid residues 46-61 (refs 6, 7). The core of this T-cell epitope, from amino acids 52 to 61 (DYGILQINSR), contains those residues required for binding to the class II molecule I-A(k) (ref. 7). Most of the naturally processed fragments recovered from I-A(k)-bearing antigen-presenting cells (APCs) cultured with HEL contained this 52-61 core sequence, presented as a nested set of peptides with extensions at both the amino and carboxyl termini(8). We now compare the handling by APCs of peptides containing HEL 52-61 to establish whether there is an advantage for the APC in selecting extended peptides: different complexes between peptides and major histocompatibility complex (MHC) molecules varied greatly in the amount of time associated with the APC, and in their immunogenic strength. This difference in persistence is one of the factors contributing to the selection and immune recognition of peptide-MHC complexes by T cells.
C1 WASHINGTON UNIV,SCH MED,DEPT PATHOL,ST LOUIS,MO 63110.
C3 Washington University (WUSTL)
RP NELSON, CA (corresponding author), WASHINGTON UNIV,SCH MED,CTR IMMUNOL,ST LOUIS,MO 63110, USA.
NR 24
TC 175
Z9 187
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 250
EP 252
DI 10.1038/371250a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000053
PM 8078585
DA 2026-03-10
ER

PT J
AU MANNEY, GL
   FROIDEVAUX, L
   WATERS, JW
   ZUREK, RW
   READ, WG
   ELSON, LS
   KUMER, JB
   MERGENTHALER, JL
   ROCHE, AE
   ONEILL, A
   HARWOOD, RS
   MACKENZIE, I
   SWINBANK, R
AF MANNEY, GL
   FROIDEVAUX, L
   WATERS, JW
   ZUREK, RW
   READ, WG
   ELSON, LS
   KUMER, JB
   MERGENTHALER, JL
   ROCHE, AE
   ONEILL, A
   HARWOOD, RS
   MACKENZIE, I
   SWINBANK, R
TI CHEMICAL DEPLETION OF OZONE IN THE ARCTIC - LOWER STRATOSPHERE DURING WINTER 1992-93
SO NATURE
LA English
DT Article
ID atmosphere research satellite; microwave limb sounder; polar vortex; potential vorticity; mls observations; antarctic ozone; evolution; chlorine; er-2; southern
AB Satellite observations of ozone and chlorine monoxide concentrations during winter 1992-1993 show that in February 1993 chlorine in the lower stratosphere was mostly in chemically reactive forms. Decreases in stratospheric ozone concentration during February and early March 1993 are consistent with chemical destruction by this reactive chlorine. Comparison with changes in the distribution of long-lived chemical and dynamical tracers shows that the observed decrease cannot have been caused solely by dynamical processes.
C1 LOCKHEED PALO ALTO RES LABS,PALO ALTO,CA 94304.
   UNIV READING,CTR GLOBAL ATMOSPHER MODELING,DEPT METEOROL,READING RG6 2AU,BERKS,ENGLAND.
   UNIV EDINBURGH,DEPT METEOROL,EDINBURGH EH9 3JZ,MIDLOTHIAN,SCOTLAND.
   METEOROL OFF,BRACKNELL RG12 2SZ,BERKS,ENGLAND.
C3 Lockheed Martin; University of Reading; University of Edinburgh; Met Office - UK
RP MANNEY, GL (corresponding author), CALTECH,JET PROP LAB,PASADENA,CA 91109, USA.
NR 44
TC 133
Z9 139
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 429
EP 434
DI 10.1038/370429a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700047
DA 2026-03-10
ER

PT J
AU IOST, I
   DREYFUS, M
AF IOST, I
   DREYFUS, M
TI MESSENGER-RNAS CAN BE STABILIZED BY DEAD-BOX PROTEINS
SO NATURE
LA English
DT Article
ID bacteriophage-t7 rna-polymerase; escherichia-coli; messenger-rna; lacz gene; translation; transcription; initiation; expression; helicase; degradation
AB EUBACTERIAL messenger RNAs are synthesized and translated simultaneously; moreover the speed of ribosomes usually matches that of RNA polymerase(1,2). We report here that when in Escherichia coli the host RNA polymerase is replaced by the eightfold faster bacteriophage T7 enzyme for the transcription of the lacZ gene, the beta-galactosidase yield per transcript is depressed 100-fold. But the overexpression of DEAD-box proteins(3) greatly improves this low yield by stabilizing the corresponding transcripts. More generally, it stabilizes inefficiently translated E. coli mRNAs. Ribosome-free mRNA regions, such as those lying behind the fast T7 enzyme or between successive ribosomes on inefficiently translated transcripts, are often unstable(4) and we propose that DEAD-box proteins protect them from endonucleases. These results pinpoint the importance of transcription-translation synchronization for mRNA stability, and reveal an undocumented property of DEAD-box RNA helicases. These proteins have been implicated in a variety of processes involving RNA(5) but not mRNA stability.
C1 ECOLE NORMALE SUPER, CNRS D1302, GENET MOLEC LAB, F-75230 PARIS 05, FRANCE.
C3 Universite PSL; Ecole Normale Superieure (ENS)
NR 29
TC 110
Z9 132
U1 0
U2 4
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 193
EP 196
DI 10.1038/372193a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800060
PM 7526223
DA 2026-03-10
ER

PT J
AU PARPURA, V
   BASARSKY, TA
   LIU, F
   JEFTINIJA, K
   JEFTINIJA, S
   HAYDON, PG
AF PARPURA, V
   BASARSKY, TA
   LIU, F
   JEFTINIJA, K
   JEFTINIJA, S
   HAYDON, PG
TI GLUTAMATE-MEDIATED ASTROCYTE NEURON SIGNALING
SO NATURE
LA English
DT Article
ID calcium waves; hippocampal-neurons; synaptic currents; aspartate; responses; receptors; cultures
AB NEUROTRANSMITTER released from neurons is known to signal to neighbouring neurons and glia(1-3). Here we demonstrate an additional signalling pathway in which glutamate is released from astrocytes and causes an NMDA (N-methyl-D-aspartate) receptor-mediated increase in neuronal calcium. Internal calcium was elevated and glutamate release stimulated by application of the neuroligand bradykinin to cultured astrocytes. Elevation of astrocyte internal calcium was also sufficient to induce glutamate release. To determine whether this released glutamate signals to neurons, we studied astrocyte-neuron co-cultures. Bradykinin significantly increased calcium levels in neurons co-cultured with astrocytes, but not in solitary neurons. The glutamate receptor antagonists D-2-amino-5-phosphonopentanoic acid and D-glutamylglycine prevented bradykinin-induced neuronal calcium elevation. When single astrocytes were directly stimulated to increase internal calcium and release glutamate, calcium levels of adjacent neurons were increased; this increase could be blocked by D-glutamyl-glycine. Thus, astrocytes regulate neuronal calcium levels through the calcium-dependent release of glutamate. -
C1 IOWA STATE UNIV SCI & TECHNOL, DEPT ZOOL & GENET, AMES, IA 50011 USA.
   IOWA STATE UNIV SCI & TECHNOL, DEPT VET ANAT, AMES, IA 50011 USA.
   IOWA STATE UNIV SCI & TECHNOL, NEUROSCI PROGRAM, AMES, IA 50011 USA.
C3 Iowa State University; Iowa State University; Iowa State University
NR 29
TC 1432
Z9 1643
U1 2
U2 94
PU NATURE RESEARCH
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 744
EP 747
DI 10.1038/369744a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100060
PM 7911978
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI THE IRAPUATO APPROACH
SO NATURE
LA English
DT Article
NR 1
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 797
EP 797
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700030
DA 2026-03-10
ER

PT J
AU DAVIS, TL
   NAMSON, JS
AF DAVIS, TL
   NAMSON, JS
TI A BALANCED CROSS-SECTION OF THE 1994 NORTHRIDGE EARTHQUAKE, SOUTHERN CALIFORNIA
SO NATURE
LA English
DT Article
ID whittier-narrows earthquake; western transverse ranges; thrust belt; fault; area; fold
AB THE Northridge earthquake of 17 January 1994(1) was the latest in a series of very damaging, thrust-fault-generated earthquakes to strike California, following the San Fernando(2) 1971, Coalinga(3) 1983, and Whittler Narrows(4,5) 1987 events. Like the last two of these, the Northridge event occurred along a fault that did not reach the surface and which had not been detected by traditional seismic-hazard methods(6,7). Balanced cross-sections(8,9), which flatten and remove the crustal deformation, can be used to identify and quantify the seismic hazard posed by thrust faults. Here we present a balanced cross-section through the Northridge portion of the Transverse Ranges fold-and-thrust belt(10), which shows that the earthquake occurred on what we call the Pico thrust. A cross-section of this sort constructed before the earthquake would have revealed the fault, although it would not have predicted the earthquake. Cross-sectional modelling of the Pico thrust yields an average slip rate of 1.4-1.7 mm yr(-1) and a recurrence interval of Northridge-sized (M(w) 6.7) earthquakes every 1,500-1,800 years. We show that the Pico thrust is the back thrust to the 170-km Elysian Park thrust(3,4) which underlies some of the most densely urbanized portions of the Los Angeles basin.
RP DAVIS, TL (corresponding author), DAVIS & NAMSON CONSULTING GEOLOGISTS,VALENCIA,CA 91355, USA.
NR 23
TC 80
Z9 88
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 167
EP 169
DI 10.1038/372167a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800052
DA 2026-03-10
ER

PT J
AU MADER, HM
   ZHANG, YX
   PHILLIPS, JC
   SPARKS, RSJ
   STURTEVANT, B
   STOLPER, E
AF MADER, HM
   ZHANG, YX
   PHILLIPS, JC
   SPARKS, RSJ
   STURTEVANT, B
   STOLPER, E
TI EXPERIMENTAL SIMULATIONS OF EXPLOSIVE DEGASSING OF MAGMA
SO NATURE
LA English
DT Article
ID eruptions; velocity; flow
AB THE violent release of volatiles in explosive volcanic eruptions is known to cause fragmentation of magma and acceleration of the resulting mixture of gas and pyroclasts to velocities exceeding 100 m s(-1) (ref. 1). But the mechanisms underlying bubble nucleation, flow acceleration and fragmentation are complex and poorly understood. To gain insight into these phenomena, we have simulated explosive eruptions using two model systems that generate expansion rates and flow velocities comparable to those observed in erupting volcanos. The key feature of both experiments is the generation of large supersaturations of carbon dioxide in a liquid phase, achieved either by decompressing CO2-saturated water or by rapid mixing of concentrated K2CO3 and HCl solutions. We show that liberation of CO2 from the aqueous phase is enhanced by violent acceleration of the mixture, which induces strong extensional strain in the developing foam. Fragmentation then occurs when the bubble density and expansion rate are such that the bubble walls rupture. In contrast to conventional models of fragmentation(1,2), we find that expansion and acceleration precede-and indeed cause-fragmentation.
C1 UNIV MICHIGAN, DEPT GEOL SCI, ANN ARBOR, MI 48109 USA.
   UNIV BRISTOL, DEPT GEOL, BRISTOL BS8 1RJ, AVON, ENGLAND.
   CALTECH, GRAD AERONAUT LABS, PASADENA, CA 91125 USA.
   CALTECH, DIV GEOL & PLANETARY SCI, PASADENA, CA 91125 USA.
C3 University of Michigan System; University of Michigan; University of Bristol; California Institute of Technology; California Institute of Technology
RP MADER, HM (corresponding author), UNIV LANCASTER, INST ENVIRONM & BIOL SCI, LANCASTER LA1 4YQ, ENGLAND.
NR 23
TC 97
Z9 104
U1 0
U2 26
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 85
EP 88
DI 10.1038/372085a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800076
DA 2026-03-10
ER

PT J
AU WITTUNG, P
   NIELSEN, PE
   BUCHARDT, O
   EGHOLM, M
   NORDEN, B
AF WITTUNG, P
   NIELSEN, PE
   BUCHARDT, O
   EGHOLM, M
   NORDEN, B
TI DNA-LIKE DOUBLE HELIX FORMED BY PEPTIDE NUCLEIC-ACID
SO NATURE
LA English
DT Article
ID recognition; thymine
AB ALTHOUGH the importance of the nucleobases in the DNA double helix is well understood, the evolutionary significance of the deoxyribose phosphate backbone and the contribution of this chemical entity to the overall helical structure and stability of the double helix is not so clear. Peptide nucleic acid (PNA)1-7 is a DNA analogue with a backbone consisting of N-(2-aminoethyl)glycine units (Fig. 1) which has been shown to mimic DNA in forming Watson-Crick complementary duplexes with normal DNA7. Using circular dichroism spectroscopy we show here that two complementary PNA strands can hybridize to one another to form a helical duplex. There is a seeding of preferred chirality which is induced by the presence of an L- (or D-) lysine residue attached at the carboxy terminus of the PNA strand. These results indicate that a (deoxy)ribose phosphate backbone is not an essential requirement for the formation of double helical DNA-like structures in solution.
C1 PANUM INST,DEPT BIOCHEM B,MED BIOTECHNOL RES CTR,BLEGDAMSVEJ 3C,DK-2200 N COPENHAGEN,DENMARK.
   CHALMERS UNIV TECHNOL,DEPT PHYS CHEM,S-41296 GOTHENBURG,SWEDEN.
   HC ORSTED INST,DEPT ORGAN CHEM,DK-2100 COPENHAGEN 0,DENMARK.
C3 Chalmers University of Technology; University of Copenhagen
NR 12
TC 454
Z9 565
U1 1
U2 90
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 561
EP 563
DI 10.1038/368561a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500059
PM 8139692
DA 2026-03-10
ER

PT J
AU HONG, KS
   DRISCOLL, M
AF HONG, KS
   DRISCOLL, M
TI A TRANSMEMBRANE DOMAIN OF THE PUTATIVE CHANNEL SUBUNIT MEC-4 INFLUENCES MECHANOTRANSDUCTION AND NEURODEGENERATION IN C-ELEGANS
SO NATURE
LA English
DT Article
ID touch receptor neurons; caenorhabditis-elegans; gene
AB ABERRANT ion channel activity plays a causative role in several human disorders1-3. Inappropriately regulated channel activity also appears to be the basis for neurodegeneration induced by dominant mutations of Caenorhabditis elegans mec-4 (mec-4(d)), a member of the degenerin gene family postulated to encode a subunit of a mechanosensory channel4. The degenerin gene family has been defined by two C. elegans genes, mec-4 and deg-1 (ref. 5), which can mutate to gain-of-function alleles that induce degeneration of specific groups of neurons. A related mammalian gene, rat alpha-rENaC, induces an amiloride-sensitive Na+ current when introduced to Xenopus oocytes6, strongly suggesting that degenerin genes encode ion channel proteins. Deduced amino-acid sequences of the degenerins include two predicted membrane-spanning domains6,7. Here we show that conserved amino acids within the second membrane-spanning domain (MSDII) are critical for MEC-4 activity and that specific substitutions within MSDII, whether encoded in cis or in trans to a mec-4(d) mutation, block or delay the onset of degeneration. Remarkably, MSDII from two other family members, C. elegans deg-1 (ref. 5) and rat alpha-rENaC (ref. 6), can functionally substitute for MEC-4 MSDII in chimaeric proteins. Our results support a structural model for a mechanosensory channel in which multiple MEC-4 subunits are oriented such that MSDII lines the channel pore, and a neurodegeneration model in which aberrant ion flow through this channel is a key event.
C1 RUTGERS UNIV,CTR ADV BIOTECHNOL & MED,DEPT MOLEC BIOL & BIOCHEM,PISCATAWAY,NJ 08855.
C3 Rutgers University System; Rutgers University New Brunswick
NR 23
TC 185
Z9 213
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 470
EP 473
DI 10.1038/367470a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900057
PM 8107806
DA 2026-03-10
ER

PT J
AU GRANDE, T
   HOLLOWAY, JR
   MCMILLAN, PF
   ANGELL, CA
AF GRANDE, T
   HOLLOWAY, JR
   MCMILLAN, PF
   ANGELL, CA
TI NITRIDE GLASSES OBTAINED BY HIGH-PRESSURE SYNTHESIS
SO NATURE
LA English
DT Article
ID lithium phosphorus nitride; oxynitride glasses; crystal-structure; li7pn4; lipn2
AB THE incorporation of nitrogen in oxide glasses can lead to improved physical properties such as hardness and refractive index(1-4); one might accordingly expect to see a further improvement in glasses containing nitrogen as the only anion. But while there are now many examples of non-oxide glasses in the halide and chalcogenide families(5-8), the formation of pure nitride glasses has not hitherto been demonstrated. Here we report the formation of glasses in the system Li3N-Ca3N2-P3N5, by the rapid quenching of fused mixtures of the nitrides at high pressures. The use of high-pressure conditions prevents thermal decomposition of the nitride mixtures to gaseous nitrogen. The new nitride glasses are stable in air, have remarkably high refractive indices (1.97-2.0), hardness exceeding that of silica glass, and high glass transition temperatures (T-g > 700 degrees C).
C1 ARIZONA STATE UNIV,MAT RES GRP HIGH PRESSURE MAT SYNTH,TEMPE,AZ 85287.
C3 Arizona State University; Arizona State University-Tempe
NR 19
TC 27
Z9 30
U1 2
U2 35
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 43
EP 45
DI 10.1038/369043a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000046
DA 2026-03-10
ER

PT J
AU THUNNISSEN, AMWH
   DIJKSTRA, AJ
   KALK, KH
   ROZEBOOM, HJ
   ENGEL, H
   KECK, W
   DIJKSTRA, BW
AF THUNNISSEN, AMWH
   DIJKSTRA, AJ
   KALK, KH
   ROZEBOOM, HJ
   ENGEL, H
   KECK, W
   DIJKSTRA, BW
TI DOUGHNUT-SHAPED STRUCTURE OF A BACTERIAL MURAMIDASE REVEALED BY X-RAY CRYSTALLOGRAPHY
SO NATURE
LA English
DT Article
ID soluble lytic transglycosylase; escherichia-coli; bacteriophage-t4 lysozyme; proteins; detector
AB THE integrity of the bacterial cell wall depends on the balanced action of several peptidoglycan (murein) synthesizing and degrading enzymes1,2. Penicillin inhibits the enzymes responsible for peptide crosslinks in the peptidoglycan polymer3. Enzymes that act solely on the glycosidic bonds are insensitive to this antibiotic, thus offering a target for the design of antibiotics distinct from the beta-lactams. Here we report the X-ray structure of the periplasmic soluble lytic transglycosylase (SLT; M(r) 70,000) from Escherichia coli. This unique bacterial exomuramidase cleaves the beta-1,4-glycosidic bonds of peptidoglycan to produce small 1,6-anhydromuropeptides4-6. The structure of SLT reveals a 'superhelical' ring of alpha-helices with a separate domain on top which resembles the fold of lysozyme. Site-directed mutagenesis and a crystallographic inhibitor-binding study confirmed that the lysozyme-like domain contains the active site of SLT.
C1 UNIV GRONINGEN,DEPT CHEM,BIOSON RES INST,NIJENBORGH 4,9747 AG GRONINGEN,NETHERLANDS.
   F HOFFMANN LA ROCHE & CO LTD,PHARMA RES DEPT,CH-4002 BASEL,SWITZERLAND.
C3 University of Groningen; Roche Holding
NR 27
TC 149
Z9 164
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 750
EP 754
DI 10.1038/367750a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100062
PM 8107871
DA 2026-03-10
ER

PT J
AU SIEGFRIED, E
   WILDER, EL
   PERRIMON, N
AF SIEGFRIED, E
   WILDER, EL
   PERRIMON, N
TI COMPONENTS OF WINGLESS SIGNALING IN DROSOPHILA
SO NATURE
LA English
DT Article
ID segment-polarity gene; molecular-cloning; human plakoglobin; protein; armadillo; expression; product; homolog; encodes; melanogaster
AB THE determination of specific cell fates and polarity within each segmental unit of the Drosophila embryo involves the products of the segment polarity genes1. One of these, wingless (wg), encodes a secreted protein 2,3 that is homologous to the mammalian protooncogene Wnt-1 (refs 4, 5). In the embryonic epidermis, wg is expressed in a single row of cells within each segmental unit, although its activity is required for the correct patterning of most of the epidermis4,6. Initially Wg signals to adjacent posterior cells, maintaining engrailed (en) expression7,8. Later during embryogenesis, wg specifies the differentiation of naked cuticle9.  Wg signalling functions by inactivating or antagonizing the activity of zeste-white 3 (zw3)10.  We have investigated the requirement in the Wg signal transduction pathway for the three genes armadillo (arm)11,12, dishevelled (dsh) and porcupine (porc)13, all of which have embryonic mutant phenotypes similar to wg. Our results indicate that dsh and porc act upstream of zw3, and arm acts down-stream of zw3.
C1 HARVARD UNIV,SCH MED,HOWARD HUGHES MED INST,BOSTON,MA 02115.
C3 Howard Hughes Medical Institute; Harvard University; Harvard Medical School
RP SIEGFRIED, E (corresponding author), HARVARD UNIV,SCH MED,DEPT GENET,200 LONGWOOD AVE,BOSTON,MA 02115, USA.
NR 33
TC 299
Z9 335
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 76
EP 80
DI 10.1038/367076a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500063
PM 8107779
DA 2026-03-10
ER

PT J
AU JOHNSTON, JA
   KAWAMURA, M
   KIRKEN, RA
   CHEN, YQ
   BLAKE, TB
   SHIBUYA, K
   ORTALDO, JR
   MCVICAR, DW
   O'SHEA, JJ
AF JOHNSTON, JA
   KAWAMURA, M
   KIRKEN, RA
   CHEN, YQ
   BLAKE, TB
   SHIBUYA, K
   ORTALDO, JR
   MCVICAR, DW
   O'SHEA, JJ
TI PHOSPHORYLATION AND ACTIVATION OF THE JAK-3 JANUS KINASE IN RESPONSE TO INTERLEUKIN-2
SO NATURE
LA English
DT Article
ID protein-tyrosine kinase; gamma signal-transduction; receptor-beta; interferon-alpha/beta; il-2; subunit; chain; pathway
AB LUTERLEUKIN-2 is an autocrine growth factor for T cells(1,2) which also activates other cells including B cells(3) and natural killer cells(4). The subunits of the interleukin-2 receptor (IL-2R) lack intrinsic enzymatic activity, but protein tyrosine phosphorylation is a critical event following ligand binding and src family kinases, such as Lck, are known to be activated by IL-2 (refs 5-9). However, IL-2 signalling can occur in the absence of receptor interaction with Lck, suggesting that other protein tyrosine kinases might be important(10). Here we report that a new member of the Janus family of kinases (Jak-3) is coupled to the IL-2R in human peripheral blood T cells and natural killer cells.
C1 NCI, FREDERICK CANC RES & DEV CTR, BIOL RESPONSE MODIFIERS PROGRAM, MOLEC IMMUNOREGULAT LAB, FREDERICK, MD 21702 USA.
   NCI, FREDERICK CANC RES & DEV CTR, PRI DYNCORP, BIOL CARCINOGENESIS & DEV PROGRAM, FREDERICK, MD 21702 USA.
   NCI, FREDERICK CANC RES & DEV CTR, ADV BIOSCI LABS INC, FREDERICK, MD 21702 USA.
C3 National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI); Science Applications International Corporation (SAIC); SAIC-Frederick; National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI); Science Applications International Corporation (SAIC); SAIC-Frederick; Science Applications International Corporation (SAIC); SAIC-Frederick; National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI)
RP JOHNSTON, JA (corresponding author), NCI, FREDERICK CANC RES & DEV CTR, EXPTL IMMUNOL LAB, LEUKOCYTE CELL BIOL SECT, FREDERICK, MD 21702 USA.
NR 28
TC 567
Z9 623
U1 0
U2 12
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 151
EP 153
DI 10.1038/370151a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400060
PM 8022485
DA 2026-03-10
ER

PT J
AU KELLER, M
   BLOCHL, E
   WACHTERSHAUSER, G
   STETTER, KO
AF KELLER, M
   BLOCHL, E
   WACHTERSHAUSER, G
   STETTER, KO
TI FORMATION OF AMIDE BONDS WITHOUT A CONDENSATION AGENT AND IMPLICATIONS FOR ORIGIN OF LIFE
SO NATURE
LA English
DT Article
ID pyrite formation; evolution; biochemistry; world
AB AMIDE bonds are of central importance for biochemistry; in the guise of peptide bonds, they form the backbone of proteins. The formation of amide bonds without the assistance of enzymes poses a major challenge for theories of the orgin of life. Enzyme-free formation of amide bonds between amino acids has been demonstrated in the presence of condensing agents such as cyanamide(1-4) Here we report the formation of amide bonds in aqueous solution in the absence of any condensing agent. We find that the formation of pyrite (FeS2) from FeS and H2S can provide the driving force for reductive acetylation of amino acids,vith mercaptoacetic acid (HSCH2COOH). The redox energy of pyrite formation permits the activation of the carboxylic acid group, which is converted to a species that reacts readily with amines. This process provides support for the chemo-autotrophic theory(5-8) for the origin of life, in which pyrite formation supplies the energy source for the first autocatalytic reproduction cycle.
C1 LEHRSTUHL MIKROBIOL,D-93040 REGENSBURG,GERMANY.
NR 15
TC 62
Z9 67
U1 3
U2 68
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 836
EP 838
DI 10.1038/368836a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700065
PM 8159243
DA 2026-03-10
ER

PT J
AU CHEN, S
   ROSEMAN, AM
   HUNTER, AS
   WOOD, SP
   BURSTON, SG
   RANSON, NA
   CLARKE, AR
   SAIBIL, HR
AF CHEN, S
   ROSEMAN, AM
   HUNTER, AS
   WOOD, SP
   BURSTON, SG
   RANSON, NA
   CLARKE, AR
   SAIBIL, HR
TI LOCATION OF A FOLDING PROTEIN AND SHAPE CHANGES IN GROEL-GROES COMPLEXES IMAGED BY CRYOELECTRON MICROSCOPY
SO NATURE
LA English
DT Article
ID chaperonin groel; central cavity; binding; surface; cycle; atp
AB PROTEIN folding mediated by the molecular chaperone GroEL occurs by its binding to non-native polypeptide substrates and is driven by ATP hydrolysis(1). Both of these processes are influenced by the reversible association of the co-protein, GroES (refs 2-4). GroEL and other chaperonin 60 molecules(5) are large, cylindrical oligomers consisting of two stacked heptameric rings of subunits(6,7); each ring forms a cage-like structure(8) thought to bind polypeptides in a central cavity(8-10). Chaperonins play a passive role in folding by binding or sequestering folding proteins to prevent their aggregation(11-13), but they may also actively unfold substrate proteins trapped in misfolded forms, enabling them to assume productive folding conformations(14-16). Biochemical studies show that GroES improves the efficiency of GroEL function(2,3,17), but the structural basis for this is unknown. Here we report the first direct visualization, by cryo-electron microscopy, of a non-native protein substrate (malate dehydrogenase) bound to the mobile, outer domains at one end of GroEL. Addition of GroES to GroEL in the presence of ATP causes a dramatic hinge opening of about 60 degrees. GroES binds to the equivalent surface of the GroEL outer domains, but on the opposite end of the GroEL oligomer to the protein substrate.
C1 UNIV BRISTOL,DEPT BIOCHEM,BRISTOL BS8 1TD,ENGLAND.
   UNIV BRISTOL,CTR MOLEC RECOGNIT,BRISTOL BS8 1TD,ENGLAND.
C3 University of Bristol; University of Bristol
RP CHEN, S (corresponding author), UNIV LONDON BIRKBECK COLL,DEPT CRYSTALLOG,MALET ST,LONDON WC1E 7HX,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 27
TC 336
Z9 351
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 261
EP 264
DI 10.1038/371261a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000057
PM 7915827
DA 2026-03-10
ER

PT J
AU EGOLF, DA
   GREENSIDE, HS
AF EGOLF, DA
   GREENSIDE, HS
TI RELATION BETWEEN FRACTAL DIMENSION AND SPATIAL CORRELATION LENGTH FOR EXTENSIVE CHAOS
SO NATURE
LA English
DT Article
ID ginzburg-landau equation; systems; attractors; exponents
AB SUSTAINED nonequilibrium systems can be characterized by a fractal dimension D greater than or equal to 0, which can be considered to be a measure of the number of independent degrees of freedom(1). The dimension D is usually estimated from time series' but the available algorithms are unreliable and difficult to apply when D is larger than about 5 (refs 3, 4). Recent advances in experimental technique(5-8) and in parallel computing have now made possible the study of big systems with large fractal dimensions, raising new questions about what physical properties determine D and whether these physical properties can be used in place of time-series to estimate large fractal dimensions. Numerical simulations(9-11) suggest that sufficiently large homogeneous systems will generally be extensively chaotic(12), which means that D increases linearly with the system volume V. Here we test an hypothesis that follows from this observation: that the fractal dimension of extensive chaos is determined by the average spatial disorder as measured by the spatial correlation length xi associated with the equal-time two-point correlation function-a measure of the correlations between different regions of the system. We find that the hypothesis fails for a representative spatiotemporal chaotic system. Thus, if there is a length scale that characterizes homogeneous extensive chaos, it is not the characteristic length scale of spatial disorder.
C1 DUKE UNIV,CTR NONLINEAR & COMPLEX SYST,DURHAM,NC 27708.
   DUKE UNIV,DEPT COMP SCI,DURHAM,NC 27708.
C3 Duke University; Duke University
RP EGOLF, DA (corresponding author), DUKE UNIV,DEPT PHYS,DURHAM,NC 27708, USA.
NR 23
TC 85
Z9 91
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 129
EP 131
DI 10.1038/369129a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100042
DA 2026-03-10
ER

PT J
AU DECETY, J
   PERANI, D
   JEANNEROD, M
   BETTINARDI, V
   TADARY, B
   WOODS, R
   MAZZIOTTA, JC
   FAZIO, F
AF DECETY, J
   PERANI, D
   JEANNEROD, M
   BETTINARDI, V
   TADARY, B
   WOODS, R
   MAZZIOTTA, JC
   FAZIO, F
TI MAPPING MOTOR REPRESENTATIONS WITH POSITRON EMISSION TOMOGRAPHY
SO NATURE
LA English
DT Article
ID anterior cingulate cortex; pet images; voluntary; movements
AB BRAIN activity was mapped in normal subjects during passive observation of the movements of an 'alien' hand and while imagining grasping objects with their own hand. None of the tasks required actual movement. Shifting from one mental task to the other greatly changed the pattern of brain activation. During observation of hand movements, activation was mainly found in visual cortical areas, but also in subcortical areas involved in motor behaviour, such as the basal ganglia and the cerebellum. During motor imagery, cortical and subcortical areas related to motor preparation and programming were strongly activated. These data support the notion that motor learning during observation of movements and mental practice involves rehearsal of neural pathways related to cognitive stages of motor control(1-3).
C1 UNIV MILAN,SCI INST H SAN RAFFAELE,INB,CNR,I-20132 MILAN,ITALY.
   UNIV CALIF LOS ANGELES,SCH MED,DEPT NEUROL,DIV BRAIN MAPPING,LOS ANGELES,CA 90024.
C3 Vita-Salute San Raffaele University; IRCCS Ospedale San Raffaele; University of Milan; Consiglio Nazionale delle Ricerche (CNR); University of California System; University of California Los Angeles; University of California Los Angeles Medical Center; David Geffen School of Medicine at UCLA
RP DECETY, J (corresponding author), INSERM,U94,16 AVE DOYEN LEPINE,F-69500 BRON,FRANCE.
NR 17
TC 793
Z9 844
U1 0
U2 45
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 600
EP 602
DI 10.1038/371600a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900050
PM 7935791
DA 2026-03-10
ER

PT J
AU GERSZTEN, RE
   CHEN, J
   ISHII, M
   ISHII, K
   WANG, L
   NANEVICZ, T
   TURCK, CW
   VU, TKH
   COUGHLIN, SR
AF GERSZTEN, RE
   CHEN, J
   ISHII, M
   ISHII, K
   WANG, L
   NANEVICZ, T
   TURCK, CW
   VU, TKH
   COUGHLIN, SR
TI SPECIFICITY OF THE THROMBIN RECEPTOR FOR AGONIST PEPTIDE IS DEFINED BY ITS EXTRACELLULAR SURFACE
SO NATURE
LA English
DT Article
ID neurokinin-1 receptor; activation; mechanism; binding; domains; cloning
AB G-PROTEIN-COUPLED receptors for catecholamines and some other small ligands are activated when agonists bind to the transmembrane region of the receptor1. The docking interactions through which peptide agonists activate their receptors are less well characterized2-7. The thrombin receptor is a specialized peptide receptor. it is activated by binding its tethered ligand domain, which is unmasked upon receptor cleavage by thrombin8,9. Human and Xenopus thrombin receptor homologues are each selectively activated by the agonist peptide representing their respective tethered ligand domains. Here we identify receptor domains that confer this agonist specificity by replacing the Xenopus receptor's amino-terminal exodomain and three extracellular loops with the corresponding human structures. This switches receptor specificity from Xenopus to human. The specificity of these thrombin receptors for their respective peptide agonists is thus determined by their extracellular surfaces. Our results indicate that agonist interaction with extracellular domains is important for thrombin receptor activation.
C1 UNIV CALIF SAN FRANCISCO,CARDIOVASC RES INST,SAN FRANCISCO,CA 94143.
   UNIV CALIF SAN FRANCISCO,DAIICHI RES CTR,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco; University of California System; University of California San Francisco
NR 19
TC 202
Z9 223
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 648
EP 651
DI 10.1038/368648a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200064
PM 8145852
DA 2026-03-10
ER

PT J
AU FISCHER, TP
   MORRISSEY, MM
   CALVACHE, ML
   GOMEZ, D
   TORRES, R
   STIX, J
   WILLIAMS, SN
AF FISCHER, TP
   MORRISSEY, MM
   CALVACHE, ML
   GOMEZ, D
   TORRES, R
   STIX, J
   WILLIAMS, SN
TI CORRELATIONS BETWEEN SO2 FLUX AND LONG-PERIOD SEISMICITY AT GALERAS VOLCANO
SO NATURE
LA English
DT Article
ID driven crack; tremor; hazard
AB THE 14 January 1993 eruption of Galeras volcano, in Colombia, which killed six scientists and three tourists(1), was followed by a larger eruption on 23 March 1993(2). Both eruptions were preceded by episodes of long-period seismicity. The source of long-period seismic events has been modelled extensively(3-8), as the resonance within a fluid-filled crack induced by pressure transients in the fluid(5-7). Here,ve use the SO2 flux from Galeras volcano, measured remotely, to infer the degassing history during the episode of long-period events preceding the 23 March eruption. SO2 flux and long-period seismicity have been monitored separately elsewhere to forecast volcanic activity(9-13). Our results show how the combination and correlation of the two methods can be used to interpret the movement of gases from the magma body to the surface, and to monitor the pressure buildup leading to an eruption at explosive volcanoes.
C1 INGEOMINAS,OBSERV VOLCANOL SUR,PASTO,COLOMBIA.
   UNIV MONTREAL,DEPT GEOL,MONTREAL H3C 3J7,PQ,CANADA.
C3 Universite de Montreal
RP FISCHER, TP (corresponding author), ARIZONA STATE UNIV,DEPT GEOL,TEMPE,AZ 85287, USA.
NR 26
TC 92
Z9 101
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 135
EP 137
DI 10.1038/368135a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000062
DA 2026-03-10
ER

PT J
AU MULDER, FM
   STEGINK, TA
   THIEL, RC
   DEJONGH, LJ
   SCHMID, G
AF MULDER, FM
   STEGINK, TA
   THIEL, RC
   DEJONGH, LJ
   SCHMID, G
TI METALLIC BEHAVIOR IN A PT(309) CLUSTER REVEALED BY AU-197 MOSSBAUER-SPECTROSCOPY
SO NATURE
LA English
DT Article
AB SMALL Metal clusters, containing of the order of 10 to 10,000 atoms, are of interest both for exploring the fundamental question of how atomic-scale properties develop into bulk properties and because such clusters are expected to have interesting optical, electronic and magnetic properties1. The expectation is that bulk-like metallic behaviour will become increasingly evident as the cluster size increases, but at what stage bulk properties appear is not yet clear. Here we present results of a study of the platinum cluster compound Pt309(Phen*)36O30+/-10 (refs 2-4), in which we use Mossbauer spectroscopy to investigate the bonding environment of the Pt atoms. Because Pt lacks a good Mossbauer isotope, we transform a fraction of the Pt-196 atoms in the clusters into Mossbauer nuclei Au-197 by neutron irradiation. The resulting spectra show that the inner (147-atom) core of the Pt cluster exhibits a metallic character like that in the bulk metal, whereas the surface atoms are not bulk-like. These bulk-like metallic properties may be acquired by metal-cluster cores as small as about 150 atoms.
C1 UNIV GH ESSEN,INST ANORGAN CHEM,D-45117 ESSEN,GERMANY.
C3 University of Duisburg Essen
RP MULDER, FM (corresponding author), LEIDEN UNIV,KAMERLINGH ONNES LAB,POB 9506,2300 RA LEIDEN,NETHERLANDS.
NR 14
TC 37
Z9 37
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 716
EP 718
DI 10.1038/367716a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100051
DA 2026-03-10
ER

PT J
AU HARLOS, K
   MARTIN, DMA
   OBRIEN, DP
   JONES, EY
   STUART, DI
   POLIKARPOV, I
   MILLER, A
   TUDDENHAM, EGD
   BOYS, CWG
AF HARLOS, K
   MARTIN, DMA
   OBRIEN, DP
   JONES, EY
   STUART, DI
   POLIKARPOV, I
   MILLER, A
   TUDDENHAM, EGD
   BOYS, CWG
TI CRYSTAL-STRUCTURE OF THE EXTRACELLULAR REGION OF HUMAN TISSUE FACTOR
SO NATURE
LA English
DT Article
ID factor-vii; protein crystallography; human cd4; domains; receptor; fragment; complex; binding
AB TISSUE factor is a cell-surface glycoprotein receptor which initiates the blood coagulation cascade after vessel injury by interacting with blood clotting factor VII/VIIa and which is implicated in various pathological processes(1). When bound to tissue factor, factor VII is readily converted to the active protease factor VIIa by trace amounts of factors Xa, IXa or VIIa. Human tissue factor consists of 263 residues, the first 219 of which comprise the extracellular region(2). We have determined the crystal structure of the extracellular region at a resolution of 2.2 Angstrom. Tissue factor consists of two immunoglobulin-like domains associated through an extensive, novel, interdomain interface region. The binding site for factor VII lies at the interface region and involves residues from domain 1 and an extended loop (binding 'finger') of domain 2. This is the first reported structure of a representative of the class 2 cytokine receptor family, which also includes interferon-alpha, interferon-gamma (refs 2, 3) and interleukin-10 (ref. 4) receptors.
C1 UNIV EDINBURGH, SCH MED, DEPT BIOCHEM, EDINBURGH EH8 9XD, SCOTLAND.
   UNIV OXFORD, MOLEC BIOPHYS LAB, OXFORD OX1 3QU, ENGLAND.
   OXFORD CTR MOLEC SCI, OXFORD OX1 3QU, ENGLAND.
   MRC, CLIN RES CTR, HAEMOSTASIS RES GRP, HARROW HA1 3UJ, MIDDX, ENGLAND.
C3 University of Edinburgh; University of Oxford; University of Oxford; Medical Research Council Clinical Trials Unit
NR 29
TC 217
Z9 235
U1 0
U2 5
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 662
EP 666
DI 10.1038/370662a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000054
PM 8065454
DA 2026-03-10
ER

PT J
AU WANG, M
   VANENCKEVORT, WJP
   MING, NB
   BENNEMA, P
AF WANG, M
   VANENCKEVORT, WJP
   MING, NB
   BENNEMA, P
TI FORMATION OF A MESH-LIKE ELECTRODEPOSIT INDUCED BY ELECTROCONVECTION
SO NATURE
LA English
DT Article
ID electrochemical deposition; growth; morphology; zinc
AB ELECTRODEPOSITION of metals such as copper and zinc from solutions of their salts may give rise to ramified metal deposits which show a range of growth morphologies1-9. Our understanding of the factors that determine growth morphology is still very limited, in part because different morphologies may be observed even under similar growth conditions4,5. It is thought9 that uncontrolled convective processes at the tips of the deposit branches may play a role in these discrepancies. Here we show that convective effects, which we can visualize directly, in the electrodeposition of iron from FeSO4 solution, can generate a mesh-like pattern, a morphology that has not been reported previously. Convection can be diminished by altering the pH, whereupon we see a transition to a dense branching morphology. Our results show that convective effects do indeed play an important part in determining pattern selection during electrodeposition.
C1 NANJING UNIV,NATL LAB SOLID STATE MICROSTRUCT,NANJING 210008,PEOPLES R CHINA.
C3 Nanjing University
RP WANG, M (corresponding author), CATHOLIC UNIV NIJMEGEN,FAC SCI,SOLID STATE CHEM LAB,RIM,6525 ED NIJMEGEN,NETHERLANDS.
NR 15
TC 73
Z9 81
U1 2
U2 69
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 438
EP 441
DI 10.1038/367438a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900047
DA 2026-03-10
ER

PT J
AU SHAKKED, Z
   GUZIKEVICHGUERSTEIN, G
   FROLOW, F
   RABINOVICH, D
   JOACHIMIAK, A
   SIGLER, PB
AF SHAKKED, Z
   GUZIKEVICHGUERSTEIN, G
   FROLOW, F
   RABINOVICH, D
   JOACHIMIAK, A
   SIGLER, PB
TI DETERMINANTS OF REPRESSOR-OPERATOR RECOGNITION FROM THE STRUCTURE OF THE TRP OPERATOR BINDING-SITE
SO NATURE
LA English
DT Article
ID dna double helix; t-c-g; b-dna; resolution; crystal; complex
AB ON the basis of the crystal structure of the trp repressor/operator complex1, it has been proposed that the specificity of the interaction can be explained not only by direct hydrogen bonding and non-polar contacts between the protein and the bases of its target DNA, but also by indirect structural effects and water-mediated interactions. To understand the contribution of DNA structure and hydration in this context, the structure of the free DNA must be compared with its structure when complexed with the protein. Here we present the high-resolution crystal structure of the trp operator region that is most important in the recognition process. By comparing the free and bound states of the DNA regulatory sequence, we show that the structure and hydration of the DNA target are important elements in its recognition by the repressor protein.
C1 YALE UNIV,HOWARD HUGHES MED INST,DEPT MOLEC BIOPHYS & BIOCHEM,NEW HAVEN,CT 06510.
C3 Howard Hughes Medical Institute; Yale University
RP SHAKKED, Z (corresponding author), WEIZMANN INST SCI,DEPT STRUCT BIOL,IL-76100 REHOVOT,ISRAEL.
NR 22
TC 168
Z9 180
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 469
EP 473
DI 10.1038/368469a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000068
PM 8133895
DA 2026-03-10
ER

PT J
AU SOLDATI, T
   SHAPIRO, AD
   SVEJSTRUP, ABD
   PFEFFER, SR
AF SOLDATI, T
   SHAPIRO, AD
   SVEJSTRUP, ABD
   PFEFFER, SR
TI MEMBRANE TARGETING OF THE SMALL GTPASE RAB9 IS ACCOMPANIED BY NUCLEOTIDE EXCHANGE
SO NATURE
LA English
DT Article
ID gdp dissociation inhibitor; binding protein; vesicular transport; activating protein; endocytic pathway; purification; cytosol
AB THE Rab GTPases are key regulators of vesicular transport(1-6). A fraction of Rab proteins is present in the cytosol, bound with GDP, complexed tb a protein termed GDI(7-10). Rab9 is localized primarily to late endosomes, where it aids the transport of mannose 6-phosphate receptors to the trans-Golgi network(11). It has been proposed that Rab proteins are delivered to specific membranes by GDI, and that this process is accompanied by the exchange of bound GDP for GTP(1-3). In addition, Rab localization requires carboxy-terminal prenylation and specific structural determinants(12-14). Here we describe the reconstitution of the selective targeting of prenylated Rab9 protein onto late endosome membranes and show that this process is accompanied by endosome-triggered nucleotide exchange.
C1 STANFORD UNIV,SCH MED,DEPT BIOCHEM,STANFORD,CA 94305.
C3 Stanford University
NR 26
TC 169
Z9 193
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 76
EP 78
DI 10.1038/369076a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000057
PM 8164745
DA 2026-03-10
ER

PT J
AU WIEDMANN, B
   SAKAI, H
   DAVIS, TA
   WIEDMANN, M
AF WIEDMANN, B
   SAKAI, H
   DAVIS, TA
   WIEDMANN, M
TI A PROTEIN COMPLEX REQUIRED FOR SIGNAL-SEQUENCE-SPECIFIC SORTING AND TRANSLOCATION
SO NATURE
LA English
DT Article
ID endoplasmic-reticulum membrane; large ribosomal-subunit; recognition particle; nascent preprolactin; escherichia-coli; cross-linking; polypeptide-chains; receptor; transcription; cell
AB We have purified a nascent-polypeptide-associated complex (NAC) which prevents short ribosome-associated nascent polypeptides from inappropriate interactions with proteins in the cytosol. NAC binds nascent-polypeptide domains emerging from ribosomes unless a signal peptide is fully exposed. Depletion of cytosolic proteins (including NAC) from ribosomes carrying nascent polypeptides allows the signal recognition particle (SRP) to crosslink to polypeptides irrespective of whether or not they contain signal peptides. In the absence of cytosol, proteins lacking signal peptides can be mistranslocated into the endoplasmic reticulum in vitro, albeit with low efficiency. Readdition of NAC restores the specificity of SRP and fidelity of translocation.
C1 MEM SLOAN KETTERING CANC CTR, CELLULAR BIOCHEM & BIOPHYS PROGRAM, NEW YORK, NY 10021 USA.
C3 Memorial Sloan Kettering Cancer Center
NR 30
TC 370
Z9 419
U1 2
U2 23
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 434
EP 440
DI 10.1038/370434a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700048
PM 8047162
DA 2026-03-10
ER

PT J
AU VALEGARD, K
   MURRAY, JB
   STOCKLEY, PG
   STONEHOUSE, NJ
   LILJAS, L
AF VALEGARD, K
   MURRAY, JB
   STOCKLEY, PG
   STONEHOUSE, NJ
   LILJAS, L
TI CRYSTAL-STRUCTURE OF AN BACTERIOPHAGE-RNA COAT PROTEIN-OPERATOR COMPLEX
SO NATURE
LA English
DT Article
ID turnip crinkle virus; binding site; resolution; synthetase; oligoribonucleotides; recognition; mechanism; ms2
AB THE RNA bacteriophage MS2 is a convenient model system for the study-of protein-RNA interactions, The MS2 coat protein achieves control of two distinct processes-sequence-specific RNA encapsidation and repression of replicase translation-by binding to an RNA stem-loop structure of 19 nucleotides containing the initiation codon of the replicase gene. The binding of a coat protein diner to this hairpin shuts off synthesis of the viral replicase(1), switching the viral replication cycle to virion assembly rather than continued replication. The operator fragment alone can trigger self-assembly of the phage capsid at low protein concentrations and a complex of about 90 RNA operator fragments per protein capsid has been described(2). We report here the crystal structure at 3.0 Angstrom resolution of a complex between recombinant MS2 capsids and the 19-nucleotide RNA fragment. It is the first example of a structure at this resolution for a sequence-specific protein-RNA complex apart from the transfer RNA synthetase complexes(3-5). The structure shows sequence-specific interactions between conserved residues on the protein and RNA bases essential for binding.
C1 UNIV LEEDS, DEPT GENET, LEEDS LS2 9JT, W YORKSHIRE, ENGLAND.
C3 University of Leeds
RP VALEGARD, K (corresponding author), UPPSALA UNIV, DEPT MOLEC BIOL, BOX 590, S-75124 UPPSALA, SWEDEN.
FU Wellcome Trust Funding Source: Medline
NR 28
TC 348
Z9 390
U1 0
U2 37
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 623
EP 626
DI 10.1038/371623a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900057
PM 7523953
DA 2026-03-10
ER

PT J
AU FARBER, DL
   WILLIAMS, Q
   RYERSON, FJ
AF FARBER, DL
   WILLIAMS, Q
   RYERSON, FJ
TI DIFFUSION IN MG2SIO4 POLYMORPHS AND CHEMICAL HETEROGENEITY IN THE MANTLE TRANSITION ZONE
SO NATURE
LA English
DT Article
ID dislocation recovery; high-pressure; olivine; creep; mg; spinel
AB DIFFUSION in silicates plays a key role in a number of processes in the Earth's mantle, including viscous flow(1-4), electrical conductance(5-8) and the homogenization of chemical heterogeneities. Although cation diffusion rates have been measured in olivine at high pressures(9,10), no data exist on the chemical transport properties of the silicate phases thought to predominate in the transition zone of the mantle (from 400 to 700 km depth). Here we present measurements of cation diffusion in the alpha-olivine phase and high-pressure beta- and gamma-spinel phases of Mg2SiO4 at pressures up to 14 GPa. We find that diffusion rates in both high-pressure phases are about three orders of magnitude faster than that of olivine. When coupled with convective thinning, these faster diffusion rates suggest that the transition zone is more efficient at mixing chemical heterogeneities than the olivine-dominated upper mantle. Furthermore, we calculate that the minimum size of chemical heterogeneities in the transition zone should be of the order of metres.
C1 UNIV CALIF SANTA CRUZ,DEPT EARTH SCI,SANTA CRUZ,CA 95064.
   UNIV CALIF SANTA CRUZ,INST TECTON,SANTA CRUZ,CA 95064.
   LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94550.
C3 University of California System; University of California Santa Cruz; University of California System; University of California Santa Cruz; United States Department of Energy (DOE); Lawrence Livermore National Laboratory
NR 28
TC 35
Z9 39
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 693
EP 695
DI 10.1038/371693a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300052
DA 2026-03-10
ER

PT J
AU ZEHETNER, G
   LEHRACH, H
AF ZEHETNER, G
   LEHRACH, H
TI THE REFERENCE LIBRARY-SYSTEM - SHARING BIOLOGICAL-MATERIAL AND EXPERIMENTAL-DATA
SO NATURE
LA English
DT Article
ID density
RP ZEHETNER, G (corresponding author), IMPERIAL CANC RES FUND,GENOME ANAL LAB,POB 123,LONDON WC2A 3PX,ENGLAND.
NR 5
TC 121
Z9 124
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 489
EP 491
DI 10.1038/367489a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900063
PM 8107810
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI A SCIENTISTS HISTORY OF MEXICO
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 792
EP 792
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700025
DA 2026-03-10
ER

PT J
AU YAO, Z
   YOON, SW
   DAI, HJ
   FAN, SS
   LIEBER, CM
AF YAO, Z
   YOON, SW
   DAI, HJ
   FAN, SS
   LIEBER, CM
TI PATH OF MAGNETIC-FLUX LINES THROUGH HIGH-T-C COPPER-OXIDE SUPERCONDUCTORS
SO NATURE
LA English
DT Article
ID ii superconductor; lattices; yba2cu3o7; vortices; liquids; surface; films; array
AB A SERIOUS impediment to many potential applications of the high-transition-temperature (high-T-c) copper oxide superconductors is the relative ease with which magnetic flux lines move within these materials, thereby producing finite electrical resistance(1,2). To devise methods for rigidly fixing flux lines in these materials, which is necessary to achieve a truly superconducting (zero resistance) state, requires an understanding of their fundamental properties. In clean, conventional type II superconductors, flux lines or vortices can be modelled well as rigid objects that pass straight through a sample. In the high-T-c materials, however, comparatively short coherence lengths, large anisotropies and large accessible thermal energies lead to more complex and fascinating behaviour, giving for example entangled flux lines and two-dimensional pancake vortices(3-5). Some detail of the vortex lattice has been resolved previously(6-13), although it is not clear how vortices pass through these materials. Here we address this critical issue by simultaneously decorating the positions of flux lines at opposite sides of single-crystal Bi2Sr2CaCu2O8 (BSCCO) high-T-c superconductors using the Bitter technique(14,15). These new data enable us to quantify the wandering of vortices as they pass through the BSCCO high-T-c materials and address the elasticity of the vortex lattice. This information mill be useful for devising effective strategies for pinning flux lints to the crystal lattice.
C1 HARVARD UNIV,DIV APPL SCI,CAMBRIDGE,MA 02138.
   HARVARD UNIV,DEPT CHEM,CAMBRIDGE,MA 02138.
C3 Harvard University; Harvard University
NR 20
TC 35
Z9 36
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 777
EP 779
DI 10.1038/371777a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800052
DA 2026-03-10
ER

PT J
AU DEDHAR, S
   RENNIE, PS
   SHAGO, M
   HAGESTEIJN, CYL
   YANG, HL
   FILMUS, J
   HAWLEY, RG
   BRUCHOVSKY, N
   CHENG, H
   MATUSIK, RJ
   GIGUERE, V
AF DEDHAR, S
   RENNIE, PS
   SHAGO, M
   HAGESTEIJN, CYL
   YANG, HL
   FILMUS, J
   HAWLEY, RG
   BRUCHOVSKY, N
   CHENG, H
   MATUSIK, RJ
   GIGUERE, V
TI INHIBITION OF NUCLEAR HORMONE-RECEPTOR ACTIVITY BY CALRETICULIN
SO NATURE
LA English
DT Article
ID embryonal carcinoma-cells; ro/ss-a autoantigen; glucocorticoid receptor; molecular-cloning; binding protein; beta-tubulin; expression; induction; antigen; domain
AB WE have shown that a polypeptide of M(r) 60,000 (60K) that shares N-terminal homology with a calcium-binding protein, calreticulin, can bind to an amino-acid sequence motif, KXGFFKR, found in the cytoplasmic domains of all integrin alpha-subunits1. The homologous amino-acid sequence, KXFFKR (where X is either G, A or V), is also present in the DNA-binding domain of all known members of the steroid hormone receptor family2; amino acids in this sequence make direct contact with nucleotides in their DNA-responsive elements and are crucial for DNA binding3. Here we show that both the 60K protein (p60), purified on a KLGFFKR-Sepharose affinity matrix, and recombinant calreticulin can inhibit the binding of androgen receptor to its hormone-responsive DNA element in a KXFFKR-sequence-specific manner. Calreticulin can also inhibit androgen receptor and retinoic acid receptor transcriptional activities in vivo, as well as retinoic acid-induced neuronal differentiation. Our results indicate that calreticulin can act as an important modulator of the regulation of gene transcription by nuclear hormone receptors.
C1 UNIV TORONTO,SUNNYBROOK HLTH SCI CTR,DEPT MED BIOPHYS,TORONTO M4N 3M5,ON,CANADA.
   BRITISH CANC CANC AGCY,DEPT CANC ENDOCRINOL,VANCOUVER V5Z 4E6,BC,CANADA.
   UNIV TORONTO,HOSP SICK CHILDREN,DIV ENDOCRINE RES,TORONTO M5G 1X8,ONTARIO,CANADA.
   UNIV TORONTO,HOSP SICK CHILDREN,DEPT MOLEC & MED GENET,TORONTO M5G 1X8,ONTARIO,CANADA.
   UNIV MANITOBA,DEPT PHYSIOL,WINNIPEG R3E 0W3,MANITOBA,CANADA.
C3 University of Toronto; Sunnybrook Health Science Center; Sunnybrook Research Institute; University of Toronto; Hospital for Sick Children (SickKids); University of Toronto; Hospital for Sick Children (SickKids); University of Manitoba
RP DEDHAR, S (corresponding author), UNIV TORONTO,SUNNYBROOK HLTH SCI CTR,DIV CANC RES,REICHMANN RES BLDG,2075 BAYVIEW AVE,TORONTO M4N 3M5,ON,CANADA.
NR 25
TC 337
Z9 363
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 480
EP 483
DI 10.1038/367480a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900060
PM 8107809
DA 2026-03-10
ER

PT J
AU HARRIS, GC
   ASTONJONES, G
AF HARRIS, GC
   ASTONJONES, G
TI INVOLVEMENT OF D2 DOPAMINE-RECEPTORS IN THE NUCLEUS-ACCUMBENS IN THE OPIATE WITHDRAWAL SYNDROME
SO NATURE
LA English
DT Article
ID locus-coeruleus neurons; cyclic-amp formation; rat; morphine; clonidine; reward; specificity; projections; abstinence; inhibition
AB THE nucleus accumbens is prominently implicated in the reinforcing effects of abused drugs(1-4), and is an important site for mediating aversive stimulus properties of opiate withdrawal(5). It is generally thought, however, that the role of the accumbens is negligible in the somatic signs of opiate withdrawal(5-7). Contrary to this assumption, we now report that D2 dopaminergic receptor activity in the accumbens area potently regulates somatic symptoms of opiate withdrawal. We find that activation of D2 receptors within the accumbens prevents somatic signs of naloxone-induced opiate withdrawal and, conversely, that blockade of accumbal D2 receptors in opiate-dependent animals elicits somatic withdrawal symptoms. These data indicate that dopamine in the accumbens not only is important in the rewarding effects of abused drugs, but also (via D2 receptors) plays a pivotal role in opiate withdrawal.
C1 HAHNEMANN UNIV,DEPT MENTAL HLTH SCI,DIV BEHAV NEUROBIOL,PHILADELPHIA,PA 19102.
C3 Drexel University
NR 30
TC 193
Z9 213
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 155
EP 157
DI 10.1038/371155a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100063
PM 7915401
DA 2026-03-10
ER

PT J
AU TOUMI, R
   BEKKI, S
   LAW, KS
AF TOUMI, R
   BEKKI, S
   LAW, KS
TI INDIRECT INFLUENCE OF OZONE DEPLETION ON CLIMATE FORCING BY CLOUDS
SO NATURE
LA English
DT Article
ID trace gas budgets; condensation nuclei; atmospheric sulfur; tropospheric ozone; marine atmosphere; model; phytoplankton; chemistry; radicals; trends
AB CHEMICAL depletion of ozone in the lower stratosphere decreases the direct radiative forcing from greenhouse gases in the atmosphere(1). Here we show that ozone depletion may also exert an indirect effect on radiative forcing via its effect on the oxidation state of the atmosphere. Hydroxyl (OH) radicals in the troposphere are produced by photodissociation of tropospheric ozone in the presence of water vapour, and this process is enhanced if the absorption of ultraviolet radiation by the overlying stratospheric ozone column decreases. As OH oxidizes SO2 to sulphuric acid, which then forms cloud condensation nuclei(2), variations in tropospheric OH concentration can influence cloud albedo. We use a global two-dimensional model forced by observed changes in stratospheric ozone to calculate the consequent changes in production of sulphuric acid over the past decade, and thus to estimate the effect on cloud albedo. We find that this indirect effect of ozone depletion may decrease radiative forcing (via increased cloud reflectivity) by at least as much as the direct effect.
C1 UNIV CAMBRIDGE,CTR ATMOSPHER SCI,DEPT CHEM,CAMBRIDGE CB2 1EW,ENGLAND.
C3 University of Cambridge
RP TOUMI, R (corresponding author), UNIV LONDON IMPERIAL COLL SCI & TECHNOL,DEPT PHYS,LONDON SW7 2BZ,ENGLAND.
NR 30
TC 34
Z9 37
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 348
EP 351
DI 10.1038/372348a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700050
DA 2026-03-10
ER

PT J
AU GELPERIN, A
AF GELPERIN, A
TI NITRIC-OXIDE MEDIATES NETWORK OSCILLATIONS OF OLFACTORY INTERNEURONS IN A TERRESTRIAL MOLLUSK
SO NATURE
LA English
DT Article
ID activation; messenger; synthase; release; brain; rat
AB THE interneuronal messenger nitric oxide(1,2) (NO) may play a central role in the processing of olfactory information(3). Several circuit elements in the mammalian olfactory bulb contain NO synthase(4) or its functional equivalent, NADPH diaphorase(5-7). The effects of NO on cellular,excitability or circuit dynamics in the olfactory bulb are unknown, although NO effects on other rhythmic cells(8) and circuits(9) have been described. T have studied the role of NO in central olfactory processing using the procerebral (PC) lobe, the major central site of odour processing in terrestrial molluscs(10,11). As in the mammalian olfactory bulb during odour stimulation, the basic dynamics of electrical activity in the molluscan PC lobe is an oscillation(12-14). Here I report an obligatory role for NO is the oscillatory dynamics of the PC lobe of Limax maximus. Nitric oxide mediation of the olfactory oscillation may relate to the highly developed odour sensitivity and odour-learning ability of Limax(15,16).
RP GELPERIN, A (corresponding author), AT&T BELL LABS,BIOL COMPUTAT RES DEPT,600 MT AVE,MURRAY HILL,NJ 07974, USA.
NR 28
TC 204
Z9 207
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 61
EP 63
DI 10.1038/369061a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000053
PM 8164740
DA 2026-03-10
ER

PT J
AU PATEL, NH
   CONDRON, BG
   ZINN, K
AF PATEL, NH
   CONDRON, BG
   ZINN, K
TI PAIR-RULE EXPRESSION PATTERNS OF EVEN-SKIPPED ARE FOUND IN BOTH SHORT-GERM AND LONG-GERM BEETLES
SO NATURE
LA English
DT Article
ID drosophila-melanogaster; embryonic pattern; homeo box; gene; segmentation; localization; transcripts; polarity; protein
AB Now that the genes controlling embryonic patterning have been identified in several model organisms, long-standing questions concerning the evolution of developmental systems are open to investigation. Examination of the expression of even-skipped in a variety of insects reveals that insect germ-type designations apparently do not reflect the variations in the mechanisms of segmentation evident throughout insect phylogeny.
C1 CALTECH,DIV BIOL,PASADENA,CA 91125.
C3 California Institute of Technology
RP PATEL, NH (corresponding author), CARNEGIE INST WASHINGTON,DEPT EMBRYOL,115 W UNIV PKWY,BALTIMORE,MD 21210, USA.
NR 28
TC 247
Z9 266
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 429
EP 434
DI 10.1038/367429a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900045
PM 8107801
DA 2026-03-10
ER

PT J
AU AQUILANTI, V
   ASCENZI, D
   CAPPELLETTI, D
   PIRANI, F
AF AQUILANTI, V
   ASCENZI, D
   CAPPELLETTI, D
   PIRANI, F
TI VELOCITY DEPENDENCE OF COLLISIONAL ALIGNMENT OF OXYGEN MOLECULES IN GASEOUS EXPANSIONS
SO NATURE
LA English
DT Article
ID lowest excited-states; open-shell systems; weak-interactions; rotational temperature; beam; scattering; dynamics; atoms; orientation; chlorine
AB THE orientational dependence of molecular interactions has long been recognized as central to an understanding of reaction mechanisms and of collisions in the gas phase and at surfaces. Studies of orientation effects have recently become possible owing to the development of techniques for aligning molecules. 'Brute-force' methods using electric or magnetic fields can induce alignment of molecules with dipole moments(1,2), and polarized-absorption approaches(3) can be used in cases where there are suitable molecular transitions; but one of the simplest and most general methods involves the supersonic expansion of molecular beams seeded with molecules that induce rotational alignment-selection of specific rotational states-by collisions(4-12). Here we use such an approach to induce strong rotational alignment of oxygen molecules in a beam seeded with various other gases at close to atmospheric pressure. Most significantly, we find that the degree of alignment depends on the velocity of the molecules in the supersonic expansion-fast molecules are much more highly aligned than slower ones, and the velocity of maximum alignment can be altered by changing the gas mixture. In this way, we can prepare rotationally aligned molecules with well defined velocities, opening up new possibilities for experiments in molecular dynamics.
RP AQUILANTI, V (corresponding author), UNIV PERUGIA,DIPARTIMENTO CHIM,I-06100 PERUGIA,ITALY.
NR 31
TC 147
Z9 150
U1 0
U2 28
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 399
EP 402
DI 10.1038/371399a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500036
DA 2026-03-10
ER

PT J
AU IVINSON, AJ
AF IVINSON, AJ
TI RIGHTING AN INHERITED WRONG
SO NATURE
LA English
DT Article
NR 9
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 665
EP 665
DI 10.1038/368665a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200071
DA 2026-03-10
ER

PT J
AU YU, P
   KOSCOVILBOIS, M
   RICHARDS, M
   KOHLER, G
   LAMERS, MC
AF YU, P
   KOSCOVILBOIS, M
   RICHARDS, M
   KOHLER, G
   LAMERS, MC
TI NEGATIVE FEEDBACK-REGULATION OF IGE SYNTHESIS BY MURINE CD23
SO NATURE
LA English
DT Article
ID low-affinity receptor; fc-epsilon-rii; b-cells; t-cells; fc-epsilon-rii/cd23; lymphocytes; inhibition; activation; responses; clones
AB IMMUNOGLOBULIN E is found in nanogram amounts in normal human and mouse serum. It is increased during parasitic infestations(1) and mediates allergy. CD23, the low-affinity receptor for IgE (Fc epsilon RII), has been proposed as an important regulator of IgE synthesis(2-4). The type-II transmembrane lectin(4) CD23 is expressed in the mouse on B cells and follicular dendritic cells. In humans there are two forms of CD23 which differ in their intracellular amino-terminal 6/7 amino acids(4); expression of the A-form corresponds to that of murine CD23, whereas the B-form is also found on T and other haematopoietic cells(4). CD23 has been implicated in cellular adhesion(5), antigen presentation(6), as a growth and differentiation factor for human B, T and plasma cells, and as a signal transduction molecule(7) (reviewed in refs 3, 8). Here we disrupt the gene coding for murine CD23 (ref. 9) to clarify the role of CD23 in vivo and find that B- and T-cell development is normal in these CD23-deficient mice. Immune responses to the helminth Nippostrongylus brasiliensis are unaffected, In contrast, immunization with thymus-dependent antigens leads to increased and sustained specific IgE antibody titres compared with controls. Formation of germinal centres is normal. These results suggest that murine CD23 acts as a negative feedback component of IgE regulation.
C1 MAX PLANCK INST IMMUNBIOL,D-79108 FREIBURG,GERMANY.
   BASEL INST IMMUNOL,CH-4005 BASEL,SWITZERLAND.
   MED BIOL INST,LA JOLLA,CA 92037.
C3 Max Planck Society
NR 29
TC 210
Z9 236
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 753
EP 756
DI 10.1038/369753a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100063
PM 8008068
DA 2026-03-10
ER

PT J
AU ALBERT, MS
   CATES, GD
   DRIEHUYS, B
   HAPPER, W
   SAAM, B
   SPRINGER, CS
   WISHNIA, A
AF ALBERT, MS
   CATES, GD
   DRIEHUYS, B
   HAPPER, W
   SAAM, B
   SPRINGER, CS
   WISHNIA, A
TI BIOLOGICAL MAGNETIC-RESONANCE-IMAGING USING LASER POLARIZED XE-129
SO NATURE
LA English
DT Article
ID nuclear-spin relaxation; projection reconstruction; xenon; gas; exchange; nmr; solubility; liquids; brain
AB AS currently implemented, magnetic resonance imaging (MRI) relies on the protons of water molecules in tissue to provide the NMR signal. Protons are, however, notoriously difficult to image in some biological environments of interest, notably the lungs(1) and lipid bilayer membranes such as those in the brain(2). Here we show that Xe-129 gas can be used for high-resolution MRI when the nuclear-spin polarization of the atoms is increased by laser optical pumping and spin exchange(3-6). This process produces hyperpolarized Xe-129, in which the magnetization is enhanced by a factor of about 10(5). By introducing hyperpolarized Xe-129 into mouse lungs we have obtained images of the lung gas space with a speed and a resolution better than those available from proton MRI(1,7) or emission tomography(8,9). As xenon (a safe general anaesthetic) is rapidly-and safely transferred from the lungs to blood and thence to other tissues(8,9), where it is concentrated in lipid(10-15) and protein(13,15-18) components, images of the circulatory system, the brain and other vital organs can also be obtained. Because the magnetic behaviour of Xe-129 is very sensitive to its environment, and is different from that of (H2O)-H-1, MRI using hyperpolarized Xe-129 should involve distinct and sensitive mechanisms for tissue contrast.
C1 PRINCETON UNIV,DEPT PHYS,PRINCETON,NJ 08544.
C3 Princeton University
RP ALBERT, MS (corresponding author), SUNY STONY BROOK,DEPT CHEM,STONY BROOK,NY 11794, USA.
NR 32
TC 893
Z9 1040
U1 4
U2 177
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 199
EP 201
DI 10.1038/370199a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100045
PM 8028666
DA 2026-03-10
ER

PT J
AU MA, JY
   YEE, A
   BREWER, HB
   DAS, S
   POTTER, H
AF MA, JY
   YEE, A
   BREWER, HB
   DAS, S
   POTTER, H
TI AMYLOID-ASSOCIATED PROTEINS ALPHA(1)-ANTICHYMOTRYPSIN AND APOLIPOPROTEIN-E PROMOTE ASSEMBLY OF ALZHEIMER BETA-PROTEIN INTO FILAMENTS
SO NATURE
LA English
DT Article
ID inhibitor alpha-1-antichymotrypsin; type-4 allele; disease; peptide; deposits; binding; invitro; metabolism; fibrils; plaque
AB THE protease inhibitor alpha(1)-antichymotrypsin and the lipid transport protein apolipoprotein E (apoE) are intimately associated with the 42-amino-acid beta-peptide (A beta) in the filamentous amyloid deposits of Alzheimer's disease(1-3). We report here that these two amyloid-associated proteins serve a strong stimulatory role in the polymerization of A beta into amyloid filaments. Addition of either alpha(1)-antichymotrypsin or apoE to the A beta peptide promoted a 10- to 20-fold increase in filament formation, with apoE-4, the isoform recently linked to the development of late-onset Alzheimer's disease, showing the highest catalytic activity. These and other experiments suggest that Alzheimer amyloid deposits arise when A beta is induced to form filaments by amyloid-promoting factors (pathological chaperones) expressed in certain brain regions.
C1 NHLBI,BETHESDA,MD 20892.
   HARVARD UNIV,SCH MED,DEPT NEUROBIOL,BOSTON,MA 02115.
C3 National Institutes of Health (NIH) - USA; NIH National Heart Lung & Blood Institute (NHLBI); Harvard University; Harvard Medical School
NR 31
TC 866
Z9 939
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 92
EP 94
DI 10.1038/372092a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800079
PM 7969426
DA 2026-03-10
ER

PT J
AU ENQUIST, M
   ARAK, A
AF ENQUIST, M
   ARAK, A
TI SYMMETRY, BEAUTY AND EVOLUTION
SO NATURE
LA English
DT Article
AB HUMANS and certain other species find symmetrical patterns more attractive than asymmetrical ones. These preferences may appear in response to biological signals(1-3), or in situations where there is no obvious signalling context, such as exploratory behaviour(4,5) and human aesthetic response to pattern(6-8). It has been proposed(9,10) that preferences for symmetry have evolved in animals because the degree of symmetry in signals indicates the signaller's quality. By contrast, we show here that symmetry preferences may arise as a by-product of the need to recognize objects irrespective of their position and orientation in the visual field. The existence of sensory biases for symmetry may have been exploited independently by natural selection acting on biological signals and by human artistic innovation. This may account for the observed convergence on symmetrical forms in nature and decorative art(11).
C1 ARCHWAY ENGN UK LTD,ELLAND HX5 9JP,W YORKSHIRE,ENGLAND.
RP ENQUIST, M (corresponding author), UNIV STOCKHOLM,DEPT ZOOL,S-10691 STOCKHOLM,SWEDEN.
NR 25
TC 337
Z9 384
U1 3
U2 104
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 169
EP 172
DI 10.1038/372169a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800053
PM 7969448
DA 2026-03-10
ER

PT J
AU BURMEISTER, WP
   GASTINEL, LN
   SIMISTER, NE
   BLUM, ML
   BJORKMAN, PJ
AF BURMEISTER, WP
   GASTINEL, LN
   SIMISTER, NE
   BLUM, ML
   BJORKMAN, PJ
TI CRYSTAL-STRUCTURE AT 2.2-ANGSTROM RESOLUTION OF THE MHC-RELATED NEONATAL FC RECEPTOR
SO NATURE
LA English
DT Article
ID class-i h-2k(b); histocompatibility antigen; 3-dimensional structure; peptide antigens; small-intestine; binding; complex; recognition; hla-a2; rat
AB The three-dimensional structure of the rat neonatal Fe receptor (FcRn) is similar to the structure of molecules of the major histocompatibility complex (MHC). The counterpart of the MHC peptide-binding site is closed in FcRn, making the FcRn groove incapable of binding peptides. A dimer of FcRn heterodimers seen in the crystals may represent a receptor dimer that forms when the Fc portion of a single immunoglobulin binds. An alternative use of the MHC fold for immune recognition is indicated by the FcRn and FcRn/Fc co-crystal structures.
C1 CALTECH,DEPT BIOL,PASADENA,CA 91125.
   CALTECH,HOWARD HUGHES MED INST,PASADENA,CA 91125.
   BRANDEIS UNIV,DEPT BIOL,WALTHAM,MA 02254.
   BRANDEIS UNIV,ROSENSTIEL BASIC MED SCI RES CTR,WALTHAM,MA 02254.
C3 California Institute of Technology; California Institute of Technology; Howard Hughes Medical Institute; Brandeis University; Brandeis University
NR 50
TC 292
Z9 347
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 336
EP 343
DI 10.1038/372336a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700047
PM 7969491
DA 2026-03-10
ER

PT J
AU LOVLEY, DR
   WOODWARD, JC
   CHAPELLE, FH
AF LOVLEY, DR
   WOODWARD, JC
   CHAPELLE, FH
TI STIMULATED ANOXIC BIODEGRADATION OF AROMATIC-HYDROCARBONS USING FE(III) LIGANDS
SO NATURE
LA English
DT Article
ID denitrifying conditions; aquifer microorganisms; dissimilatory fe(iii); microbial-degradation; organic contaminants; reducing conditions; hydrogen-peroxide; iron reduction; shallow sand; groundwater
AB CONTAMINATION of ground waters with water-soluble aromatic hydrocarbons, common components of petroleum pollution, often produces anoxic conditions under which microbial degradation of the aromatics is slow(1-7). Oxygen is often added to contaminated ground water to stimulate biodegradation, but this can be technically difficult and expensive(1,5-8). Insoluble Fe(III) oxides, which are generally abundant in shallow aquifers, are alternative potential oxidants, but are difficult for microorganisms to access(9). Here we report that adding organic ligands that bind to Fe(III) dramatically increases its bioavailability, and that in tbe presence of these ligands, rates of degradation of aromatic hydrocarbons in anoxic aquifer sediments are comparable to those in oxic sediments. We find that even benzene, which is notoriously refractory in the absence of oxygen, can be rapidly degraded. Our results suggest that increasing the bioavailability of Fe(III) by adding suitable ligands provides a potential alternative to oxygen addition for the bioremediation of petroleum-contaminated aquifers.
C1 US GEOL SURVEY, DIV WATER RESOURCES, COLUMBIA, SC 29210 USA.
C3 United States Department of the Interior; United States Geological Survey
RP LOVLEY, DR (corresponding author), US GEOL SURVEY, DIV WATER RESOURCES, 430 NATL CTR, RESTON, VA 22092 USA.
NR 28
TC 260
Z9 306
U1 2
U2 127
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 128
EP 131
DI 10.1038/370128a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400052
PM 8022480
DA 2026-03-10
ER

PT J
AU CLAYTON, DD
AF CLAYTON, DD
TI PRODUCTION OF AL-26 AND OTHER EXTINCT RADIONUCLIDES BY LOW-ENERGY HEAVY COSMIC-RAYS IN MOLECULAR CLOUDS
SO NATURE
LA English
DT Article
ID early solar-system; particle interactions; o-16
AB THE high abundance of radioactive Al-26 in meteoritic materials(1) presents a puzzle in attempts to describe the formation of the Solar System. It has been suggested(11) that collapse of the solar nebula may have been accompanied by an injection of Al-26 from nucleosynthesis in a neighbouring star. The relatively high level of Al-26 in the interstellar medium (2,3) is also unexplained. Here I suggest that this isotope may be formed in nuclear reactions between hydrogen and heavy cosmic rays. This suggestion is prompted by the recent discovery(4) of gamma-ray line emission from C-12 and O-16 in the Orion cloud complex, thought to be caused by the interaction of these cosmic-ray ions with interstellar hydrogen. I show that these observations also imply enhanced production of Al-26 in the Orion molecular clouds, and that such nuclear reactions can account for the meteoritic abundances. Reactions involving heavy cosmic rays might also account for the presence of other extinct radioactive nuclides in meteorites.
RP CLAYTON, DD (corresponding author), CLEMSON UNIV,DEPT PHYS & ASTRON,CLEMSON,SC 29634, USA.
NR 24
TC 53
Z9 54
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 222
EP 224
DI 10.1038/368222a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000047
DA 2026-03-10
ER

PT J
AU BRAIG, K
   OTWINOWSKI, Z
   HEGDE, R
   BOISVERT, DC
   JOACHIMIAK, A
   HORWICH, AL
   SIGLER, PB
AF BRAIG, K
   OTWINOWSKI, Z
   HEGDE, R
   BOISVERT, DC
   JOACHIMIAK, A
   HORWICH, AL
   SIGLER, PB
TI THE CRYSTAL-STRUCTURE OF THE BACTERIAL CHAPERONIN GROEL AT 2.8-ANGSTROM
SO NATURE
LA English
DT Article
ID escherichia-coli groel; molecular chaperone; heat-shock; protein models; central cavity; hydrolysis; interfaces; surface; errors; cycle
AB The crystal structure of Escherichia coli GroEL shows a porous cylinder of 14 subunits made of two nearly 7-fold rotationally symmetrical rings stacked back-to-back with dyad symmetry. The subunits consist of three domains: a targe equatorial domain that forms the foundation of the assembly at its waist and holds the rings together; a large loosely structured apical domain that forms the ends of the cylinder; and a small slender intermediate domain that connects the two, creating side windows. The three-dimensional structure places most of the mutationally defined functional sites on the channel walls and its outward invaginations, and at the ends of the cylinder.
C1 YALE UNIV,SCH MED,BOYER CTR,HOWARD HUGHES MED INST,NEW HAVEN,CT 06510.
   YALE UNIV,SCH MED,DEPT GENET,NEW HAVEN,CT 06510.
   YALE UNIV,SCH MED,DEPT MOLEC BIOPHYS & BIOCHEM,NEW HAVEN,CT 06510.
C3 Yale University; Howard Hughes Medical Institute; Yale University; Yale University
NR 52
TC 1226
Z9 1331
U1 1
U2 77
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 578
EP 586
DI 10.1038/371578a0
PG 9
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900043
PM 7935790
DA 2026-03-10
ER

PT J
AU LEHMAN, W
   CRAIG, R
   VIBERT, P
AF LEHMAN, W
   CRAIG, R
   VIBERT, P
TI CA2+-INDUCED TROPOMYOSIN MOVEMENT IN LIMULUS THIN-FILAMENTS REVEALED BY 3-DIMENSIONAL RECONSTRUCTION
SO NATURE
LA English
DT Article
ID electron-microscopy; muscle; troponin; actin; myosin; binding
AB THE steric model of muscle regulation holds that tropomyosin strands running along thin filaments move away from myosin-binding sites on actin when muscle is activated. Exposing these sites would permit actomyosin interaction and contraction to proceed. This compelling and widely cited model is based on changes observed in X-ray diffraction patterns of skeletal muscle following activation(1-3) Although analysis of X-ray patterns can suggest models of filament structure, unambiguous interpretation is not possible. In contrast, three-dimensional reconstruction of thin-filament electron micrographs could, in principle, offer direct confirmation of the predicted tropomyosin movement, but so far tropomyosin in skeletal muscle has been resolved definitively only in the 'on' state but not in the 'off' state(4). Thin filaments from the arthropod Limulus have a similar composition to those from vertebrate skeletal muscle(5), and troponin-tropomyosin is distributed in both species with the same characteristic 38-nm periodicity(6) Limulus thin filaments activate skeletal muscle myosin ATPase at micromolar Ca2+ concentrations and confer a high calcium dependence on the enzyme. Arthropod and vertebrate troponin subunits form functional hybrids in vitro(7) and the respective tropomyosins are functionally interchangeable(8,9), arguing for a common mechanism of thin-filament-linked regulation in the two phyla. Here we report that tropomyosin is readily resolved in native filaments of troponin-regulated Limulus muscle in both the 'on' and 'off' states, and demonstrate tropomyosin movement, providing support for the importance of steric effects in muscle activation.
C1 UNIV MASSACHUSETTS,SCH MED,DEPT CELL BIOL,WORCESTER,MA 01655.
   BRANDEIS UNIV,ROSENSTIEL BASIC MED SCI RES CTR,WALTHAM,MA 02254.
C3 University of Massachusetts System; University of Massachusetts Worcester; Brandeis University
RP LEHMAN, W (corresponding author), BOSTON UNIV,SCH MED,DEPT PHYSIOL,80 E CONCORD ST,BOSTON,MA 02118, USA.
NR 25
TC 299
Z9 350
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 65
EP 67
DI 10.1038/368065a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900054
PM 8107884
DA 2026-03-10
ER

PT J
AU KUWATA-GONOKAMI, M
   PEYGHAMBARIAN, N
   MEISSNER, K
   FLUEGEL, B
   SATO, Y
   EMA, K
   SHIMANO, R
   MAZUMDAR, S
   GUO, F
   TOKIHIRO, T
   EZAKI, H
   HANAMURA, E
AF KUWATA-GONOKAMI, M
   PEYGHAMBARIAN, N
   MEISSNER, K
   FLUEGEL, B
   SATO, Y
   EMA, K
   SHIMANO, R
   MAZUMDAR, S
   GUO, F
   TOKIHIRO, T
   EZAKI, H
   HANAMURA, E
TI EXCITON STRINGS IN AN ORGANIC CHARGE-TRANSFER CRYSTAL
SO NATURE
LA English
DT Article
ID chloranil
AB COLLECTIVE excitations resulting from many-body Coulomb interactions have been studied extensively in the solid state1: for example, the exchange interaction between the electrons in two excitons (bound electron-hole pairs) can bind the excitons together, forming a biexciton. At the other extreme, if the number of excitons is sufficiently large (approximately 10(6)), they can condense into a degenerate 'liquid' phase known as an electron-hole drop. But in conventional semiconductors, intermediate bound states, consisting of more than two excitons, are not formed. We show here, both theoretically and experimentally, that bound states of multiple excitons can form in the organic charge-transfer solid anthracene-(pyromellitic acid dianhydride). Coulomb interactions along the one-dimensional stacks of this material can stabilize trains of several charge-transfer excitons, and we refer to the resulting collective excitations as exciton strings.
C1 UNIV ARIZONA, DEPT PHYS, TUCSON, AZ 85721 USA.
   UNIV ARIZONA, CTR OPT SCI, TUCSON, AZ 85724 USA.
C3 University of Arizona; University of Arizona
RP KUWATA-GONOKAMI, M (corresponding author), UNIV TOKYO, DEPT APPL PHYS, TOKYO 113, JAPAN.
NR 7
TC 89
Z9 93
U1 0
U2 28
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 47
EP 48
DI 10.1038/367047a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500052
DA 2026-03-10
ER

PT J
AU KOZONO, H
   WHITE, J
   CLEMENTS, J
   MARRACK, P
   KAPPLER, J
AF KOZONO, H
   WHITE, J
   CLEMENTS, J
   MARRACK, P
   KAPPLER, J
TI PRODUCTION OF SOLUBLE MHC CLASS-II PROTEINS WITH COVALENTLY BOUND SINGLE PEPTIDES
SO NATURE
LA English
DT Article
ID t-cell hybridomas; transgenic mice; antigen; recognition; thymocytes; complex; cd8; molecules; selection; tolerance
AB THE alpha beta T-cell receptors (TCRs) react with complex ligands composed of peptides bound to major histocompatibility complex (MHC) proteins. In the absence of foreign antigens the peptides bound to MHC molecules come from the proteins of the host itself(1-5). Interactions between TCRs and these self-peptide-MHC ligands work positively to drive T-cell development in the thymus(6-9) and negatively to delete or inactivate T cells with potential self-reactivity(10-12). On the cell surface, MHC proteins are associated with many different self peptides, making it impossible to know which self peptide was involved in positive or negative interactions with a particular T cell. These studies as well as in vitro studies on TCR-peptide-MHC interactions would be aided by a means of producing MHC molecules containing a single peptide. We have tackled this problem for MHC class II proteins by genetically attaching the peptide by a flexible peptide linker to the amino terminus of the class II beta-chain. Here we report that a secreted, soluble form of this covalent peptide-MHC complex can be expressed in insect cells. The peptide is engaged by the peptide-binding groove of the secreted MHC molecule and this complex is recognized by T cells bearing receptors specific for that combination.
C1 UNIV COLORADO,HLTH SCI CTR,DEPT IMMUNOL,DENVER,CO 80206.
   UNIV COLORADO,HLTH SCI CTR,DEPT BIOPHYS,DENVER,CO 80206.
   UNIV COLORADO,HLTH SCI CTR,DEPT BIOCHEM,DENVER,CO 80206.
   UNIV COLORADO,HLTH SCI CTR,DEPT GENET,DENVER,CO 80206.
   UNIV COLORADO,HLTH SCI CTR,DEPT MED,DENVER,CO 80206.
C3 University of Colorado System; University of Colorado Anschutz Medical Campus; University of Colorado Denver; University of Colorado System; University of Colorado Anschutz Medical Campus; University of Colorado Denver; University of Colorado System; University of Colorado Denver; University of Colorado Anschutz Medical Campus; University of Colorado System; University of Colorado Anschutz Medical Campus; University of Colorado Denver; University of Colorado System; University of Colorado Anschutz Medical Campus; University of Colorado Denver
RP KOZONO, H (corresponding author), NATL JEWISH CTR IMMUNOL & RESP MED,HOWARD HUGHES MED INST,DEPT MED,DENVER,CO 80206, USA.
NR 25
TC 274
Z9 337
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 151
EP 154
DI 10.1038/369151a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100050
PM 8177320
DA 2026-03-10
ER

PT J
AU MAFRANETO, A
   CARDE, RT
AF MAFRANETO, A
   CARDE, RT
TI FINE-SCALE STRUCTURE OF PHEROMONE PLUMES MODULATES UPWIND ORIENTATION OF FLYING MOTHS
SO NATURE
LA English
DT Article
ID sex-pheromone; flight behavior; wind-tunnel; odor; lepidoptera; insects
AB IN studies of moths flying upwind to a pheromone source, attention has focused on the influence on flight orientation of the composition(1,2) and concentration(3,4) of the chemical message, and of changes in the visual environment(5,6) and in wind speeds(7-9). The chemical signal must be intermittent for moths to fly upwind(10-12), when they usually follow a zigzag track, the evident expression of a self-steered counterturning programme(13,14). The integration of counterturning and optomotor anemotaxis allows insects to polarize the zigzags upwind in odour plumes(10,15). Not all moths, however, zigzag along a plume(16,17). It has been suggested that the propensity to zigzag or to fly straight upwind is related to the frequency at which males encounter pheromone filaments that comprise the plume, as well as the male's latency of response, characteristic for each moth species, to both the onset and loss of contact with filaments(18). Here we present evidence that flight manoeuvres are dictated by the interactions of the male with individual odour pulses. We use Cadra cautella, the almond moth, to show how the structure of an odour plume(19,20) can greatly modify the flight track. Males following either turbulent or mechanically pulsed plumes fly faster and straighter upwind, and locate sources more frequently than males following continuous narrow plumes. Males also fly straighter upwind to fast-pulsed plumes than to slow-pulsed plumes. The temporally modulated interplay between counterturning and optomotor anemotaxis that is induced by the plume's structure therefore seems to explain the manoeuvres and resultant flight track shapes made by C. cautella males when flying upwind towards a pheromone source.
C1 UNIV MASSACHUSETTS,DEPT ENTOMOL,AMHERST,MA 01003.
C3 University of Massachusetts System; University of Massachusetts Amherst
NR 24
TC 331
Z9 372
U1 2
U2 42
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 142
EP 144
DI 10.1038/369142a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100047
DA 2026-03-10
ER

PT J
AU MILLER, JD
   BERNSTEIN, HD
   WALTER, P
AF MILLER, JD
   BERNSTEIN, HD
   WALTER, P
TI INTERACTION OF ESCHERICHIA-COLI FFH/4.5S RIBONUCLEOPROTEIN AND FTSY MIMICS THAT OF MAMMALIAN SIGNAL RECOGNITION PARTICLE AND ITS RECEPTOR
SO NATURE
LA English
DT Article
ID escherichia-coli; protein secretion; saccharomyces-cerevisiae; endoplasmic-reticulum; sequence recognition; nascent preprolactin; translocation; polypeptide; membrane
AB THE mechanism of-protein translocation across the endoplasmic reticulum membrane of eukaryotic cells and the plasma membrane of prokaryotic cells are thought to be evolutionarily related(1-7). Protein targeting to the eukaryotic translocation apparatus is mediated by the signal recognition particle (SRP), a cytosolic ribonucleoprotein, and the SRP receptor, an endoplasmic reticulum membrane protein(8,9). During targeting, the 54K SRP subunit (M(r), 54,000; SRP54), a GTP-binding protein(10-12), binds to signal sequences(13,14) and then interacts with the alpha-subunit of the SRP receptor (SR alpha), another GTP-binding protein(12,15). Two proteins from Escherichia coli, Ffh and FtsY, structurally resemble SRP54 and SR alpha(10,11,16). Like SRP54, Ffh is a subunit of a cytosolic ribonucleoprotein that also contains the E. coli 4.5S RNA(17,18). Although there is genetic and biochemical evidence that the E. coli Ffh/ 4.5S ribonucleoprotein has an SRP-like function(19-21), there is no evidence for an SR alpha-like role for FtsY. Here we show that the Ffh/ 4.5S ribonucleoprotein binds tightly to FtsY in a GTP-dependent manner. This interaction results in the stimulation of GTP hydrolysis which can be inhibited by synthetic signal peptides. These properties mimic those of mammalian SRP and its receptor, suggesting that the E. coli Ffh/4.5S ribonucleoprotein and FtsY have functions in protein targeting that are similar to those of their mammalian counterparts.
C1 UNIV CALIF SAN FRANCISCO,SCH MED,DEPT BIOCHEM & BIOPHYS,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco
NR 27
TC 159
Z9 186
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 657
EP 659
DI 10.1038/367657a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800058
PM 8107852
DA 2026-03-10
ER

PT J
AU SUZUKI, M
   TAKAHASHI, K
   IKEDA, M
   HAYAKAWA, H
   OGAWA, A
   KAWAGUCHI, Y
   SAKAI, O
AF SUZUKI, M
   TAKAHASHI, K
   IKEDA, M
   HAYAKAWA, H
   OGAWA, A
   KAWAGUCHI, Y
   SAKAI, O
TI CLONING OF A PH-SENSITIVE K+ CHANNEL POSSESSING 2 TRANSMEMBRANE SEGMENTS
SO NATURE
LA English
DT Article
ID potassium channels; tea blockade; drosophila; shaker; modulation; component; calcium; tubule; locus; brain
AB THE mammalian renal collecting ducts are responsible for secreting potassium ions into the urine and are a major regulatory site for potassium homeostasis(1), in which a voltage-independent pH-sensitive K+ channel in the apical membrane plays a central role(2,3). Here we describe a complementary DNA encoding a novel K+ channel from rabbit renal cortical collecting tubule cells (RACTK1). RACTK1 has the functional characteristics of the apical K+-permeable channel and consists of 284 amino acids, putatively with two transmembrane segments. The sequence of RACTK1, however, shows no homology to known voltage-dependent or -independent K+ channels, and has a different K+-driving path and regulatory sites, The study of this protein should provide insight into K+ homeostasis and diseases of K+ metabolism.
C1 JIKEIKAI UNIV, SCH MED, MINATO KU, TOKYO, TOKYO 105, JAPAN.
C3 Jikei University
RP SUZUKI, M (corresponding author), JICHI MED SCH, DEPT PHARMACOL, 3311-1 MINAMIKAWACHI, KAWACHI, TOCHIGI 32904, JAPAN.
NR 28
TC 68
Z9 69
U1 0
U2 1
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 642
EP 645
DI 10.1038/367642a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800053
PM 8107848
DA 2026-03-10
ER

PT J
AU LEE, HS
   HUANG, SS
   KAO, TH
AF LEE, HS
   HUANG, SS
   KAO, TH
TI S-PROTEINS CONTROL REJECTION OF INCOMPATIBLE POLLEN IN PETUNIA-INFLATA
SO NATURE
LA English
DT Article
ID self-incompatibility; nicotiana-alata; ribonuclease-activity; alleles; expression; hybrida
AB FLOWERING plants have evolved various stratagems to prevent inbreeding and promote outcrosses1. One such mechanism, gametophytic self-incompatibility, provides a genetic barrier to self-fertilization, and in the simplest cases is controlled by the highly polymorphic S locus2. Growth of a pollen tube in the style is arrested when the S allele carried by the pollen matches one of the two S alleles carried by the pistil. Putative S allele proteins of the pistil have been identified in several solanaceous species based on their co-segregation with S alleles3-12, and they have been shown to be ribonucleases13-15. So far. there has been only correlative or indirect evidence for the claim that these S allele-associated proteins (S proteins) are involved in recognition and rejection of self pollen16,17. Here we show that inhibition of synthesis of S3 and S2 proteins in Petunia inflata plants of S2S3 genotype by the antisense S3 gene resulted in failure of the transgenic plants to reject S3 and S2 pollen.  We further show that expression of the transgene encoding S3 protein in P. inflata plants of S1S2 genotype confers on the transgenic plants the ability to reject S3 pollen.  The self-incompatibility behaviour of the pollen was not affected by the transgene in either set of experiments.  Taken together, these findings provide direct in vivo evidence that S proteins control the self-incompatibility behaviour of the pistil.
C1 PENN STATE UNIV,DEPT BIOCHEM & MOLEC BIOL,UNIV PK,PA 16802.
   PENN STATE UNIV,CTR GENE REGULAT,UNIV PK,PA 16802.
C3 Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
NR 25
TC 345
Z9 413
U1 2
U2 64
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 560
EP 563
DI 10.1038/367560a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300059
PM 7509041
DA 2026-03-10
ER

PT J
AU BEARD, KC
   QI, T
   DAWSON, MR
   WANG, BY
   LI, CK
AF BEARD, KC
   QI, T
   DAWSON, MR
   WANG, BY
   LI, CK
TI A DIVERSE NEW PRIMATE FAUNA FROM MIDDLE EOCENE FISSURE-FILLINGS IN SOUTHEASTERN CHINA
SO NATURE
LA English
DT Article
ID adapis-parisiensis; early tertiary; affinity; discovery; dentition; africa; tarsiidae; pakistan; altanius; mongolia
AB We report the discovery of a fauna of primates from Eocene (approximately 45 Myr) deposits in China having a diversity greater than in European and North American localities of similar antiquity. From the many forms that will illuminate questions of primate phylogeny comes evidence for a basal radiation of primitive simians.
C1 ACAD SINICA, INST VERTEBRATE PALEONTOL & PALEOANTHROPOL, BEIJING 100044, PEOPLES R CHINA.
C3 Chinese Academy of Sciences; Institute of Vertebrate Paleontology & Paleoanthropology, CAS
RP BEARD, KC (corresponding author), CARNEGIE MUSEUM NAT HIST, VERTEBRATE PALEONTOL SECT, 4400 FORBES AVE, PITTSBURGH, PA 15213 USA.
NR 50
TC 157
Z9 180
U1 0
U2 17
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 604
EP 609
DI 10.1038/368604a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200051
PM 8145845
DA 2026-03-10
ER

PT J
AU MARTIN, JH
   COALE, KH
   JOHNSON, KS
   FITZWATER, SE
   GORDON, RM
   TANNER, SJ
   HUNTER, CN
   ELROD, VA
   NOWICKI, JL
   COLEY, TL
   BARBER, RT
   LINDLEY, S
   WATSON, AJ
   VANSCOY, K
   LAW, CS
   LIDDICOAT, MI
   LING, R
   STANTON, T
   STOCKEL, J
   COLLINS, C
   ANDERSON, A
   BIDIGARE, R
   ONDRUSEK, M
   LATASA, M
   MILLERO, FJ
   LEE, K
   YAO, W
   ZHANG, JZ
   FRIEDERICH, G
   SAKAMOTO, C
   CHAVEZ, F
   BUCK, K
   KOLBER, Z
   GREENE, R
   FALKOWSKI, P
   CHISHOLM, SW
   HOGE, F
   SWIFT, R
   YUNGEL, J
   TURNER, S
   NIGHTINGALE, P
   HATTON, A
   LISS, P
   TINDALE, NW
AF MARTIN, JH
   COALE, KH
   JOHNSON, KS
   FITZWATER, SE
   GORDON, RM
   TANNER, SJ
   HUNTER, CN
   ELROD, VA
   NOWICKI, JL
   COLEY, TL
   BARBER, RT
   LINDLEY, S
   WATSON, AJ
   VANSCOY, K
   LAW, CS
   LIDDICOAT, MI
   LING, R
   STANTON, T
   STOCKEL, J
   COLLINS, C
   ANDERSON, A
   BIDIGARE, R
   ONDRUSEK, M
   LATASA, M
   MILLERO, FJ
   LEE, K
   YAO, W
   ZHANG, JZ
   FRIEDERICH, G
   SAKAMOTO, C
   CHAVEZ, F
   BUCK, K
   KOLBER, Z
   GREENE, R
   FALKOWSKI, P
   CHISHOLM, SW
   HOGE, F
   SWIFT, R
   YUNGEL, J
   TURNER, S
   NIGHTINGALE, P
   HATTON, A
   LISS, P
   TINDALE, NW
TI TESTING THE IRON HYPOTHESIS IN ECOSYSTEMS OF THE EQUATORIAL PACIFIC-OCEAN
SO NATURE
LA English
DT Article
ID sub-arctic pacific; marine-phytoplankton; productivity; environments; limitation; seawater; growth; water; sea
AB The idea that iron might limit phytoplankton growth in large regions of the ocean has been tested by enriching an area of 64 km(2) in the open equatorial Pacific Ocean with iron. This resulted in a doubling of plant biomass, a threefold increase In chlorophyll and a fourfold increase in plant production. Similar increases were found in a chlorophyll-rich plume downstream of the Galapagos Islands, which was naturally enriched in iron. These findings indicate that iron limitation can control rates of phytoplankton productivity and biomass in the ocean.
C1 MOSS LANDING MARINE LABS,MOSS LANDING,CA 95039.
   DUKE UNIV,MARINE LAB,BEAUFORT,NC 28516.
   PLYMOUTH MARINE LAB,PLYMOUTH PL1 3DH,ENGLAND.
   USN,POSTGRAD SCH,MONTEREY,CA 93943.
   UNIV HAWAII,DEPT OCEANOG,HONOLULU,HI 96822.
   UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149.
   MONTEREY BAY AQUARIUM RES INST,PACIFIC GROVE,CA 93950.
   BROOKHAVEN NATL LAB,DIV OCEANOG & ATMOSPHER SCI,UPTON,NY 11973.
   MIT,DEPT CIVIL & ENVIRONM ENGN,RALPH M PARSONS LAB,CAMBRIDGE,MA 02139.
   NASA,GODDARD SPACE FLIGHT CTR,WALLOPS FLIGHT FACIL,WALLOPS ISL,VA 23337.
   UNIV E ANGLIA,SCH ENVIRONM SCI,NORWICH NR4 7TJ,NORFOLK,ENGLAND.
   TEXAS A&M UNIV,DEPT METEOROL,COLLEGE STN,TX 77843.
C3 Moss Landing Marine Laboratories; Duke University; Plymouth Marine Laboratory; United States Department of Defense; United States Navy; Naval Postgraduate School; University of Hawaii System; University of Miami; Monterey Bay Aquarium Research Institute; United States Department of Energy (DOE); Brookhaven National Laboratory; Massachusetts Institute of Technology (MIT); National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center; Wallops Flight Facility; University of East Anglia; Texas A&M University System; Texas A&M University College Station
NR 52
TC 1151
Z9 1324
U1 7
U2 378
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 123
EP 129
DI 10.1038/371123a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100054
DA 2026-03-10
ER

PT J
AU SCHLAEPFER, DD
   HANKS, SK
   HUNTER, T
   VANDERGEER, P
AF SCHLAEPFER, DD
   HANKS, SK
   HUNTER, T
   VANDERGEER, P
TI INTEGRIN-MEDIATED SIGNAL-TRANSDUCTION LINKED TO RAS PATHWAY BY GRB2 BINDING TO FOCAL ADHESION KINASE
SO NATURE
LA English
DT Article
ID protein-tyrosine kinase; cell-adhesion; sh3 domain; phosphorylation; receptor
AB THE cytoplasmic focal adhesion protein-tyrosine kinase (FAK) localizes with surface integrin receptors at sites where cells attach to the extracellular matrix. Increased FAK tyrosine phosphorylation occurs upon integrin engagement with fibronectin. Here we show that adhesion of murine NIH3T3 fibroblasts to fibronectin promotes SH2-domain-mediated association of the GRB2 adaptor protein and the c-Src protein-tyrosine kinase (PTK) with FAK in vivo, and also results in activation of mitogen-activated protein kinase (MAPK). In v-Src-transformed NIH3T3, the association of v-Src, GRB2 and Sos with FAK is independent of cell adhesion to fibronectin. The GRB2 SH2 domain binds directly to tyrosine-phosphorylated FAK. Mutation of tyrosine residue 925 of FAK (YENV motif) to phenylalanine blocks GRB2 SH2-domain binding to PAK in vitro. Our results show that fibronectin binding to integrins on NIH3T3 fibroblasts promotes c-Src and FAK association and formation of an integrin-activated signalling complex. Phosphorylation of FAK at Tyr 925 upon fibronectin stimulation creates an SH2-binding site for GRB2 which may link integrin engagement to the activation of the Ras/MAPK signal transduction pathway.
C1 VANDERBILT UNIV, SCH MED, DEPT CELL BIOL, NASHVILLE, TN 37232 USA.
C3 Vanderbilt University
RP SCHLAEPFER, DD (corresponding author), SALK INST, MOLEC BIOL & VIROL LAB, POB 85800, SAN DIEGO, CA 92186 USA.
NR 22
TC 1488
Z9 1680
U1 0
U2 70
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 786
EP 791
DI 
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200055
PM 7997267
DA 2026-03-10
ER

PT J
AU HIROI, Z
   KOBAYASHI, N
   TAKANO, M
AF HIROI, Z
   KOBAYASHI, N
   TAKANO, M
TI PROBABLE HOLE-DOPED SUPERCONDUCTIVITY WITHOUT APICAL OXYGENS IN (CA, NA)(2)CUO2CL2
SO NATURE
LA English
DT Article
ID tc
AB THE presence of apical oxygens (above or below the CuO2 planes) has been regarded as indispensable for the occurrence of hole-doped superconductivity in the high-transition-temperature (high-T-c) copper oxide superconductors(1,2). We have opposed this view(3,4), on the basis of studies in compounds such as (Ca, Sr)(1)-xCuO2-(y) and Srn+1CunO2n+1+1+delta; however, our conclusions have been questioned in subsequent Work(5,6). Here we provide strong evidence for hole-doped superconductivity in the absence of apical oxygens, by showing that Ca2CuO2Cl2 can be rendered superconducting by doping with sodium. The compound contains CuO2 planes as in La2CuO4, but all of the oxygen atoms at the apices of tbe CuO6 octahedra found in La2CuO4 are replaced by chlorine, and the lanthanum atoms by calcium(7). The apparent difference in mass and electronic character between chlorine and oxygen might strongly affect the electronic structure of the CuO2 planes if the contributions of the apical atoms were significant. But we find hole-doped superconductivity in (Ca, Na)(2)CuO2Cl2 at rather high transition temperatures (26K at maximum), which are only slightly less than those of doped La2CuO4 (ref. 8). This implies that the apical atoms do not play a significant role in the electron pairing mechanism leading to high-T-c superconductivity.
RP HIROI, Z (corresponding author), KYOTO UNIV,INST CHEM RES,UJI,KYOTO 611,JAPAN.
NR 15
TC 152
Z9 163
U1 2
U2 36
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 139
EP 141
DI 10.1038/371139a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100057
DA 2026-03-10
ER

PT J
AU HUBBARD, SR
   WEI, L
   ELIS, L
   HENDRICKSON, WA
AF HUBBARD, SR
   WEI, L
   ELIS, L
   HENDRICKSON, WA
TI CRYSTAL-STRUCTURE OF THE TYROSINE KINASE DOMAIN OF THE HUMAN INSULIN-RECEPTOR
SO NATURE
LA English
DT Article
ID dependent protein-kinase; catalytic subunit; autophosphorylation; phosphotransferase; phosphorylation; identification; inhibitor; features; family; cells
AB The X-ray crystal structure of the tyrosine kinase domain of the human insulin receptor has been determined by multiwavelength anomalous diffraction phasing and refined to 2.1 Angstrom resolution. The structure reveals the determinants of substrate preference for tyrosine rather than serine or threonine and a novel autoinhibition mechanism whereby one of the tyrosines that is autophosphorylated in response to insulin, Tyr 1,162, is bound in the active site.
C1 COLUMBIA UNIV,HOWARD HUGHES MED INST,NEW YORK,NY 10032.
   TEXAS A&M UNIV,INST BIOSCI & TECHNOL,WM KECK CTR GENOME INFORMAT,HOUSTON,TX 77030.
C3 Columbia University; Howard Hughes Medical Institute; Texas A&M University System
RP HUBBARD, SR (corresponding author), COLUMBIA UNIV,DEPT BIOCHEM & MOLEC BIOPHYS,NEW YORK,NY 10032, USA.
NR 47
TC 971
Z9 1157
U1 0
U2 50
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 746
EP 754
DI 10.1038/372746a0
PG 9
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200043
PM 7997262
DA 2026-03-10
ER

PT J
AU WOO, DDL
   MIAO, SYP
   PELAYO, JC
   WOOLF, AS
AF WOO, DDL
   MIAO, SYP
   PELAYO, JC
   WOOLF, AS
TI TAXOL INHIBITS PROGRESSION OF CONGENITAL POLYCYSTIC KIDNEY-DISEASE
SO NATURE
LA English
DT Article
ID protooncogene expression; cyst formation; cyclic-amp; microtubules; cells; secretion; membrane; growth; mouse; epithelia
AB POLYCYSTIC kidney diseases (PKD) are the most common hereditary diseases of the human kidney and account for ten per cent of patients requiring renal transplantation or dialysis. Renal cyst formation has been attributed to enhanced cell proliferation, unbalanced cell death, abnormal targeting of membrane proteins; aberrant kidney development and tubular obstruction, but there is no treatment that blocks the formation and enlargement of renal cysts. We have now developed an in vitro model of spontaneous cyst formation that distinguishes polycystic kidney epithelium from its normal counterpart. Inhibitors of DNA, RNA and protein synthesis did not prevent in vitro cyst formation, but this was reversibly inhibited by ouabain, amiloride and the microtubule-specific agents colchicine, vinblastine and taxol. The cpk mouse is a well-characterized recessive PKD model(1-3) and we find that cpk/cpk mice develop PKD and die from uraemia by 4-5 weeks of age, but when treated weekly with taxol they survive for more than 200 days with minimal loss of renal function, show limited collecting-dust cyst enlargement, and attain adult size. Our results indicate that the microtubule cytoskeleton has a central role in the pathogenesis of PKD in cpk mice and that taxol may also be useful in treating human PKD.
C1 UNIV CALIF LOS ANGELES,SCH MED,DEPT PAEDIAT,LOS ANGELES,CA 90024.
   INST CHILD HLTH,DEV BIOL UNIT,LONDON WC1N 1EH,ENGLAND.
C3 University of California System; University of California Los Angeles; University of California Los Angeles Medical Center; David Geffen School of Medicine at UCLA; University of London; University College London
RP WOO, DDL (corresponding author), UNIV CALIF LOS ANGELES,SCH MED,DEPT MED,7-155 FACTOR BLDG,LOS ANGELES,CA 90024, USA.
NR 26
TC 133
Z9 186
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 750
EP 753
DI 10.1038/368750a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300061
PM 7908721
DA 2026-03-10
ER

PT J
AU ZHANG, SW
   SRINIVASAN, MV
AF ZHANG, SW
   SRINIVASAN, MV
TI PRIOR EXPERIENCE ENHANCES PATTERN-DISCRIMINATION IN INSECT VISION
SO NATURE
LA English
DT Article
AB IT is well known that prior knowledge or experience aids us tremendously in uncovering objects that are poorly visible, partially hidden or camouflaged(1-3). Is such enhancement in performance unique to higher animals? Here we find that bees cannot be trained directly to distinguish between differently shaped, camouflaged figures. They can, however, learn to break the camouflage and make the discrimination if they are trained initially on a simpler task that exposes them to shapes that are presented later in camouflage. Evidently, even organisms with relatively simple nervous systems can use prior experience to advantage in processing visual images.
RP ZHANG, SW (corresponding author), AUSTRALIAN NATL UNIV,RES SCH BIOL SCI,CTR VISUAL SCI,POB 475,CANBERRA,ACT 2601,AUSTRALIA.
NR 10
TC 73
Z9 75
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 330
EP 332
DI 10.1038/368330a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500044
DA 2026-03-10
ER

PT J
AU MUTA, T
   KUROSAKI, T
   MISULOVIN, Z
   SANCHEZ, M
   NUSSENZWEIG, MC
   RAVETCH, JV
AF MUTA, T
   KUROSAKI, T
   MISULOVIN, Z
   SANCHEZ, M
   NUSSENZWEIG, MC
   RAVETCH, JV
TI A 13-AMINO-ACID MOTIF IN THE CYTOPLASMIC DOMAIN OF FC-GAMMA-RIIB MODULATES B-CELL RECEPTOR SIGNALING
SO NATURE
LA English
DT Article
ID lymphocytes-b; tyrosine phosphorylation; antigen receptors; zeta-chain; activation; heterogeneity; immunoglobulin; complex; tail; beta
AB THE FC receptor on B lymphocytes, Fc gamma RIIB (beta 1 isoform), helps to modulate B-cell activation triggered by the surface immuno-globulin complex(1,2). Crosslinking of membrane immunoglobulin by antigen or anti-IG F(ab')(2) antibody induces a transient increase in cytosolic free Ca2+, a rise in inositol-3-phosphate, activation of protein kinase C, and enhanced protein tyrosine phosphorylation(3-5). Crosslinking Fc gamma RIIB with the surface immunoglobulin complex confers a dominant signal that prevents or aborts lymphocyte activation triggered through the ARH-1 motifs of the signal transduction subunits Ig-alpha and Ig-beta. Here we show that Fc gamma RIIB modulates membrane immunoglobulin-induced Ca2+ mobilization by; inhibiting Ca2+ influx, without changing the pattern of tyrosine phosphorylation. A 13-amino-acid motif in the cytoplasmic domain of Fc gamma RIIB is both necessary and sufficient for this effect. Tyrosine at residue 309 in this motif is phosphorylated upon co-crosslinking with surface immunoglobulin; mutation of this residue aborts the inhibitory effect of Fc gamma RIIB. This inhibition is directly coupled to signalling mediated through Ig-alpha and Ig-beta as evidenced by chimaeric IgM/alpha and IgM/beta molecules. The 13-residue motif in Fc gamma RIIB controls lymphocyte activation by inhibiting a Ca2+ signalling pathway triggered through ARH-1 motifs as a result of recruitment of novel SH2-containing proteins that interact with this Fc gamma RIIB cytoplasmic motif.
C1 ROCKEFELLER UNIV, NEW YORK, NY 10021 USA.
C3 Rockefeller University
RP MUTA, T (corresponding author), SLOAN KETTERING INST, DEWITT WALLACE RES LAB, 1275 YORK AVE, NEW YORK, NY 10021 USA.
NR 26
TC 442
Z9 517
U1 0
U2 7
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 70
EP 73
DI 10.1038/368070a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900056
PM 8107887
DA 2026-03-10
ER

PT J
AU MOMBURG, F
   ROELSE, J
   HOWARD, JC
   BUTCHER, GW
   HAMMERLING, GJ
   NEEFJES, JJ
AF MOMBURG, F
   ROELSE, J
   HOWARD, JC
   BUTCHER, GW
   HAMMERLING, GJ
   NEEFJES, JJ
TI SELECTIVITY OF MHC-ENCODED PEPTIDE TRANSPORTERS FROM HUMAN, MOUSE AND RAT
SO NATURE
LA English
DT Article
ID major histocompatibility complex; class-i molecules; antigen presentation; linked transporter; rma-s; expression; invitro; hla-b27; cells; genes
AB MAJOR histocompatibility complex (MHC) class I molecules present peptides from degraded intracellular antigens to CD8(+) T cells(1). These peptides are translocated in an ATP-dependent fashion(2-4) into the lumen of the endoplasmic reticulum (ER) for binding to class I molecules(5,6) by means of the MHC-encoded transporters associated with antigen processing, TAP1 and TAP2. These are members of a family of proteins containing an ATP-binding cassette and form heterodimers in the ER membrane(7-10). Defects in the genes encoding TAP1 or TAP2 account for impaired class I assembly and antigen presentation in several human and rodent cell lines(7,11-13). Whereas MHC class I molecules select peptides according to binding motifs(14-17), it is not clear to what extent the TAP1-TAP2 transporters have peptide sequence and length specificity. Previous studies of the rat MHC class I molecule, RT1A(a), suggested a specific conveyance of peptides by rat TAP1-TAP2 (ref. 18). Here we substitute the amino- and carboxy-terminal and the penultimate amino-acid residues of model peptides to show that these residues influence the efficiency of transport. Human TAP and rat TAP(a) translocated peptides with hydrophobic and basic C termini, whereas mouse TAP and rat TAP(u) preferred peptides with hydrophobic C termini. This pattern correlates with the predominant peptide binding profiles of mouse and human class I molecules.
C1 NETHERLANDS CANC INST,DIV CELLULAR BIOCHEM,1066 CX AMSTERDAM,NETHERLANDS.
   BABRAHAM INST,AGR & FOOD RES COUNCIL,DEPT IMMUNOL,CAMBRIDGE CB2 4AT,ENGLAND.
C3 Netherlands Cancer Institute; UK Research & Innovation (UKRI); Biotechnology and Biological Sciences Research Council (BBSRC); Babraham Institute
RP MOMBURG, F (corresponding author), GERMAN CANC RES CTR,TUMOR IMMUNOL PROGRAM,NEUENHEIMER FELD 280,D-69120 HEIDELBERG,GERMANY.
NR 28
TC 340
Z9 368
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 648
EP 651
DI 10.1038/367648a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800055
PM 8107849
DA 2026-03-10
ER

PT J
AU MORENO, S
   NURSE, P
AF MORENO, S
   NURSE, P
TI REGULATION OF PROGRESSION THROUGH THE G1 PHASE OF THE CELL-CYCLE BY THE RUM1(+) GENE
SO NATURE
LA English
DT Article
ID yeast schizosaccharomyces-pombe; fission yeast; dna-replication; saccharomyces-cerevisiae; protein-kinase; s-phase; mitosis; division; sequence; p34cdc2
AB The rum1+ gene is identified as a new regulator of G1 progression in fission yeast. It influences three aspects of G1 regulation: determination of the length of G1, dependence of S phase upon completion of mitosis, and restraint of mitosis until G1 is finished. We propose that it has a central role in regulating the G1 phase of the cell cycle.
C1 ICRF, LONDON WCZA 3PX, ENGLAND.
   UNIV OXFORD, DEPT BIOCHEM, ICRF, CELL CYCLE GRP, OXFORD OX1 1QU, ENGLAND.
C3 University of Oxford
NR 44
TC 316
Z9 340
U1 0
U2 11
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 236
EP 242
DI 10.1038/367236a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400045
PM 8121488
DA 2026-03-10
ER

PT J
AU ELLINOR, PT
   ZHANG, JF
   HORNE, WA
   TSIEN, RW
AF ELLINOR, PT
   ZHANG, JF
   HORNE, WA
   TSIEN, RW
TI STRUCTURAL DETERMINANTS OF THE BLOCKADE OF N-TYPE CALCIUM CHANNELS BY A PEPTIDE NEUROTOXIN
SO NATURE
LA English
DT Article
ID omega-conotoxin gvia; ca2+ channels; functional expression; peripheral neurons; brain; subunit; sensitivity; selectivity; synapses
AB NEUROTOXINS that selectively block Na+, K+ or Ca2+ channels have provided valuable information about the functional diversity of the voltage-gated channel superfamily(1). For Ca2+ channels, a variety of toxins have been found to block individual channel types(2,3). The best-known example is omega-conotoxin-GVIA, a member of a large family of peptide toxins derived from venomous cone snails(2,3), which potently and selectively blocks N-type Ca2+ channels(4-9), allowing their purification(10,11), cellular localization(12,13), and the elucidation of their roles in Ca2+ entry(14), neurotransmitter release(15,16) and neuronal migration(17). In contrast to Na+ and K+ channels, little is known about the molecular features that underlie Ca2+-channel susceptibility to toxin block; it is also unknown whether block occurs by direct physical occlusion(3) or an action on channel gating(18). Here we describe structural determinants of the N-type Ca2+ channel's interaction with omega-conotoxin-GVIA. When chimaeras combining individual motifs from the N-type channel and from a channel insensitive to omega-conotoxin-GVIA were expressed in Xenopus oocytes, each of the four motifs appeared to contribute to interaction with the toxin. The most dramatic effects on toxin interactions were seen at a single cluster of residues in the large putative extracellular loop between IIIS5 and IIIH5, consistent with a direct pore-blocking mechanism. These results provide a starting point for delineating the architecture of the outer vestibule of the Ca2+ channel.
C1 STANFORD UNIV,MED CTR,DEPT CELLULAR & MOLEC PHYSIOL,STANFORD,CA 94305.
   NEUREX CORP,MENLO PK,CA 94025.
C3 Stanford University
NR 29
TC 171
Z9 189
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 272
EP 275
DI 10.1038/372272a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900053
PM 7969473
DA 2026-03-10
ER

PT J
AU EMLEN, ST
   WREGE, PH
AF EMLEN, ST
   WREGE, PH
TI GENDER, STATUS AND FAMILY FORTUNES IN THE WHITE-FRONTED BEE-EATER
SO NATURE
LA English
DT Article
ID territory quality; helping-behavior; genetic-analysis; evolution; kinship; dispersal; honeybee; kenya; wrens
AB Models of how people make decisions are central to economic theory. But when cast in a darwinian framework, such models provide insights into animal social behaviour. This is especially true of family-based societies in which the profitability of pursuing different behaviours is strongly influenced by gender, kinship and social position within the group. The potential of this approach is shown by modelling the reproductive decisions facing individuals in a complex bird society, that of the white-fronted bee-eater.
RP EMLEN, ST (corresponding author), CORNELL UNIV, NEUROBIOL & BEHAV SECT, ITHACA, NY 14853 USA.
NR 47
TC 26
Z9 29
U1 0
U2 25
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 129
EP 132
DI 10.1038/367129a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000048
DA 2026-03-10
ER

PT J
AU RYGIEWICZ, PT
   ANDERSEN, CP
AF RYGIEWICZ, PT
   ANDERSEN, CP
TI MYCORRHIZAE ALTER QUALITY AND QUANTITY OF CARBON ALLOCATED BELOW GROUND
SO NATURE
LA English
DT Article
ID soil; seedlings; hyphae; roots; flow; co2
AB PLANTS and sails are a critically important element in the global carbon-energy equation. It is estimated that in forest ecosystems over two-thirds of the carbon is contained in soils and peat deposits(1). Despite the importance of forest soils in the global carbon cycle, fluxes of carbon associated with fundamental processes and soil functional groups are inadequately quantified, limiting our understanding of carbon movement and sequestration in soils. We report here the direct measurement of carbon id and through all major pools of a mycorrhizal (fungus-root) coniferous seedling (a complete carbon budget). The mycorrhizal symbiont reduces overall retention of carbon in the plant-fungus symbiosis by increasing carbon in roots and below-ground respiration and reducing its retention and release above ground. Below ground, mycorrhizal plants shifted allocation of carbon to pools that are rapidly turned over, primarily to fine roots and fungal hyphae, and host root and fungal respiration. Mycorrhizae alter the size of below-ground carbon pools, the quality and, therefore, the retention time of carbon below ground. Our data indicate that if elevated atmospheric CO2 and altered climate stressors alter mycorrhizal colonization in forests, the role of forests in sequestering carbon could be altered.
RP RYGIEWICZ, PT (corresponding author), US EPA,ENVIRONM RES LAB,200 SW 35TH ST,CORVALLIS,OR 97333, USA.
NR 21
TC 206
Z9 230
U1 0
U2 114
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 58
EP 60
DI 10.1038/369058a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000052
DA 2026-03-10
ER

PT J
AU ELSER, JJ
   HASSETT, RP
AF ELSER, JJ
   HASSETT, RP
TI A STOICHIOMETRIC ANALYSIS OF THE ZOOPLANKTON-PHYTOPLANKTON INTERACTION IN MARINE AND FRESH-WATER ECOSYSTEMS
SO NATURE
LA English
DT Article
ID planktonic cladocerans; p-limitation; phosphorus; nitrogen; ratio; growth; carbon; nutrition
AB IN the 35 years since A. C. Redfield's classic paper(1), the use of elemental ratios has become widespread in marine and freshwater phytoplankton studies(2,3). But nutrient ratios have only recently been studied elsewhere in pelagic ecosystems, such as the producer-consumer interface(4,5). Here we report the results of the first study, to our knowledge, of N:P ratios in pelagic producers and consumers (phytoplankton and zooplankton) in lacustrine and marine habitats. The N:P ratio of phytoplankton was higher in lakes than in marine sites; however, N:P ratios were higher in marine zooplankton than in freshwater zooplankton. The elemental imbalance of the phytoplankton-zooplankton interaction (N:P-food-N:P-consumers) in lakes was positive and exceeded the negative imbalance in marine sites; thus P-deficient food may limit zooplankton growth in lakes but not in oceans. Stoichiometric calculations(6) indicated that consumer-driven nutrient recycling ratios in lakes may be 4-6 times higher than in marine systems. Consistent with this difference, phytoplankton P-limitation was more prevalent in lakes than in marine sites. Thus, the ecological stoichiometry of the zooplankton-phytoplankton interaction differs qualitatively in freshwater and marine ecosystems.
RP ELSER, JJ (corresponding author), ARIZONA STATE UNIV,DEPT ZOOL,TEMPE,AZ 85287, USA.
NR 22
TC 232
Z9 261
U1 3
U2 149
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 211
EP 213
DI 10.1038/370211a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100050
DA 2026-03-10
ER

PT J
AU STERN, LJ
   BROWN, JH
   JARDETZKY, TS
   GORGA, JC
   URBAN, RG
   STROMINGER, JL
   WILEY, DC
AF STERN, LJ
   BROWN, JH
   JARDETZKY, TS
   GORGA, JC
   URBAN, RG
   STROMINGER, JL
   WILEY, DC
TI CRYSTAL-STRUCTURE OF THE HUMAN CLASS-II MHC PROTEIN HLA-DR1 COMPLEXED WITH AN INFLUENZA-VIRUS PEPTIDE
SO NATURE
LA English
DT Article
ID binding; molecules; motifs; identification; recognition; epitopes; antigen; hla-b27; models
AB An influenza virus peptide binds to HLA-DR1 in an extended conformation with a pronounced twist. Thirty-five per cent of the peptide surface is accessible to solvent and potentially available for interaction with the antigen receptor on T cells. pockets in the peptide-binding site accommodate five of the thirteen side chains of the bound peptide, and explain the peptide specificity of HLA-DR1. Twelve hydrogen bonds between conserved HLA-DR1 residues and the main chain of the peptide provide a universal mode of peptide binding, distinct from the strategy used by class I histocompatibility proteins.
C1 HARVARD UNIV,HOWARD HUGHES MED INST,CAMBRIDGE,MA 02138.
   HARVARD UNIV,DEPT BIOCHEM & MOLEC BIOL,CAMBRIDGE,MA 02138.
   BRANDEIS UNIV,ROSENSTIEL RES CTR,WALTHAM,MA 02254.
   CHILDRENS HOSP PITTSBURGH,RANGOS RES CTR,PITTSBURGH,PA 15213.
   UNIV PITTSBURGH,MED CTR,PITTSBURGH,PA 15213.
C3 Harvard University; Howard Hughes Medical Institute; Harvard University; Brandeis University; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh
NR 51
TC 1473
Z9 1609
U1 0
U2 142
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 215
EP 221
DI 10.1038/368215a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000046
PM 8145819
DA 2026-03-10
ER

PT J
AU GOULDING, EH
   TIBBS, GR
   SIEGELBAUM, SA
AF GOULDING, EH
   TIBBS, GR
   SIEGELBAUM, SA
TI MOLECULAR MECHANISM OF CYCLIC-NUCLEOTIDE-GATED CHANNEL ACTIVATION
SO NATURE
LA English
DT Article
ID dependent protein-kinase; subunit stoichiometry; binding-specificity; potassium channels; receptor chimeras; inactivation; membrane; domain; gmp
AB STUDIES on the activation of ligand- and voltage-gated ion channels have identified regions involved in both ligand binding(1) and voltage sensing(2), but relatively little is known about how such domains are coupled to channel opening. Here we investigate the structural basis for the activation of cyclic-nucleotide-gated channels, which are directly opened by cytoplasmic cyclic nucleotides(3,4) but are structurally homologous to voltage-gated channels(5-7). By constructing chimaeras between cyclic-nucleotide-gated channels cloned from bovine retinal photoreceptors(8) and catfish olfactory neurons(7), we identify two distinct domains that are important for ligand binding and channel gating. A putative alpha-helix in the carboxy-terminal binding domain determines the selectivity of the channel for activation by cGMP relative to cAMP. A domain in the amino-terminal region determines the ease with which channels open and thus influences agonist efficacy. We propose that channel opening is coupled to an allosteric conformational change in the binding site which enhances agonist binding. Thus, cyclic nucleotides activate the channel by binding tightly to the open state and stabilizing it.
C1 COLUMBIA UNIV,HOWARD HUGHES MED INST,DEPT PHARMACOL,NEW YORK,NY 10032.
C3 Howard Hughes Medical Institute; Columbia University
RP GOULDING, EH (corresponding author), COLUMBIA UNIV,HOWARD HUGHES MED INST,CTR NEUROBIOL & BEHAV,DEPT PHYSIOL,722 W 168TH ST,NEW YORK,NY 10032, USA.
NR 30
TC 182
Z9 188
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 369
EP 374
DI 10.1038/372369a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700058
PM 7969497
DA 2026-03-10
ER

PT J
AU JAMES, AF
   XIE, LH
   FUJITANI, Y
   HAYASHI, S
   HORIE, M
AF JAMES, AF
   XIE, LH
   FUJITANI, Y
   HAYASHI, S
   HORIE, M
TI INHIBITION OF THE CARDIAC PROTEIN-KINASE A-DEPENDENT CHLORIDE CONDUCTANCE BY ENDOTHELIN-1
SO NATURE
LA English
DT Article
ID guinea-pig atria; autonomic regulation; myocytes; cells; contraction; activation; mechanism; receptor; subunits; isozyme
AB ENDOTHELIN-1 is a peptide hormone constitutively secreted by vascular and endocardial endothelial cells(1-3). Secretion of endothelin-1 is increased under certain pathophysiological conditions, including coronary vasospasm, cardiac ischaemia and myocardial infarction. We have examined the effect of endothelin-1 on the protein kinase A (PKA)-dependent chloride current in voltage-clamped guinea pig ventricular myocytes. This conductance, induced by catecholamines through beta-adrenergic receptors, counteracts the simultaneously increased L-type calcium current by shortening the action potential duration(4-6). We report here that endothelin-1, acting through ET(A) (endothelin-1-selective) receptors, inhibited the current through a pertussis toxin-sensitive mechanism, analogous to muscarinic receptors, by reducing the intracellular cyclic AMP concentration. This effect of endothelin-1 should help protect the ventricle against potentially arrhythmogenic shortening of the action potential during ischaemia when the circulating levels of catecholamines are increased.
C1 KYOTO UNIV,FAC MED,DEPT INTERNAL MED 3,KYOTO 606,JAPAN.
   CIBA GEIGY JAPAN LTD,INT RES LABS,TAKARAZUKA,HYOGO 665,JAPAN.
   NATL INST PHYSIOL SCI,DEPT CELLULAR & MOLEC PHYSIOL,OKAZAKI,AICHI 444,JAPAN.
C3 Kyoto University; National Institutes of Natural Sciences (NINS) - Japan; National Institute for Physiological Sciences (NIPS)
NR 26
TC 83
Z9 85
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 297
EP 300
DI 10.1038/370297a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900065
PM 8035878
DA 2026-03-10
ER

PT J
AU CAYRE, M
   STRAMBI, C
   STRAMBI, A
AF CAYRE, M
   STRAMBI, C
   STRAMBI, A
TI NEUROGENESIS IN AN ADULT INSECT BRAIN AND ITS HORMONAL-CONTROL
SO NATURE
LA English
DT Article
ID drosophila-melanogaster; nervous-system; acheta-domesticus; juvenile; increase; patterns; bee; rat
AB HORMONALLY mediated changes in behaviour patterns are found in many animal species, including adult insects(1-4), raising the possibility that the neurological modifications linked with such changes could be mediated by morphogenetic hormones. Neuronal plasticity and neurogenesis in the adult brain have rarely been reported in vertebrates(5-10), and in adult insects only modifications of mushroom body volumes or fibres have been described(11-14). Here we report the presence of undifferentiated cells, located dorsally in mushroom bodies of the house cricket Acheta domesticus, that persist, divide and give rise to cortical interneurons during adult life. Furthermore, juvenile hormone, which induces oviposition behaviour in adult crickets(2,3), acts on neurogenesis in this cell cluster. Females deprived of juvenile hormone showed a significant decrease in cell division, which was reversed by hormone injection. Production of juvenile hormone therefore appears to be a major factor in the adaptation of the brain to concomitant physiological and behavioural changes in adult insects.
RP CAYRE, M (corresponding author), CNRS, NEUROBIOL LAB, 31 CHEMIN JOSEPH AIGUIER, F-13402 MARSEILLE 20, FRANCE.
NR 33
TC 142
Z9 152
U1 1
U2 14
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 57
EP 59
DI 10.1038/368057a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900051
DA 2026-03-10
ER

PT J
AU IMBALZANO, AN
   KWON, H
   GREEN, MR
   KINGSTON, RE
AF IMBALZANO, AN
   KWON, H
   GREEN, MR
   KINGSTON, RE
TI FACILITATED BINDING OF TATA-BINDING PROTEIN TO NUCLEOSOMAL DNA
SO NATURE
LA English
DT Article
ID rna polymerase-ii; transcription factor; chromatin structure; crystal-structure; minor-groove; tfiid binds; box complex; major late; yeast; invitro
AB BINDING of the TATA-binding protein (TBP) to the TATA box is required for transcription from many eukaryotic promoters in gene expression. Regulation of this binding is therefore likely to be an important determinant of promoter activity. Incorporation of the TATA sequence into nucleosomes dramatically reduces transcription initiation(1-3), presumably because of stereochemical constraints on binding of general transcription factors. Biochemical and genetic studies imply that cellular factors such as yeast SWI/SNF are required for activator function and might alter chromatin structure(4-11). One step that could be regulated during the activation process is TBP binding in chromatin(12,13) We show here that binding of TBP to the TATA sequence is severely inhibited by incorporation of this sequence into a nucleosome. Inhibition can be overcome by ATP-dependent alterations in nucleosomal DNA structure mediated by hSWI/SNF, a putative human homologue of the yeast SWI/SNF complex. Additionally, the orientation of the TATA sequence relative to the surface of the histone core affects the access of TBP. We propose that the dynamic remodelling of chromatin structure to allow TBP binding is a key step in the regulation of eukaryotic gene expression.
C1 MASSACHUSETTS GEN HOSP,DEPT MOLEC BIOL,BOSTON,MA 02114.
   HARVARD UNIV,SCH MED,DEPT GENET,BOSTON,MA 02115.
   UNIV MASSACHUSETTS,MED CTR,HOWARD HUGHES MED INST,PROGRAM MOLEC MED,WORCESTER,MA 01605.
C3 Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Harvard University; Harvard Medical School; Howard Hughes Medical Institute; University of Massachusetts System; University of Massachusetts Worcester
NR 30
TC 538
Z9 614
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 481
EP 485
DI 10.1038/370481a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700062
PM 8047170
DA 2026-03-10
ER

PT J
AU UNWIN, DM
   BAKHURINA, NN
AF UNWIN, DM
   BAKHURINA, NN
TI SORDES PILOSUS AND THE NATURE OF THE PTEROSAUR FLIGHT APPARATUS
SO NATURE
LA English
DT Article
AB IT is now generally accepted that pterosaurs, Mesozoic reptiles, were true fliers, but the nature of their flight apparatus is still much disputed. Evidence has been presented in favour of bird-like reconstructions with narrow, stiff wings free of the legs(1-6) and bat-like reconstructions with extensive wings incorporating both fore and hind limbs(7-10), but the Solnhofen Limestone pterosaurs, upon which these models are based, are not sufficiently well preserved to resolve these conflicting interpretations. Here we present a new model, founded on Sordes pilosus from the Jurassic of middle Asia (ref. 11, and N.N.B. and D.M.U., manuscript submitted), in which exceptionally well preserved wing membranes show that the hind limbs of pterosaurs were intimately involved in the flight apparatus; connected externally to the main wing membrane and internally by a uropatagium, controlled by the fifth toe. Sordes also reveals that, uniquely among flying vertebrates, pterosaurs had a structurally non-homogenous flight surface with a stiffened outer half and a softer, more extensible inner region.
C1 RUSSIAN ACAD SCI, INST PALAEONTOL, MOSCOW 117647, RUSSIA.
C3 Russian Academy of Sciences
RP UNWIN, DM (corresponding author), UNIV BRISTOL, DEPT GEOL, QUEENS RD, BRISTOL BS8 1RJ, ENGLAND.
NR 28
TC 90
Z9 98
U1 0
U2 22
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 62
EP 64
DI 10.1038/371062a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100050
DA 2026-03-10
ER

PT J
AU HARLAN, JE
   HAJDUK, PJ
   YOON, HS
   FESIK, SW
AF HARLAN, JE
   HAJDUK, PJ
   YOON, HS
   FESIK, SW
TI PLECKSTRIN HOMOLOGY DOMAINS BIND TO PHOSPHATIDYLINOSITOL-4,5-BISPHOSPHATE
SO NATURE
LA English
DT Article
ID adrenergic-receptor kinase; phospholipase c-delta-1; signaling proteins; ph domain; expression
AB THE pleckstrin homology (PH) domain is a new protein module of around 100 amino acids found in several proteins involved in signal transduction(1-5). Although its specific function has yet to be elucidated, the carboxy-terminal regions of many PH domains bind to the beta gamma subunits of G proteins(6,7). On the basis of structural similarities between PH domains and Lipid-binding proteins, we have proposed that PH domains may be binding to lipophilic molecules(8). indeed, many of the proteins that contain this domain associate with phospholipid membrane(6,9,10), and disruption of this domain can interfere with membrane association(6,11). Here we report that PH domains bind to phosphatidylinositol-4,5-bisphosphate and show that the lipid-binding site is located at the Lip of the beta-barrel. This suggests that PH domains may be important for membrane localization of proteins through interactions with phosphatidylinositol-4,5-bisphosphate.
C1 ABBOTT LABS,DIV PHARMACEUT DISCOVERY,NMR RES,ABBOTT PK,IL 60064.
C3 Abbott Laboratories
NR 19
TC 701
Z9 795
U1 1
U2 21
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 168
EP 170
DI 10.1038/371168a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100067
PM 8072546
DA 2026-03-10
ER

PT J
AU NELSON, BH
   LORD, JD
   GREENBERG, PD
AF NELSON, BH
   LORD, JD
   GREENBERG, PD
TI CYTOPLASMIC DOMAINS OF THE INTERLEUKIN-2 RECEPTOR BETA-CHAIN AND GAMMA-CHAIN MEDIATE THE SIGNAL FOR T-CELL PROLIFERATION
SO NATURE
LA English
DT Article
ID il-2 receptor; tyrosine kinase; functional component; gm-csf; transduction; activation; binding; phosphorylation; involvement; expression
AB The interleukin-2 (IL-2R) consists of three distinct chains (alpha, beta, gamma) which bind IL-2 and generate a proliferative signal in T cells(1). To define the mechanism of receptor activation, chimaeric receptors were constructed from the intracellular region of either IL-2R beta or IL-2R gamma and the extracellular region of c-kit, a receptor tyrosine kinase that homodimerizes on binding stem cell factor (SCF)(2). We report here that binding of SCF to the beta-chain chimaera induced proliferation of the pro-B-cell line BA/F3, but not T cells. But in T cells expressing both the beta- and gamma-chain chimaeras, SCF induced proliferation and tyrosine phosphorylation characteristic of the native IL-2R signal. Chimaeric IL-2 receptor beta and gamma chains constructed with the heterodimeric extracellular regions of the granulocyte-macrophage colony stimulating factor receptor (GM-CSFR) also provided the IL-2R signal. Thus, heterodimerization of the cytoplasmic domains of n-2R beta and -gamma appears necessary and sufficient for signalling in T cells.
C1 UNIV WASHINGTON,DEPT IMMUNOL,SEATTLE,WA 98195.
   UNIV WASHINGTON,DEPT MED,SEATTLE,WA 98195.
C3 University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle
RP NELSON, BH (corresponding author), FRED HUTCHINSON CANC RES CTR,1124 COLUMBIA ST M758,SEATTLE,WA 98104, USA.
NR 30
TC 307
Z9 337
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 333
EP 336
DI 10.1038/369333a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900054
PM 7514277
DA 2026-03-10
ER

PT J
AU CLACK, JA
AF CLACK, JA
TI EARLIEST KNOWN TETRAPOD BRAINCASE AND THE EVOLUTION OF THE STAPES AND FENESTRA OVALIS
SO NATURE
LA English
DT Article
AB ACANTHOSTEGA gunnari, from the Upper Devonian (Famennian) of East Greenland, is the mast primitive known tetrapod, and retains many fish-like characters I report here the discovery of further well preserved specimens that show the earliest known tetrapod braincase, and shed light on the history of the tetrapod ear region. The fenestra ovalis is shown to be derived directly from the vestibular fontanelle(5,6), a hole in the sidewall of the braincase of fishes seen in their embryology and in primitive fossil fish adults. The hole is not a uniquely tetrapod character(7,8). A specialized auditory fenestra ovalis may have evolved more than once among tetrapods. As in other tetrapods, the stapedial footplate of Acanthostega fitted into the fenestra ovalis, but instead of being free to vibrate as part of an ear, was firmly held there, forming a major component of the braincase wall. It was the only component linking the otic capsule to the palate. Though the stapes may have carried muscles operating a spiracular valve, the new material suggests that it was not a mobile component of the skull as previously suggested(4). The stapes, spatially replacing parts of the fish braincase including the process carrying facets for the hyomandibular articulation(9), has a footplate which incorporates both heads of the sarcopterygian hyomandibula.
RP CLACK, JA (corresponding author), UNIV CAMBRIDGE,ZOOL MUSEUM,DOWNING ST,CAMBRIDGE CB2 3EJ,ENGLAND.
NR 26
TC 70
Z9 75
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 392
EP 394
DI 10.1038/369392a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400054
DA 2026-03-10
ER

PT J
AU PINCUS, R
   BAKER, MB
AF PINCUS, R
   BAKER, MB
TI EFFECT OF PRECIPITATION ON THE ALBEDO SUSCEPTIBILITY OF CLOUDS IN THE MARINE BOUNDARY-LAYER
SO NATURE
LA English
DT Article
ID mixed layer; stratiform clouds; diurnal-variation; stratocumulus; aerosols; climate; model
AB TROPOSPHERIC aerosols are thought to have three important effects on the Earth's radiation budget: the direct radiative effect(1) (perturbation of clear-sky reflectivity), the indirect radiative effect(2) (modification of cloud albedo) and the effect on the hydrological cycle(3) (modification of the vertical thickness and horizontal extent of clouds). The first two effects have been understood in principle for nearly 20 years, and quantitative estimates of their magnitudes have been provided by models and observations(4). The third phenomenon, and its relation to the other two, has received far less attention. Previous work(3) has shown, however, that increases in aerosol concentration may act to increase cloud albedo by increasing horizontal cloud fraction as well as cloud reflectivity. Here we use a simple model of the marine cloud-topped boundary layer to investigate the changes in cloud thickness and albedo that result from changes in precipitation as particle concentrations vary. We find that the sensitivity of layer cloud albedo to droplet number concentration (the albedo susceptibility) is increased by 50-200% when the dependence of cloud thickness on particle number is included. The results suggest that the response of cloud thickness to changes in aerosol particle concentration must be taken into account for accurate prediction of global albedo by climate models.
RP PINCUS, R (corresponding author), UNIV WASHINGTON, GEOPHYS PROGRAM AK50, SEATTLE, WA 98195 USA.
NR 28
TC 269
Z9 332
U1 1
U2 42
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 250
EP 252
DI 10.1038/372250a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900045
DA 2026-03-10
ER

PT J
AU PINN, A
AF PINN, A
TI SCIENTISTS MOVING INTO SALES
SO NATURE
LA English
DT Article
RP PINN, A (corresponding author), DELTA CONSULTANTS,OLD COURTHOUSE,PRIORY RD,HUNTINGDON PE17 4BB,CAMBS,ENGLAND.
NR 0
TC 0
Z9 0
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 480
EP 480
DI 10.1038/368480a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000071
PM 8133897
DA 2026-03-10
ER

PT J
AU LYON, BE
   EADIE, JM
   HAMILTON, LD
AF LYON, BE
   EADIE, JM
   HAMILTON, LD
TI PARENTAL CHOICE SELECTS FOR ORNAMENTAL PLUMAGE IN AMERICAN COOT CHICKS
SO NATURE
LA English
DT Article
ID sexual selection; female choice; evolution; coloration; signals
AB ORNAMENTAL traits such as colourful bird plumage were the prime motivation for Darwin's theory of sexual selection(1). Other evolutionary mechanisms could also select for ornamental traits(2-6), but such mechanisms have received far less attention, and empirical evidence for their existence is weak. Here we show that parental choice selects for the bizarre ornamental plumes of newly hatched American coot (Fulica americana) chicks. Experimental manipulations of chick plumage revealed that parent coots feed ornamented chicks preferentially over non-ornamented chicks, resulting in higher growth rates and greater survival for ornamented chicks.
C1 UNIV TORONTO,DIV LIFE SCI,SCARBOROUGH M1C 1A4,ON,CANADA.
   UNIV CALGARY,FAC MED,CALGARY T2N 1N4,AB,CANADA.
C3 University of Toronto; University Toronto Scarborough; University of Calgary
NR 22
TC 128
Z9 138
U1 0
U2 56
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 240
EP 243
DI 10.1038/371240a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000050
DA 2026-03-10
ER

PT J
AU ZIEGLER, A
   JONASON, AS
   LEFFELL, DJ
   SIMON, JA
   SHARMA, HW
   KIMMELMAN, J
   REMINGTON, L
   JACKS, T
   BRASH, DE
AF ZIEGLER, A
   JONASON, AS
   LEFFELL, DJ
   SIMON, JA
   SHARMA, HW
   KIMMELMAN, J
   REMINGTON, L
   JACKS, T
   BRASH, DE
TI SUNBURN AND P53 IN THE ONSET OF SKIN-CANCER
SO NATURE
LA English
DT Article
ID ultraviolet radiation; solar keratoses; cell; sunlight; mutation; apoptosis; promotion; exposure; gene; dna
AB SQUAMOUS cell carcinoma of the skin (SCC) can progress by stages: sun-damaged epidermis, with individual disordered keratinocytes; actinic keratosis (AK), spontaneously regressing keratinized patches having aberrant cell differentiation and proliferation; carcinoma in situ; SCC and metastasis(1-3). To understand how sunlight acts as a carcinogen, we determined the stage at which sunlight mutates the p53 tumour-suppressor gene and identified a function for p53 in skin. The p53 mutations induced by ultraviolet radiation and found in >90% of human SCCs4,5 were present in AKs. Inactivating p53 in mouse skin reduced the appearance of sunburn cells(6), apoptotic keratinocytes generated by overexposure to ultraviolet. Skin thus appears to possess a p53-dependent 'guardian-of-the-tissue' response to DNA damage which aborts precancerous cells. If this response is reduced in a single cell by a prior p53 mutation, sunburn can select for clonal expansion of the p53-mutated cell into the AK. Sunlight can act twice: as tumour initiator and tumour promoter.
C1 YALE UNIV,SCH MED,DEPT DERMATOL,NEW HAVEN,CT 06510.
   YALE UNIV,SCH MED,DEPT GENET,NEW HAVEN,CT 06510.
   MIT,HOWARD HUGHES MED INST,CTR CANC RES,DEPT BIOL,CAMBRIDGE,MA 02139.
C3 Yale University; Yale University; Howard Hughes Medical Institute; Massachusetts Institute of Technology (MIT)
RP ZIEGLER, A (corresponding author), YALE UNIV,SCH MED,DEPT THERAPEUT RADIOL,NEW HAVEN,CT 06510, USA.
NR 30
TC 1280
Z9 1396
U1 0
U2 107
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 773
EP 776
DI 10.1038/372773a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200051
PM 7997263
DA 2026-03-10
ER

PT J
AU CONDIE, SA
   RHINES, PB
AF CONDIE, SA
   RHINES, PB
TI A CONVECTIVE MODEL FOR THE ZONAL JETS IN THE ATMOSPHERES OF JUPITER AND SATURN
SO NATURE
LA English
DT Article
ID great red spot; laboratory analog; vortices; circulations; simulation; stability; flow
AB THE atmospheres of Jupiter and Saturn are stably stratified in a region extending from the tropopause down to the level of the cloud tops; the underlying region is dominated by convective overturning1,2. Horizontal velocities within the stable region decrease with altitude3, suggesting that they are driven by momentum transfer from the deeper flow. But the vertical structure within the convective region is still poorly understood1. Its visible component at cloud level consists of alternating east-west zonal jets, with the more pronounced eastward jets attaining velocities in excess of 100 m s-1 and widths of about 10(4) km (refs 2 and 3). Here we propose a mechanism whereby the zonal jets result from convection cells resembling atmospheric Hadley cells on the Earth4. We demonstrate this mechanism using a rotating axisymmetric bowl of fluid, uniformly cooled at the free surface; radially overturning convection cells are established, the surface manifestation of which are pronounced azimuthal jets. A simple linear theory reproduces the main characteristics of the laboratory flow and predicts a relatively shallow penetration depth for the convection cells on Jupiter and Saturn.
C1 UNIV WASHINGTON,SCH OCEANOG WB10,SEATTLE,WA 98195.
C3 University of Washington; University of Washington Seattle
RP CONDIE, SA (corresponding author), AUSTRALIAN NATL UNIV,RES SCH EARTH SCI,CANBERRA,ACT 0200,AUSTRALIA.
NR 25
TC 40
Z9 42
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 711
EP 713
DI 10.1038/367711a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100049
DA 2026-03-10
ER

PT J
AU JACOBS, GA
   HURLBURT, HE
   KINDLE, JC
   METZGER, EJ
   MITCHELL, JL
   TEAGUE, WJ
   WALLCRAFT, AJ
AF JACOBS, GA
   HURLBURT, HE
   KINDLE, JC
   METZGER, EJ
   MITCHELL, JL
   TEAGUE, WJ
   WALLCRAFT, AJ
TI DECADE-SCALE TRANS-PACIFIC PROPAGATION AND WARMING EFFECTS OF AN EL-NINO ANOMALY
SO NATURE
LA English
DT Article
ID ocean response; temperatures; model
AB El Nino events in the Pacific Ocean can have significant local effects lasting up to two years. For example the 1982-83 El Nino caused increases in the sea-surface height and temperature at the coasts of Ecuador and Peru(1), with important consequences for fish populations(2,3) and local rainfall(4). But it has been believed that the long-range effects of El Nino events are restricted to changes transmitted through the atmosphere, for example causing precipitation anomalies over the Sahel(5). Here we present evidence from modelling and observations that planetary-scale oceanic waves, generated by reflection of equatorial shallow-water waves from the American coasts during the 1982-83 El Nino, have crossed the North Pacific and a decade later caused northward re-routing of the Kuroshio Extension-a strong current that normally advects large amounts of heat from the southern coast of Japan eastwards into the mid-latitude Pacific. This has led to significant increases in sea surface temperature at high latitudes in the northwestern Pacific, of the same amplitude and with the same spatial extent as those seen in the tropics during important El Nino events. These changes may have influenced weather patterns over the North American continent during the past decade, and demonstrate that the oceanic effects of El Nino events can be extremely long-lived.
C1 UNIV COLORADO,COLORADO CTR ASTRODYNAM RES,BOULDER,CO 80303.
   PLANNING SYST INC,BAY ST LOUIS,MS 39529.
C3 University of Colorado System; University of Colorado Boulder
RP JACOBS, GA (corresponding author), USN,RES LAB,BAY ST LOUIS,MS 39529, USA.
NR 25
TC 206
Z9 220
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 360
EP 363
DI 10.1038/370360a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400052
DA 2026-03-10
ER

PT J
AU LOPATIN, AN
   MAKHINA, EN
   NICHOLS, CG
AF LOPATIN, AN
   MAKHINA, EN
   NICHOLS, CG
TI POTASSIUM CHANNEL BLOCK BY CYTOPLASMIC POLYAMINES AS THE MECHANISM OF INTRINSIC RECTIFICATION
SO NATURE
LA English
DT Article
ID guinea-pig heart; inward rectification; ventricular cells; magnesium block; expression; membrane; myocytes; cloning; mg-2+
AB INWARDLY rectifying potassium channels conduct ions more readily in the inward than the outward direction, an essential property for normal electrical activity(1,2). Although voltage-dependent block by internal magnesium ions may underlie inward rectification in some channels(3-5), an intrinsic voltage-dependent closure of the channel plays a contributory, or even exclusive, role in others(4,6-9). Here me report that, rather than being intrinsic to the channel protein, so-called intrinsic rectification of strong inward rectifiers requires soluble factors that are not Mg2+ and can be released from Xenopus oocytes and other cells. Biochemical and biophysical characterization identifies these factors as polyamines (spermine, spermidine, putrescine and cadaverine). The results suggest that intrinsic rectification results from voltage-dependent block of the channel pore by polyamines, not from a voltage sensor intrinsic to the channel protein(10).
C1 WASHINGTON UNIV,SCH MED,DEPT CELL BIOL & PHYSIOL,ST LOUIS,MO 63110.
C3 Washington University (WUSTL)
NR 30
TC 754
Z9 852
U1 0
U2 22
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 366
EP 369
DI 10.1038/372366a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700057
PM 7969496
DA 2026-03-10
ER

PT J
AU TSE, JS
   KLUG, DD
   RIPMEESTER, JA
   DESGRENIERS, S
   LAGAREC, K
AF TSE, JS
   KLUG, DD
   RIPMEESTER, JA
   DESGRENIERS, S
   LAGAREC, K
TI THE ROLE OF NON-DEFORMABLE UNITS IN PRESSURE-INDUCED REVERSIBLE AMORPHIZATION OF CLATHRASILS
SO NATURE
LA English
DT Article
ID induced phase-transformations; metallic amorphous state; mechanical instability; molecular-dynamics; crystal-structure; ice; quartz; glass; sio2; dodecasil-3c
AB PRESSURE-induced amorphization of solids has been much studied since it was first observed in 1984(1). It was found recently(2,3) that some materials can be amorphized reversibly under pressure, reverting back to the original crystalline structure and orientation when the pressure is decreased. It has been suggested(4) that the presence of non-deformable units is essential for this reversibility, these units acting as templates around which the original structure is reformed. Here we investigate this idea by comparing the effect of pressure on two clathrasils-silica solids with open, microporous structures-with and without guest molecules inside the pores. We have studied pressure-induced amorphization of dodecasil-3C, which has cage-like voids, and dodecasil-3R, which has two-dimensional channels. For both materials, our experiments and simulations show that amorphization is fully or partly reversible only when guest molecules are present suggesting that these do indeed act as rigid 'organizing centres' for the reversible transformation.
C1 UNIV OTTAWA,DEPT PHYS,OTTAWA K1N 6N5,ON,CANADA.
C3 University of Ottawa
RP TSE, JS (corresponding author), NATL RES COUNCIL CANADA,STEACIE INST MOLEC SCI,100 SUSSEX DR,OTTAWA K1A 0R6,ON,CANADA.
NR 36
TC 80
Z9 83
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 724
EP 727
DI 10.1038/369724a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100052
DA 2026-03-10
ER

PT J
AU LIU, L
   STEVENSON, SB
   SCHOR, CM
AF LIU, L
   STEVENSON, SB
   SCHOR, CM
TI QUANTITATIVE STEREOSCOPIC DEPTH WITHOUT BINOCULAR CORRESPONDENCE
SO NATURE
LA English
DT Article
ID occluding contours; illusory contours; stereopsis; rivalry; capture
AB WHAT features in a stereogram define the disparities that lead to stereoscopic depth? The usual answer is that luminance-defined edges from the two eyes are matched and produce depth perception1,2. But parts of an object may be occluded by other objects and absent from one eye's view. It was suggested that unpaired monocular elements might signal occlusion in depth, and the qualitative perception of depth associated with unmatched elements has, been shown to be consistent with the geometry of occlusion3-5.  We designed a stereogram that simulates a particular occlusion situation: an opaque white rectangle is stereoscopically in front of a large black rectangle pasted on a white background. The position of the occluder is adjusted so that its left edge obscures the left-hand edge of the black rectangle in the right eye view and its right edge obscures the right-hand edge of the black rectangle in the left eye view. We report here that quantitative stereopsis can be seen from this stereogram, even though there are no binocular corresponding luminance edges to match.
RP LIU, L (corresponding author), UNIV CALIF BERKELEY,SCH OPTOMETRY,BERKELEY,CA 94720, USA.
NR 14
TC 47
Z9 49
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 66
EP 69
DI 10.1038/367066a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500060
PM 8107776
DA 2026-03-10
ER

PT J
AU BEYERS, R
   KIANG, CH
   JOHNSON, RD
   SALEM, JR
   DEVRIES, MS
   YANNONI, CS
   BETHUNE, DS
   DORN, HC
   BURBANK, P
   HARICH, K
   STEVENSON, S
AF BEYERS, R
   KIANG, CH
   JOHNSON, RD
   SALEM, JR
   DEVRIES, MS
   YANNONI, CS
   BETHUNE, DS
   DORN, HC
   BURBANK, P
   HARICH, K
   STEVENSON, S
TI PREPARATION AND STRUCTURE OF CRYSTALS OF THE METALLOFULLERENE SC-2-AT-C-84
SO NATURE
LA English
DT Article
ID electron-microscopy; ground-state; c-60; isomers; fullerenes; carbon; c84
AB IT was first proposed in 1985(1) that fullerenes can confine atoms in their interior because of their closed-cage structure. Attempts to verify this conjecture following the mass production of fullerenes(2,3) have yielded metallofullerenes in bulk, and there is now good evidence that these compounds are endohedral(4)-that is, that the metal atoms are inside. But direct confirmation in the form of structural data has been lacking, in part because of the difficulty of separating different metallofullerenes and obtaining pure crystals. Here we report the preparation of pure crystalline Sc-2@C-84 and analyses of its structure by electron diffraction and high-resolution transmission electron microscopy. At room temperature the Sc-2@C-84 molecules pack in a hexagonal-close-packed structure with a ratio of lattice constants c/a = 1.63, the value expected for ideal-sphere packing. The molecular spacing of 11.2 Angstrom is the same as that found earlier in crystalline C-84 (refs 5,6). The match between our microscopic images and simulations is markedly better for endohedral models than for those in which the metal atoms reside in the lattice outside the C-84 cages. We believe that this combination of observations points inevitably to the conclusion that the metal atoms are inside the fullerenes.
C1 CALTECH,CTR MAT & MOLEC STIMULAT,BECKMAN INST,PASADENA,CA 91125.
   VIRGINIA POLYTECH INST & STATE UNIV,DEPT CHEM,BLACKSBURG,VA 24061.
C3 California Institute of Technology; Virginia Polytechnic Institute & State University
RP BEYERS, R (corresponding author), IBM CORP,ALMADEN RES CTR,DIV RES,650 HARRY RD,SAN JOSE,CA 95120, USA.
NR 25
TC 115
Z9 116
U1 0
U2 22
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 196
EP 199
DI 10.1038/370196a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100044
DA 2026-03-10
ER

PT J
AU FEI, YJ
   KANAI, Y
   NUSSBERGER, S
   GANAPATHY, V
   LEIBACH, FH
   ROMERO, MF
   SINGH, SK
   BORON, WF
   HEDIGER, MA
AF FEI, YJ
   KANAI, Y
   NUSSBERGER, S
   GANAPATHY, V
   LEIBACH, FH
   ROMERO, MF
   SINGH, SK
   BORON, WF
   HEDIGER, MA
TI EXPRESSION CLONING OF A MAMMALIAN PROTON-COUPLED OLIGOPEPTIDE TRANSPORTER
SO NATURE
LA English
DT Article
ID na+ glucose cotransporter; border membrane-vesicles; beta-lactam antibiotics; glycyl-l-proline; small-intestine; rabbit; ph; specificity; absorption; cdna
AB IN mammals, active transport of organic solutes across plasma membranes was thought to be primarily driven by the Na+ gradient1-3. Here we report the cloning and functional characterization of a H+-coupled transporter of oligopeptides and peptide-derived antibiotics from rabbit small intestine. This new protein, named PepT1, displays an unusually broad substrate specificity. PepT1-mediated uptake is electrogenic, independent of extracellular Na+, K+ and Cl-, and of membrane potential. PepT1 messenger RNA was found in intestine, kidney and liver and in small amounts in brain. In the intestine, the PepT1 pathway constitutes a major mechanism for absorption of the products of protein digestion. To our knowledge, the PepT1 primary structure is the first reported for a proton-coupled organic solute transporter in vertebrates and represents an interesting evolutionary link between prokaryotic H+-coupled and vertebrate Na+-coupled transporters of organic solutes.
C1 BRIGHAM & WOMENS HOSP,DEPT MED,DIV RENAL,75 FRANCIS ST,BOSTON,MA 02115.
   HARVARD UNIV,SCH MED,DEPT BIOL CHEM & MOLEC PHARMACOL,BOSTON,MA 02115.
   MED COLL GEORGIA,DEPT BIOCHEM & MOLEC BIOL,AUGUSTA,GA 30912.
   YALE UNIV,SCH MED,DEPT CELLULAR & MOLEC PHYSIOL,NEW HAVEN,CT 06510.
C3 Harvard University; Harvard University Medical Affiliates; Brigham & Women's Hospital; Harvard University; Harvard Medical School; University System of Georgia; Augusta University; Yale University
FU NIDDK NIH HHS [F32 DK009342] Funding Source: Medline
NR 30
TC 765
Z9 843
U1 1
U2 61
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 563
EP 566
DI 10.1038/368563a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500060
PM 8139693
DA 2026-03-10
ER

PT J
AU RETTIG, J
   HEINEMANN, SH
   WUNDER, F
   LORRA, C
   PARCEJ, DN
   DOLLY, JO
   PONGS, O
AF RETTIG, J
   HEINEMANN, SH
   WUNDER, F
   LORRA, C
   PARCEJ, DN
   DOLLY, JO
   PONGS, O
TI INACTIVATION PROPERTIES OF VOLTAGE-GATED K+ CHANNELS ALTERED BY PRESENCE OF BETA-SUBUNIT
SO NATURE
LA English
DT Article
ID potassium channels; rat-brain; functional expression; dendrotoxin acceptor; binding-property; molecular-biology; xenopus oocytes; ik(a) channels; ion channels; bovine brain
AB Structural and functional diversity of voltage-gated K(v)1-type potassium channels in rat brain is enhanced by the association of two different types of subunits, the membrane-bound, pore-forming alpha-subunits and a peripheral beta-subunit. We have cloned a beta-subunit (K-v beta 1) that is specifically expressed in the rat nervous system. Association of K-v beta 1 with alpha-subunits confers rapid A-type inactivation on non-inactivating K(v)1 channels (delayed rectifiers) in expression systems in vitro. This effect is mediated by an inactivating ball domain in the K-v beta 1 amino terminus.
C1 MAX PLANCK INST BIOPHYS CHEM,MEMBRANBIOPHYS ABT,D-37077 GOTTINGEN,GERMANY.
   MAX PLANCK GESELL ZFDW,AG MOLEK & ZELLULARE BIOPHYS,D-07747 JENA,GERMANY.
   UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED,DEPT BIOCHEM,WOLFSON LABS,LONDON SW7 2AY,ENGLAND.
C3 Max Planck Society; Max Planck Society; Imperial College London
RP RETTIG, J (corresponding author), ZENTRUM MOLEK NEUROBIOL HAMBURG,INST NEURALE SIGNALVERARBEITUNG,MARTINISTR 52,D-20246 HAMBURG,GERMANY.
NR 43
TC 777
Z9 853
U1 0
U2 51
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 289
EP 294
DI 10.1038/369289a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900039
PM 8183366
DA 2026-03-10
ER

PT J
AU LOK, S
   KAUSHANSKY, K
   HOLLY, RD
   KUIJPER, JL
   LOFTONDAY, CE
   OORT, PJ
   GRANT, FJ
   HEIPEL, MD
   BURKHEAD, SK
   KRAMER, JM
   BELL, LA
   SPRECHER, CA
   BLUMBERG, H
   JOHNSON, R
   PRUNKARD, D
   CHING, AFT
   MATHEWES, SL
   BAILEY, MC
   FORSTROM, JW
   BUDDLE, MM
   OSBORN, SG
   EVANS, SJ
   SHEPPARD, PO
   PRESNELL, SR
   OHARA, PJ
   HAGEN, FS
   ROTH, GJ
   FOSTER, DC
AF LOK, S
   KAUSHANSKY, K
   HOLLY, RD
   KUIJPER, JL
   LOFTONDAY, CE
   OORT, PJ
   GRANT, FJ
   HEIPEL, MD
   BURKHEAD, SK
   KRAMER, JM
   BELL, LA
   SPRECHER, CA
   BLUMBERG, H
   JOHNSON, R
   PRUNKARD, D
   CHING, AFT
   MATHEWES, SL
   BAILEY, MC
   FORSTROM, JW
   BUDDLE, MM
   OSBORN, SG
   EVANS, SJ
   SHEPPARD, PO
   PRESNELL, SR
   OHARA, PJ
   HAGEN, FS
   ROTH, GJ
   FOSTER, DC
TI CLONING AND EXPRESSION OF MURINE THROMBOPOIETIN CDNA AND STIMULATION OF PLATELET PRODUCTION IN-VIVO
SO NATURE
LA English
DT Article
ID factor receptor superfamily; molecular-cloning; c-mpl; growth; megakaryocytopoiesis; sequence; member; identification; protooncogene; interleukin-6
AB THE major regulator of circulating platelet levels is believed to be a cytokine termed thrombopoietin(1,2). It is thought to be a lineage-specific cytokine affecting the proliferation and maturation of committed cells resulting in the production of megakaryocytes and platelets. Despite considerable efforts by a number of laboratories, the unequivocal identification of thrombopoietin has proven elusive. Here we report the functional cloning of a murine complementarg DNA encoding a ligand for the receptor encoded by the c-mpl proto-oncogene (c-Mpl)3-5. The encoded polypeptide has a predicted molecular mass of 35,000 (M(r) 35K). The protein has a novel two-domain structure with an amino-terminal domain homologous with erythropoietin and a carboxy-terminal domain rich in serine, threonine and proline residues and containing seven potential N-linked glycosylation sites. Intraperitoneal injections of mice with recombinant protein increase circulating platelet levels by greater than fourfold after 7 days. These results along with those presented in the accompanying report strongly suggest that the ligand for c-Mpl is thrombopoietin.
C1 ZYMOGENET INC,SEATTLE,WA 98105.
   UNIV WASHINGTON,SCH MED,DIV HEMATOL,SEATTLE,WA 98195.
C3 Zymogenet Inc.; University of Washington; University of Washington Seattle
NR 27
TC 1031
Z9 1103
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 565
EP 568
DI 10.1038/369565a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400051
PM 8202158
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI THE WORLDS BIGGEST URBAN EXPERIMENT
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 802
EP 802
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700036
DA 2026-03-10
ER

PT J
AU OCONNOR, JJ
   ROWAN, MJ
   ANWYL, R
AF OCONNOR, JJ
   ROWAN, MJ
   ANWYL, R
TI LONG-LASTING ENHANCEMENT OF NMDA RECEPTOR-MEDIATED SYNAPTIC TRANSMISSION BY METABOTROPIC GLUTAMATE-RECEPTOR ACTIVATION
SO NATURE
LA English
DT Article
ID term potentiation; trans-acpd; trans-1-aminocyclopentane-1,3-dicarboxylic acid; rat hippocampus; currents; slices; cells; responses; agonist
AB SYNAPTIC transmission mediated by the N-methyl-D-aspartate (NMDA) glutamate receptor plays a key role in a range of plastic processes in the nervous system. These include long-term potentiation of synaptic transmission mediated by the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor, neuronal development, excitotoxicity and certain learning tasks1,2. Recently, long-term potentiation of NMDA receptor-mediated synaptic transmission was found to occur following high-frequency (tetanic) stimulation via an unknown mechanism3-7. We show here that activation of metabotropic glutamate (mGlu) receptors by neurally released transmitter underlies this type of long-term potentiation. The whole-cell patch-clamp technique in the 'thick' slice of the rat dentate gyrus was used to measure NMDA receptor-mediated excitatory postsynaptic currents. We have found that mGlu receptor activation by a selective agonist produced a long-lasting enhancement which was mutually exclusive with long-term potentiation of these NMDA currents. Moreover, both forms of potentiation were greatly reduced by the mGlu receptor antagonists L-2-amino-3-phosphonopropionate and (R,S)-alpha-methyl-4-carboxyphenylglycine.
C1 UNIV DUBLIN TRINITY COLL, DEPT PHARMACOL & THERAPEUT, DUBLIN 2, IRELAND.
   UNIV DUBLIN TRINITY COLL, DEPT PHYSIOL, DUBLIN 2, IRELAND.
C3 Trinity College Dublin; Trinity College Dublin
FU Wellcome Trust Funding Source: Medline
NR 24
TC 164
Z9 175
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 557
EP 559
DI 10.1038/367557a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300058
PM 7906392
DA 2026-03-10
ER

PT J
AU KELLER, LF
   ARCESE, P
   SMITH, JNM
   HOCHACHKA, WM
   STEARNS, SC
AF KELLER, LF
   ARCESE, P
   SMITH, JNM
   HOCHACHKA, WM
   STEARNS, SC
TI SELECTION AGAINST INBRED SONG SPARROWS DURING A NATURAL-POPULATION BOTTLENECK
SO NATURE
LA English
DT Article
ID inbreeding depression; great tit; consequences; mortality
AB THE genetic and demographic consequences of population subdivision have received considerable attention from conservation biologists. In particular, losses of genetic variability and reduced viability and fecundity due to inbreeding (inbreeding depression) are of concern(1-3). Studies of domestic, laboratory(4,5) and zoo populations(2,6,7) have shown inbreeding depression in a variety of traits related to fitness. Consequently, inbreeding depression is widely accepted as a fact. Recently, however, the relative impact of inbreeding on the viability of natural populations has been questioned(8-10). Work on the cheetah (Acinonyx jubatus), for example, has emphasized the overwhelming importance of environmental factors on mortality in the wild(9,10). Here we report that song sparrows (Melospiza melodia) that survived a severe population bottleneck were a non-random subset of the pre-crash population with respect to inbreeding, and that natural selection favoured outbred individuals. Thus, inbreeding depression was expressed in the face of an environmental challenge. Such challenges are also likely to be faced by inbred populations of endangered species. We suggest that environmental and genetic effects on survival may interact and, as a consequence, that their effects on individuals and populations should not be considered independently.
C1 UNIV BRITISH COLUMBIA,DEPT ZOOL,VANCOUVER V6T 1Z4,BC,CANADA.
   UNIV BASEL,INST ZOOL,CH-4051 BASEL,SWITZERLAND.
C3 University of British Columbia; University of Basel
RP KELLER, LF (corresponding author), UNIV WISCONSIN,DEPT WILDLIFE ECOL,1630 LINDEN DR,MADISON,WI 53706, USA.
NR 29
TC 320
Z9 347
U1 0
U2 109
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 356
EP 357
DI 10.1038/372356a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700053
PM 7969492
DA 2026-03-10
ER

PT J
AU YANG, YD
   BLAKE, R
AF YANG, YD
   BLAKE, R
TI BROAD TUNING FOR SPATIAL-FREQUENCY OF NEURAL MECHANISMS UNDERLYING VISUAL-PERCEPTION OF COHERENT MOTION
SO NATURE
LA English
DT Article
AB NEURAL events underlying perception of coherent motion are generally believed to be hierarchical(1,2): information about local motion is registered by spatio-temporal coincidence detectors(3-5) whose outputs are cooperatively integrated at a subsequent stage(6,7). There is disagreement, however, concerning the spatial scale of the neural filters underlying these operations. According to one class of models, motion registration is initially accomplished in parallel at multiple spatial scales(3-5), with filters tuned to lower spatial frequencies responsive to larger motion displacements than filters tuned to higher frequencies. According to another scheme, motion analysis involves a single, broadly tuned spatial filter, with optimal displacement dependent on spacing of local elements(8). Here we use a masking procedure to measure the extent to which dynamic noise depicted at one spatial scale interferes with detection of coherent motion conveyed by image features at another spatial scale. Our results indicate that a single filter, broadly tuned for spatial frequency, is mediating detection of coherent motion. This finding dovetails with known physiological properties of neurons at an intermediate stage of motion processing.
RP YANG, YD (corresponding author), VANDERBILT UNIV,DEPT PSYCHOL,NASHVILLE,TN 37240, USA.
NR 19
TC 35
Z9 35
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 793
EP 796
DI 10.1038/371793a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800058
PM 7935839
DA 2026-03-10
ER

PT J
AU BAILEY, RC
AF BAILEY, RC
TI FLUID TRAPPING IN MIDCRUSTAL RESERVOIRS BY H2O-CO2 MIXTURES
SO NATURE
LA English
DT Article
ID continental-crust; aqueous fluids; deep crust; pressures; water; immiscibility; metamorphism; temperatures; reflection; transport
AB A THIN reservoir of free aqueous or carbonic fluids at mid-crustal levels, perhaps in the form of water sills(1), has been suggested as the source of fault-transmitted metasomatizing fluids(2-4), as the cause of observed deep crustal electrical conductivity and anomalous seismic reflectivity(5), and as a lubricated potential detachment zone for thin-skin tectonics(6). A problem with this hypothesis is that estimated crustal permeabilities are too high to permit long-term retention of such fluids(7,8). Most mechanisms suggested for achieving the required permeability reduction rely on maintaining unusually low porosity(2,6,9,10). Because porosity creation, by tectonic deformation, fluid release or infiltration, is a ubiquitous process, permeability reductions achieved by these mechanisms are hard to sustain for long periods of time. A sealing (permeability reduction) mechanism that can operate in the presence of significant porosity is required. Here I propose that the required mechanism is capillary sealing by immiscible CO2-H2O mixtures derived from rising volatiles.
C1 UNIV TORONTO,DEPT PHYS,TORONTO M5S 1A7,ON,CANADA.
C3 University of Toronto
RP BAILEY, RC (corresponding author), UNIV TORONTO,DEPT GEOL,TORONTO M5S 1A7,ON,CANADA.
NR 31
TC 25
Z9 26
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 238
EP 240
DI 10.1038/371238a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000049
DA 2026-03-10
ER

PT J
AU DENG, TL
   KARIN, M
AF DENG, TL
   KARIN, M
TI C-FOS TRANSCRIPTIONAL ACTIVITY STIMULATED BY H-RAS-ACTIVATED PROTEIN-KINASE DISTINCT FROM JNK AND ERK
SO NATURE
LA English
DT Article
ID cell-proliferation; tyrosine kinases; jun activity; map kinases; phosphorylation; domain; receptor; complex; expression; oncogenes
AB RAS proteins exert their mitogenic and oncogenic effects through activation of downstream protein kinases(1). An important question is how Ras-generated signals reach the nucleus to activate downstream target genes. AP-1, a heterodimeric complex of Jun and Fos proteins, which activates mitogen-inducible genes(2), is a major nuclear target of Ras(3). Ras can stimulate AP-1 activity by inducing c-fos transcription(2,3), a process which is probably mediated by the ERK1 and -2 mitogen-activated protein (MAP) kinases(4), which phosphorylate the transcription factor Elk-1/TCF5,6. Besides inducing transcription from fos and jun genes, mitogens and Ras proteins enhance AP-1 activity through phosphorylation of c-Jun(7,8). Phosphorylation of the c-Jun activation domain leads to c-jun induction through an autoregulatory loop(2). Ras- and ultraviolet-responsive protein kinases that phosphorylate c-Jun on serine residues at positions 63 and 73 and stimulate its transcriptional activity have been identified(9). These proline-directed kinases, termed JNKs, are novel MAP kinases(10). It is not clear, however, whether c-Jun is the only recipient and JNK the only transducer of the Ras signal to AP-1 proteins, A short sequence surrounding the major JNK phosphorylation site of c-Jun is conserved in c-Fos and is part of its activation domain(11), suggesting that c-Fos may be similarly regulated. Here we show that Ras does indeed augment the transcriptional activity of c-Fos through phosphorylation at Thr 232, the homologue of Ser 73 of c-Jun. However, this is mediated by a novel Ras- and mitogen-responsive proline-directed protein kinase that is different from JNKs and ERKs. Therefore, at least three types of proline-directed kinases(4) transmit Ras- and mitogen-generated signals to the transcriptional machinery.
C1 UNIV CALIF SAN DIEGO, SCH MED, CTR MOLEC GENET, DEPT PHARMACOL, LA JOLLA, CA 92093 USA.
C3 University of California System; University of California San Diego
NR 41
TC 334
Z9 366
U1 0
U2 1
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 171
EP 175
DI 10.1038/371171a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100068
PM 8072547
DA 2026-03-10
ER

PT J
AU YOON, HS
   HAJDUK, PJ
   PETROS, AM
   OLEJNICZAK, ET
   MEADOWS, RP
   FESIK, SW
AF YOON, HS
   HAJDUK, PJ
   PETROS, AM
   OLEJNICZAK, ET
   MEADOWS, RP
   FESIK, SW
TI SOLUTION STRUCTURE OF A PLECKSTRIN-HOMOLOGY DOMAIN
SO NATURE
LA English
DT Article
ID nuclear-magnetic-resonance; binding-protein; 3-dimensional structure; n-15-labeled proteins; distance geometry; crystal-structure; chemical-shifts; c-alpha; kinase; nmr
AB Pleckstrin(1), the major protein kinase C substrate of platelets, contains domains of about 100 amino acids at the amino and carboxy termini that have been found in a number of proteins, including serine/threonine kinases, GTPase-activating proteins, phospholipases and cytoskeletal proteins(2-5). These conserved sequences, termed pleckstrin-homology (PH) domains, are thought to be involved in signal transduction. But the details of the function and binding partners of the PH domains have not been characterized. Here we report the solution structure of the N-terminal pleckstrin-homology domain of pleckstrin determined using heteronuclear three-dimensional nuclear magnetic resonance spectroscopy. The structure consists of an up-and-down beta-barrel of seven antiparallel beta-strands and a C-terminal amphiphilic alpha-helix that caps one end of the barrel. The overall topology of the domain is similar to that of the retinol-binding protein family of structures(6-10).
C1 ABBOTT LABS,DIV PHARMACEUT DISCOVERY,ABBOTT PK,IL 60064.
C3 Abbott Laboratories
NR 30
TC 202
Z9 219
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 672
EP 675
DI 10.1038/369672a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900062
PM 8208296
DA 2026-03-10
ER

PT J
AU CREMER, H
   LANGE, R
   CHRISTOPH, A
   PLOMANN, M
   VOPPER, G
   ROES, J
   BROWN, R
   BALDWIN, S
   KRAEMER, P
   SCHEFF, S
   BARTHELS, D
   RAJEWSKY, K
   WILLE, W
AF CREMER, H
   LANGE, R
   CHRISTOPH, A
   PLOMANN, M
   VOPPER, G
   ROES, J
   BROWN, R
   BALDWIN, S
   KRAEMER, P
   SCHEFF, S
   BARTHELS, D
   RAJEWSKY, K
   WILLE, W
TI INACTIVATION OF THE N-CAM GENE IN MICE RESULTS IN SIZE-REDUCTION OF THE OLFACTORY-BULB AND DEFICITS IN SPATIAL-LEARNING
SO NATURE
LA English
DT Article
ID cell-adhesion molecule; neural development; polysialic acid; dentate gyrus; mutant mice; adult-rat; ncam; expression; mouse; plasticity
AB NEURAL-CELL adhesion molecules (N-CAMs) are members of the immunoglobulin superfamily mediating homo- and heterophilic cell-cell interactions. N-CAM exists in various isoforms which are generated by alternative splicing1-3. During embryonic development, N-CAMs are expressed in derivatives of all three germ layers, whereas in the adult animal they are predominantly present in neural tissue. Processes like neurulation4, axonal outgrowth5, histogenesis of the retina6,7 and development of the olfactory system8-10 are correlated with the regulated expression of N-CAMs11-14. We show here that N-CAM-deficient mice generated by gene targeting appear healthy and fertile, but adult mutants show a 10% reduction in overall brain weight and a 36% decline in size of the olfactory bulb. N-CAM deficiency coincides with almost total loss of protein-bound alpha-(2,8)-linked polysialic acid, a carbohydrate structure thought to be correlated with neural development and plasticity15,16. The animals showed deficits in spatial learning when tested in the Morris water maze17, whereas activity and motor abilities appeared normal.
C1 UNIV COLOGNE,INST GENET,D-50931 COLOGNE,GERMANY.
   UNIV KENTUCKY,SANDERS BROWN CTR AGING,LEXINGTON,KY 40536.
C3 University of Cologne; University of Kentucky
RP CREMER, H (corresponding author), UNIV COLOGNE,INST GENET,ZULPICHER STR 47,D-50674 COLOGNE,GERMANY.
NR 30
TC 902
Z9 982
U1 0
U2 21
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 455
EP 459
DI 10.1038/367455a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900053
PM 8107803
DA 2026-03-10
ER

PT J
AU SLAGSVOLD, T
   AMUNDSEN, T
   DALE, S
AF SLAGSVOLD, T
   AMUNDSEN, T
   DALE, S
TI SELECTION BY SEXUAL CONFLICT FOR EVENLY SPACED OFFSPRING IN BLUE TITS
SO NATURE
LA English
DT Article
ID hatching asynchrony; nestling weight; clutch size; survival; brood; blackbird; behavior; quality; birds; parus
AB IN animals with parental care, parents rearing offspring of variable ages are typically assumed to exert less effort than those rearing even-aged offspring. This is because spaced births spread out peak loads in the combined food demands of all offspring(1-3). Creating a mixed-size sibship also helps establish a hierarchy among the young which reduces the costs of sibling rivalry(4) and can help efficient elimination of young if food becomes short(5,6). We manipulated hatching spread within broods of the blue tit Parus caeruleus and studied postbreeding survival rate of the adults. We report here that, contrary to current,theory, female parents suffer less when the young are even-aged than when they are of variable ages, whereas the opposite result was found for male parents. Apparently, the male contributes more in synchronous broods, thus lightening the female's total investment burden. In blue tits this sexual conflict over hatching pattern is won by the female because she alone incubates. By delaying incubation until most eggs have been laid, she reduces hatching span.
C1 UNIV TRONDHEIM,DEPT ZOOL,N-7055 DRAGVOLL,NORWAY.
RP SLAGSVOLD, T (corresponding author), UNIV OSLO,DEPT BIOL,POB 1050,N-0316 OSLO 3,NORWAY.
NR 29
TC 60
Z9 62
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 136
EP 138
DI 10.1038/370136a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400055
DA 2026-03-10
ER

PT J
AU GRAZIANO, V
   GERCHMAN, SE
   SCHNEIDER, DK
   RAMAKRISHNAN, V
AF GRAZIANO, V
   GERCHMAN, SE
   SCHNEIDER, DK
   RAMAKRISHNAN, V
TI HISTONE H1 IS LOCATED IN THE INTERIOR OF THE CHROMATIN 30-NM FILAMENT
SO NATURE
LA English
DT Article
ID higher-order structure; globular domain; rna genes; transcription; accessibility; organization; antibody; fragments; exchange; fiber
AB THE linker histone H1 binds to the nucleosome and is essential for the organization of nucleosomes into the 30-nm filament of chromatin(1). It has been implicated in the repression of transcription(2,5), and phosphorylation of H1 may be involved in cell-cycle-dependent chromatin condensation and decondensation(6). A long-standing issue concerns the location of H1 in the chromatin filament(7). The original solenoidal model(8) proposes that H1 is inside the 30-nm filament, but other models, also helical, suggest a variable(9) or more accessible(10) location for H1. Investigations to determine the location of the linker histone based on its accessibility to antibodies(11-15) or immobilized proteases(16) under various ionic conditions have yielded conflicting results. Here we use neutron scattering in a direct structural determination to show that H1 is located in the interior of the filament.
C1 BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973.
C3 United States Department of Energy (DOE); Brookhaven National Laboratory
NR 29
TC 100
Z9 112
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 351
EP 354
DI 10.1038/368351a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500051
PM 8127372
DA 2026-03-10
ER

PT J
AU GOTZ, R
   KOSTER, R
   WINKLER, C
   RAULF, F
   LOTTSPEICH, F
   SCHARTL, M
   THOENEN, H
AF GOTZ, R
   KOSTER, R
   WINKLER, C
   RAULF, F
   LOTTSPEICH, F
   SCHARTL, M
   THOENEN, H
TI NEUROTROPHIN-6 IS A NEW MEMBER OF THE NERVE GROWTH-FACTOR FAMILY
SO NATURE
LA English
DT Article
ID embryonic-development; sensory neurons; cell-surface; identification; survival; cleavage; proteins; receptor; binding; biology
AB DURING vertebrate development, many neurons depend for survival and differentiation on their target cells(1-3). The best documented mediator of such a retrograde trophic action is the neurotrophin nerve growth factor (NGF)(1). NGF and the other known members of the neurotrophin family, brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and neurotrophin-4/5 (NT-4/5) are conserved as distinct genes over large evolutionary distances(4-6). Here we report the cloning of neurotrophin-6 (NT-6), a new member of this family from the teleost fish Xiphophorus. NT-6 distinguishes itself from the other known neurotrophins in that it is not found as a soluble protein in the medium of producing cells. The addition of heparin (but not chondroitin) effects the release of NT-6 from cell surface and extracellular matrix molecules. Recombinant purified NT-6 has a spectrum of actions similar to NGF on chick sympathetic and sensory neurons, albeit with a lower potency. NT-6 is expressed in the embryonic valvulla cerebelli; expression persists in some adult tissues. The interaction of NT-6 with heparin-binding molecules may modulate its action in the nervous system.
C1 MAX PLANCK INST PSYCHIAT,DEPT NEUROCHEM,D-82152 MARTINSRIED,GERMANY.
   UNIV WURZBURG,BIOZENTRUM,DEPT PHYSIOL CHEM 1,D-97074 WURZBURG,GERMANY.
   MAX PLANCK INST BIOCHEM,D-82152 MARTINSRIED,GERMANY.
C3 Max Planck Society; University of Wurzburg; Max Planck Society
NR 30
TC 344
Z9 414
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 266
EP 269
DI 10.1038/372266a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900051
PM 7969471
DA 2026-03-10
ER

PT J
AU MARKUS, M
   KLOSS, G
   KUSCH, I
AF MARKUS, M
   KLOSS, G
   KUSCH, I
TI DISORDERED WAVES IN A HOMOGENEOUS, MOTIONLESS EXCITABLE MEDIUM
SO NATURE
LA English
DT Article
ID belousov-zhabotinsky reaction; spiral breakup; cellular automaton; model; turbulence; curvature; systems; fronts
AB EXCITABLE media are physical, chemical or biological systems in which energy dissipation in disturbed regions is compensated by energy supply(1-4), so that the media can support waves without attenuation. Well-known examples are nervous tissue, heart muscle, retinae, aggregating amoebae and the autocatalytic Belousov-Zhabotinsky (BZ) reaction. Most familiar in such systems are periodic target and spiral waves, but a number of simulations(5-11) have suggested that disordered waves can also occur in a homogenous and motionless excitable medium. In all experimental observations reported so far, however, hydrodynamic flow(12,13) or inhomogeneities(14,15) were necessary to induce disorder. Here we present experimental evidence for disordered chemical waves in a convection-free and homogeneous medium, a gel containing a light-sensitive BZ reaction mixture. We find instabilities transverse to the wavefront ('ripples'), wave breakup leading to aperiodic spiral formation, labyrinthine structures, and erratic motion of non-spiralling wave fragments. The formal analogy of the BZ reagent with other excitable media suggests that this disordered behaviour may be generic.
RP MARKUS, M (corresponding author), MAX PLANCK INST MOLEK PHYSIOL,POSTFACH 102664,D-44026 DORTMUND,GERMANY.
NR 28
TC 72
Z9 74
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 402
EP 404
DI 10.1038/371402a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500037
DA 2026-03-10
ER

PT J
AU KUROKAWA, R
   DIRENZO, J
   BOEHM, M
   SUGARMAN, J
   GLOSS, B
   ROSENFELD, MG
   HEYMAN, RA
   GLASS, CK
AF KUROKAWA, R
   DIRENZO, J
   BOEHM, M
   SUGARMAN, J
   GLOSS, B
   ROSENFELD, MG
   HEYMAN, RA
   GLASS, CK
TI REGULATION OF RETINOID SIGNALING BY RECEPTOR POLARITY AND ALLOSTERIC CONTROL OF LIGAND-BINDING
SO NATURE
LA English
DT Article
ID thyroid-hormone; x-receptor; response elements; nuclear receptor; dna-binding; direct repeat; amino-acids; beta-gene; rxr-beta; rar
AB RETINOIC acid receptors (RARs) and retinoid X receptors (RXRs) regulate transcription by binding to response elements in target genes that generally consist of two direct repeat half-sites of consensus sequence AGGTCA (ref. 1). RAR/RXR heterodimers activate transcription in response to all-irans or 9-cis retinoic acid by binding to direct repeats spaced by five base pairs (DR5 elements)(2-8), such that RAR occupies the downstream half-site(9-12). RXR homodimers activate transcription in response to 9-cis retinoic acid by binding to direct repeats spaced by one base pair (DR1 elements)(8,13,14). Although RXR/RAR heterodimers bind to DR1 elements with higher affinity than RXR homodimers, in most contexts they are unable to activate transcription in response to either all-trans or 9-cis retinoic acid(3-5). AS a result, RARs inhibit RXR-dependent transcription from these sites(13,15). We report that the switching of the RAR from an activator to an inhibitor of retinoid-dependent transcription requires that it be bound to the upstream half-site of DR1 elements and that it allosterically block the binding of ligand to the RXR.
C1 UNIV CALIF SAN DIEGO,DIV CELLULAR & MOLEC MED,LA JOLLA,CA 92093.
   UNIV CALIF SAN DIEGO,DIV ENDOCRINOL & METAB,LA JOLLA,CA 92093.
   UNIV CALIF SAN DIEGO,HOWARD HUGHES MED INST,LA JOLLA,CA 92093.
   LIGAND PHARMACEUT,DEPT CELL BIOL,SAN DIEGO,CA 92121.
C3 University of California System; University of California San Diego; University of California System; University of California San Diego; Howard Hughes Medical Institute; University of California System; University of California San Diego; Ligand Pharmaceuticals
NR 26
TC 396
Z9 443
U1 1
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 528
EP 531
DI 10.1038/371528a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900059
PM 7935766
DA 2026-03-10
ER

PT J
AU PAILLARD, D
   LABEYRIE, L
AF PAILLARD, D
   LABEYRIE, L
TI ROLE OF THE THERMOHALINE CIRCULATION IN THE ABRUPT WARMING AFTER HEINRICH EVENTS
SO NATURE
LA English
DT Article
ID north-atlantic ocean; greenland ice; climate; records; core
AB EVIDENCE of rapid climate oscillations during the last glacial period has been identified in climate records from Greenland ice cores(1,2) and ocean sediments in the North Atlantic(3,4). These records show that periods of gradual cooling are terminated by abrupt warming events(5), with the coldest periods coinciding with the deposition of ice-rafted debris (so-called Heinrich events) throughout the North Atlantic. Heinrich events are thought to be a signature of massive iceberg discharges owing to collapse of the Laurentide ice sheet; Bond et al.(5) have proposed that the decrease in meltwater flux following collapse and retreat of the ice sheet enhanced the ocean's thermohaline circulation: thereby increasing advection of heat from the tropics and giving rise to abrupt climate warming. Here we test this idea using a simple ocean model coupled to a model of a periodically surging ice sheet. We find that massive discharges of icebergs first stop the thermohaline circulation because of the consequent freshwater influx, cooling the North Atlantic region. This is followed by a rapid restart of the circulation, leading to abrupt warming. Thus our model can reproduce the qualitative features of the climate oscillations seen in the ice-core and ocean records.
C1 CEA,CNRS,CFR LAB MIXTE,F-91198 GIF SUR YVETTE,FRANCE.
C3 CEA; Centre National de la Recherche Scientifique (CNRS); Universite Paris Saclay
RP PAILLARD, D (corresponding author), CE SACLAY,CEA,DSM,MODELISAT CLIMAT & ENVIRONM LAB,F-91191 GIF SUR YVETTE,FRANCE.
NR 23
TC 97
Z9 104
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 162
EP 164
DI 10.1038/372162a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800050
DA 2026-03-10
ER

PT J
AU COLLINGE, J
   WHITTINGTON, MA
   SIDLE, KCL
   SMITH, CJ
   PALMER, MS
   CLARKE, AR
   JEFFERYS, JGR
AF COLLINGE, J
   WHITTINGTON, MA
   SIDLE, KCL
   SMITH, CJ
   PALMER, MS
   CLARKE, AR
   JEFFERYS, JGR
TI PRION PROTEIN IS NECESSARY FOR NORMAL SYNAPTIC FUNCTION
SO NATURE
LA English
DT Article
ID intrahippocampal tetanus toxin; long-term potentiation; rat; hippocampus; invitro; depression; induction; receptor; disease
AB THE prion diseases are neurodegenerative conditions, transmissible by inoculation, and in some cases inherited as an autosomal dominant disorder. They include Creutzfeldt-Jakob disease in humans and scrapie and bovine spongiform encephalopathy in animals. The prion consists principally of a post-translationally modified form of a host-encoded glycoprotein (PrPc), designated PrPSc (ref. 1); the normal cellular function of PrPc is, however, unknown. Although PrP is highly conserved among mammals and widely expressed in early embryogenesis, mice homozygous for disrupted PrP genes appear developmentally and behaviourally normal(2). PrP is a protein anchored to the neuronal surface by glycosylphosphatidylinositol, suggesting a role in cell signalling or adhesion. Here we report that hippocampal slices from PrP null mice have weakened GABA(A) (gamma-aminobutyric acid type A) receptor-mediated fast inhibition and impaired long-term potentiation. This impaired synaptic inhibition may be involved in the epileptiform activity seen in Creutzfeldt-Jakob disease and we argue that loss of function of PrPc may contribute to the early synaptic loss(3) and neuronal degeneration seen in these diseases.
C1 ST MARYS HOSP,SCH MED,DEPT PHYSIOL & BIOPHYS,LONDON W2 1PG,ENGLAND.
   ST MARYS HOSP,DEPT NEUROL,LONDON W2 1NY,ENGLAND.
   UNIV BRISTOL,SCH MED SCI,DEPT BIOCHEM,BRISTOL BS8 1TD,ENGLAND.
C3 Imperial College London; Imperial College London; University of Bristol
RP COLLINGE, J (corresponding author), ST MARYS HOSP,SCH MED,DEPT BIOCHEM & MOLEC GENET,PRION DIS GRP,LONDON W2 1PG,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 23
TC 675
Z9 740
U1 1
U2 52
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 295
EP 297
DI 10.1038/370295a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900064
PM 8035877
DA 2026-03-10
ER

PT J
AU SEEWALD, JS
AF SEEWALD, JS
TI EVIDENCE FOR METASTABLE EQUILIBRIUM BETWEEN HYDROCARBONS UNDER HYDROTHERMAL CONDITIONS
SO NATURE
LA English
DT Article
ID petroleum; minerals; systems; gases; oil
AB THERMAL maturation of organic matter in sedimentary basins results in the generation of numerous organic alteration products. These products influence the chemical and physical alteration processes of sediments(1-3), and in some instances their accumulation results in the formation of oil and natural-gas deposits(4,5). Much uncertainty exists about the factors that control the relative abundances of individual organic species during maturation. Although it is clear that kinetic barriers allow thermodynamically unstable species to persist in a metastable state for geologically significant periods of time, local equilibrium between more-reactive species may substantially influence their abundance. Here I report the results of redox-buffered hydrothermal experiments designed to investigate reactions that may occur in geological environments between ethane, ethene, water and inorganic redox-sensitive minerals. I find that reversible metastable thermodynamic equilibrium is attained between these species. Because water participates directly in this equilibrium, it may represent a reactive and abundant source of hydrogen for hydrocarbon generation in sedimentary basins. This demonstration that metastable equilibrium is attained implies that some organic geochemical reactions can be thermodynamically modelled and predicted despite the absence of total thermodynamic equilibrium.
RP SEEWALD, JS (corresponding author), WOODS HOLE OCEANOG INST,WOODS HOLE,MA 02543, USA.
NR 31
TC 183
Z9 215
U1 2
U2 34
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 285
EP 287
DI 10.1038/370285a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900060
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI INDUSTRIALISTS FACING THE NAFTA FACTS
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 803
EP 804
DI 
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700037
DA 2026-03-10
ER

PT J
AU BROECKER, WS
AF BROECKER, WS
TI MASSIVE ICEBERG DISCHARGES AS TRIGGERS FOR GLOBAL CLIMATE-CHANGE
SO NATURE
LA English
DT Article
ID ice-core; heinrich events; atlantic-ocean; glacial period; greenland ice; k-ar; sediments; record; isotope
AB Observations of large and abrupt climate changes recorded in Greenland ice cores have spurred a search for clues to their cause. This search has revealed that at six times during the last glaciation, huge armadas of icebergs launched from Canada spread across the northern Atlantic Ocean, each triggering a climate response of global extent.
RP BROECKER, WS (corresponding author), COLUMBIA UNIV, LAMONT DOHERTY GEOL OBSERV, ROUTE 9W, PALISADES, NY 10964 USA.
NR 45
TC 637
Z9 745
U1 5
U2 163
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 421
EP 424
DI 10.1038/372421a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200045
DA 2026-03-10
ER

PT J
AU MILLER, DM
   GOLDSTEIN, SL
   LANGMUIR, CH
AF MILLER, DM
   GOLDSTEIN, SL
   LANGMUIR, CH
TI CERIUM LEAD AND LEAD-ISOTOPE RATIOS IN ARC MAGMAS AND THE ENRICHMENT OF LEAD IN THE CONTINENTS
SO NATURE
LA English
DT Article
ID trace-element constraints; island-arc; mantle evolution; sr isotopes; chemical-structure; oceanic basalts; lesser antilles; volcanic-rocks; pb; plumes
AB Lead is anomalously enriched in the Earth's continental crust, and in the magmas that give rise to new continental crust at convergent margins. A detailed study of volcanic rocks from the Aleutian island arc shows that this enrichment is a continuing process, and results from the efficient non-magmatic transfer of mantle-derived lead into the source of convergent-margin magmas. This process, acting through time, can also account for the pervasive depletion of lead in the oceanic mantle.
C1 COLUMBIA UNIV, PALISADES, NY 10964 USA.
   MAX PLANCK INST CHEM, D-55020 MAINZ, GERMANY.
C3 Columbia University; Max Planck Society
RP MILLER, DM (corresponding author), COLUMBIA UNIV, LAMONT DOHERTY GEOL OBSERV, PALISADES, NY 10964 USA.
NR 64
TC 352
Z9 384
U1 1
U2 34
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 514
EP 520
DI 10.1038/368514a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500044
DA 2026-03-10
ER

PT J
AU TURNER, RE
   RABALAIS, NN
AF TURNER, RE
   RABALAIS, NN
TI COASTAL EUTROPHICATION NEAR THE MISSISSIPPI RIVER DELTA
SO NATURE
LA English
DT Article
ID water; silica; marine; nutrient; hypoxia; trends
AB CHANGES in delivery of river-borne nutrients such as dissolved Phosphate, nitrate and silicate, owing to land-use changes and anthropogenic emissions, are known to result in eutrophication1-enhanced phytoplankton blooms-and more severe hypoxic events2-4 in many enclosed bays and seas, Although similar ecological effects might be expected on continental shelves, the occurrence of such eutrophication has remained unresolved5. Here we present evidence of eutrophication of the continental shelf near the outflow of the Mississippi river, obtained by quantifying biologically bound silica (BSi) in diatom remnants within dated sediment cores. BSi accumulation rates are greatest in water depths of 20 to 50 m within 100 km of the river mouth, and have increased by as much as 100% this century. The increases were substantial by 1980, by which time riverine nitrogen loading had doubled relative to the beginning of the century, even though the silica loading had declined by 50% over the same period. Thus changes in river-borne nutrient loadings can modify coastal food webs and affect the amount and distribution of oxygen in bottom waters on the scale of continental shelves.
C1 LOUISIANA STATE UNIV,INST COASTAL ECOL,BATON ROUGE,LA 70803.
   LOUISIANA UNIV MARINE CONSORTIUM,CHAUVIN,LA 70344.
C3 Louisiana State University System; Louisiana State University
RP TURNER, RE (corresponding author), LOUISIANA STATE UNIV,DEPT OCEANOG & COASTAL SCI,BATON ROUGE,LA 70803, USA.
NR 22
TC 615
Z9 748
U1 1
U2 200
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 619
EP 621
DI 10.1038/368619a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200055
DA 2026-03-10
ER

PT J
AU KARL, DM
   TILBROOK, BD
AF KARL, DM
   TILBROOK, BD
TI PRODUCTION AND TRANSPORT OF METHANE IN OCEANIC PARTICULATE ORGANIC-MATTER
SO NATURE
LA English
DT Article
ID upper water column; north pacific; surface waters; fluxes; atlantic; carbon
AB METHANE is an important component of the global carbon cycle(1) and a potent greenhouse gas(2,3). Surface ocean waters are typically supersaturated with dissolved methane relative to atmospheric equilibrium, presumably as a result of in situ microbial methane production(4-8). Because methanogenic bacteria are strict anaerobes(9) and surface ocean waters are highly oxygenated, the observation of methane supersaturation has been termed the 'oceanic methane paradox'(10). Although methanogenic bacteria have been isolated from oceanic particulate matter, faecal pellets and zooplankton(11-14), no data are available on in situ rates of methane formation in these microenvironments. During a series of experiments in the North Pacific ocean, we have identified a previously unrecognized component of the oceanic methane cycle. We find that methane is associated with sinking particles, presumably as a dissolved constituent of the interstitial fluids of particulate biogenic materials, which exchanges with the water column as particles sink. This phenomenon provides a mechanism for the active transport in the water column of an otherwise passive, dissolved species. The particle-to-seawater methane flux that we measure is sufficient to replace all of the methane present in the upper water column in about 50 days and to produce the characteristic methane supersaturations in less than a month. We suggest that particulate production and transport may also be relevant to the redistribution and cycling of other bioreactive compounds in the marine environment.
C1 CSIRO,DIV OCEANOG,HOBART,TAS 7001,AUSTRALIA.
C3 Commonwealth Scientific & Industrial Research Organisation (CSIRO)
RP KARL, DM (corresponding author), UNIV HAWAII,SCH OCEAN & EARTH SCI & TECHNOL,DEPT OCEANOG,HONOLULU,HI 96822, USA.
NR 26
TC 187
Z9 216
U1 1
U2 68
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 732
EP 734
DI 10.1038/368732a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300055
DA 2026-03-10
ER

PT J
AU OTTAWAY, TL
   WICKS, FJ
   BRYNDZIA, LT
   KYSER, TK
   SPOONER, ETC
AF OTTAWAY, TL
   WICKS, FJ
   BRYNDZIA, LT
   KYSER, TK
   SPOONER, ETC
TI FORMATION OF THE MUZO HYDROTHERMAL EMERALD DEPOSIT IN COLOMBIA
SO NATURE
LA English
DT Article
ID cordillera
AB FOR over 1,000 years, the emerald deposits of Colombia have been the principal source of the world's largest and finest gem-quality emeralds-a variety of beryl containing chromium and vanadium(1). Whereas most emerald deposits are found in association with igneous host rocks(1), the Colombian deposits occur in organic-rich black shales, and their origin in the absence of any evidence of igneous activity has been a persistent enigma. Here we present evidence from the Muzo mine (located about 100 km from Bogota) that hydrothermal brines transported evaporitic sulphate to structurally favourable sites, where it was thermochemically reduced. We suggest that the sulphur generated by this process reacted with organic matter in the shales to release trapped chromium, vanadium and beryllium, which in turn enabled emerald formation.
C1 UNIV SASKATCHEWAN,DEPT GEOL SCI,SASKATOON S7N 0W0,SK,CANADA.
   UNIV TORONTO,DEPT GEOL,TORONTO M5S 3B1,ON,CANADA.
C3 University of Saskatchewan; University of Toronto
RP OTTAWAY, TL (corresponding author), ROYAL ONTARIO MUSEUM,DEPT MINERAL,100 QUEENS PK,TORONTO M5S 2C6,ON,CANADA.
NR 19
TC 82
Z9 102
U1 1
U2 38
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 552
EP 554
DI 10.1038/369552a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400046
DA 2026-03-10
ER

PT J
AU ASSENHEIMER, M
   STEINBERG, V
AF ASSENHEIMER, M
   STEINBERG, V
TI TRANSITION BETWEEN SPIRAL AND TARGET STATES IN RAYLEIGH-BENARD CONVECTION
SO NATURE
LA English
DT Article
ID thermal-convection; excitable media; patterns; instability
AB RAYLEIGH-BENARD convection1-4, which occurs when a shallow fluid layer is heated from below, is commonly regarded as a paradigm for pattern formation under non-equilibrium conditions. The formation of hexagonal arrays of Benard cells is well known, but more complex patterns such as targets5 and spirals5-11 have also been reported. Similar patterns have been seen in electrohydrodynamical convection12,13, oscillatory chemical reactions14-19 and biological systems19,20. In general, the spiral and target states are found for different experimental conditions. Here we report the observation of a continuous transition between states containing many spirals and many targets, in a fluid undergoing Rayleigh-Benard convection near the gas-liquid critical point. Whether spirals or targets are observed depends on the Prandtl number, the ratio between the thermal and viscous timescales in the fluid. Neither of these states seems to be predicted by the hydrodynamic equations that describe the fluid motions1-4, 21. The fact that the transformation of one pattern into the other is continuous, and that under some conditions they can coexist, suggests that they may be generated by the same or a similar mechanism.
RP ASSENHEIMER, M (corresponding author), WEIZMANN INST SCI,DEPT PHYS COMPLEX SYST,IL-76100 REHOVOT,ISRAEL.
NR 25
TC 100
Z9 105
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 345
EP 347
DI 10.1038/367345a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000059
DA 2026-03-10
ER

PT J
AU ZHENG, JQ
   FELDER, M
   CONNOR, JA
   POO, MM
AF ZHENG, JQ
   FELDER, M
   CONNOR, JA
   POO, MM
TI TURNING OF NERVE GROWTH CONES INDUCED BY NEUROTRANSMITTERS
SO NATURE
LA English
DT Article
ID protein kinase-ii; intracellular calcium; neurite elongation; acetylcholine-receptors; identified neurons; guidance; motility; serotonin; culture; axons
AB PATHFINDING by growing nerve processes in the developing nervous system depends on the turning response of the growing tip, the growth cone, to extracellular guidance cues(1-4). There is evidence in vivo and in cell culture that some growth cones exhibit chemotropic behaviour(5-12), but the identity of endogenous chemoattractants remains elusive. Neurotransmitters appear early in the developing embryo and may have morphogenic roles in development(13,14). In cell culture a number of neurotransmitters were found to induce growth inhibition or retraction of neurites(15-19). Here we report positive turning responses of the nerve growth cone in a defined extracellular gradient of the neurotransmitter acetylcholine (ACh). The growth cone response depends on the activation of neuronal nicotinic ACh receptors, requires the presence of extracellular Ca2+, and appears to be mediated by Ca2+-calmodulin-dependent protein kinase II. Fluorescence imaging of cytosolic Ca2+ concentration ([Ca2+](i)) at the growth cone showed a small but significant evaluation of [Ca2+](i) within minutes of the onset of ACh application and before the turning of the growth cone. These findings suggest that neurotransmitters may serve as specific chemoattractants for growth cone guidance and that cytosolic Ca2+ may act as a second messenger in the cytoplasm of the growth cone to initiate the turning response.
C1 COLUMBIA UNIV, DEPT BIOL SCI, NEW YORK, NY 10027 USA.
   ROCHE RES CTR, ROCHE INST MOLEC BIOL, NUTLEY, NJ 07110 USA.
C3 Columbia University; Roche Holding; Roche Holding USA
FU NIGMS NIH HHS [R01 GM083889] Funding Source: Medline
NR 40
TC 518
Z9 576
U1 0
U2 11
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 140
EP 144
DI 10.1038/368140a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000064
PM 8139655
DA 2026-03-10
ER

PT J
AU EVERETT, M
   LAL, A
   GORDON, D
   CLAYTON, CE
   MARSH, KA
   JOSHI, C
AF EVERETT, M
   LAL, A
   GORDON, D
   CLAYTON, CE
   MARSH, KA
   JOSHI, C
TI TRAPPED ELECTRON ACCELERATION BY A LASER-DRIVEN RELATIVISTIC PLASMA-WAVE
SO NATURE
LA English
DT Article
ID excitation
AB THE aim of new approaches for high-energy particle acceleration1 is to push the acceleration rate beyond the limit (approximately 100 MeV m-1) imposed by radio-frequency breakdown in conventional accelerators. Relativistic plasma waves, having phase velocities very close to the speed of light, have been proposed2-6 as a means of accelerating charged particles, and this has recently been demonstrated7,8. Here we show that the charged particles can be trapped by relativistic plasma waves-a necessary condition for obtaining the maximum amount of energy theoretically possible for such schemes. In our experiments, plasma waves are excited in a hydrogen plasma by beats induced by two collinear laser beams, the difference in whose frequencies matches the plasma frequency. Electrons with an energy of 2 MeV are injected into the excited plasma, and the energy spectrum of the exiting electrons is analysed. We detect electrons with velocities exceeding that of the plasma wave, demonstrating that some electrons are 'trapped' by the wave potential and therefore move synchronously with the plasma wave. We observe a maximum energy gain of 28 MeV, corresponding to an acceleration rate of about 2.8 GeV m-1.
RP EVERETT, M (corresponding author), UNIV CALIF LOS ANGELES,DEPT ELECT ENGN,LOS ANGELES,CA 90024, USA.
NR 19
TC 130
Z9 141
U1 0
U2 26
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 527
EP 529
DI 10.1038/368527a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500047
DA 2026-03-10
ER

PT J
AU HANNUM, C
   CULPEPPER, J
   CAMPBELL, D
   MCCLANAHAN, T
   ZURAWSKI, S
   BAZAN, JF
   KASTELEIN, R
   HUDAK, S
   WAGNER, J
   MATTSON, J
   LUH, J
   DUDA, G
   MARTINA, N
   PETERSON, D
   MENON, S
   SHANAFELT, A
   MUENCH, M
   KELNER, G
   NAMIKAWA, R
   RENNICK, D
   RONCAROLO, MG
   ZLOTNIK, A
   ROSNET, O
   DUBREUIL, P
   BIRNBAUM, D
   LEE, F
AF HANNUM, C
   CULPEPPER, J
   CAMPBELL, D
   MCCLANAHAN, T
   ZURAWSKI, S
   BAZAN, JF
   KASTELEIN, R
   HUDAK, S
   WAGNER, J
   MATTSON, J
   LUH, J
   DUDA, G
   MARTINA, N
   PETERSON, D
   MENON, S
   SHANAFELT, A
   MUENCH, M
   KELNER, G
   NAMIKAWA, R
   RENNICK, D
   RONCAROLO, MG
   ZLOTNIK, A
   ROSNET, O
   DUBREUIL, P
   BIRNBAUM, D
   LEE, F
TI LIGAND FOR FLT3 FLK2 RECEPTOR TYROSINE KINASE REGULATES GROWTH OF HEMATOPOIETIC STEM-CELLS AND IS ENCODED BY VARIANT RNAS
SO NATURE
LA English
DT Article
ID colony-stimulating factor; mouse
AB THE FLT3/FLK2 receptor tyrosine kinase is closely related to two receptors, c-Kit and c-Fms, which function with their respective ligands, Kit ligand and macrophage colony-stimulating factor to control differentiation of haematopoietic and non-haematopoietic cells1-5. FLT3/FLK2 is thought to be present on haematopoietic stem cells and found in brain, placenta and testis3-5. We have purified to homogeneity and partially sequenced a soluble form of the FLT3/FLK2 ligand produced by mouse thymic stromal cells. We isolated several mouse and human complementary DNAs that encode polypeptide with identical N termini and different C termini. Some variants contain hydrophobic transmembrane segments, suggesting that processing may be required to release soluble ligand. The purified ligand enhances the response of mouse stem cells and a primitive human progenitor cell population to other growth factors such as interleukins IL-3 and IL-6 and to granulocyte-macrophage colony-stimulating factor, and also stimulates fetal thymocytes.
C1 INSERM, U119, F-13009 MARSEILLE, FRANCE.
C3 Institut National de la Sante et de la Recherche Medicale (Inserm)
RP HANNUM, C (corresponding author), DNAX RES INST MOLEC & CELLULAR BIOL INC, 901 CALIF AVE, PALO ALTO, CA 94304 USA.
NR 21
TC 419
Z9 490
U1 0
U2 20
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 643
EP 648
DI 10.1038/368643a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200063
PM 8145851
DA 2026-03-10
ER

PT J
AU NOBRE, AC
   ALLISON, T
   MCCARTHY, G
AF NOBRE, AC
   ALLISON, T
   MCCARTHY, G
TI WORD RECOGNITION IN THE HUMAN INFERIOR TEMPORAL-LOBE
SO NATURE
LA English
DT Article
ID positron emission tomography; cortex; cells; face
AB STUDIES of primates(1) and of patients with brain lesions(2) have shown that the visual system represents the external world in regions and pathways specialized to compute visual features and attributes. For example, object recognition is performed by a ventral pathway located in the inferior portion of the temporal lobe(3). We studied visual processing of words and word-like stimuli (letter-strings) by recording held potentials directly from the human inferior temporal lobe. Our results showed that two discrete portions of the fusiform gyrus responded preferentially to letter-strings. A region of the posterior fusiform gyrus responded equally to words and nonwords, and was unaffected by the semantic context in which words were presented. In contrast, a region of the anterior fusiform gyrus was sensitive to these stimulus dimensions. These regions were distinct from areas that responded to other types of complex visual stimuli, including faces and coloured patterns, and thus form a functionally specialized stream within the ventral visual pathway.
C1 VET ADM MED CTR,NEUROPSYCHOL LAB,W HAVEN,CT 06516.
   YALE UNIV,SCH MED,DEPT NEUROL,NEW HAVEN,CT 06510.
   YALE UNIV,SCH MED,NEUROSURG SECT,NEW HAVEN,CT 06510.
C3 US Department of Veterans Affairs; Veterans Health Administration (VHA); VA Connecticut Healthcare System; Yale University; Yale University
NR 29
TC 654
Z9 726
U1 0
U2 34
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 260
EP 263
DI 10.1038/372260a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900049
PM 7969469
DA 2026-03-10
ER

PT J
AU ISHIKAWA, T
   NAKAMURA, E
AF ISHIKAWA, T
   NAKAMURA, E
TI ORIGIN OF THE SLAB COMPONENT IN ARC LAVAS FROM ACROSS-ARC VARIATION OF B AND PB ISOTOPES
SO NATURE
LA English
DT Article
ID subduction processes; southwest japan; volcanic-rocks; systematics; geochemistry; basalts; magmatism; genesis; element; pacific
AB AT convergent margins, the subducting oceanic slab is thought to dehydrate, producing fluids which metasomatize the overlying mantle wedge where island-are magma forms. However, the nature and origin of the metasomatizing fluid, its source composition and its relation to the genesis of the chemical characteristics of are magmas are largely controversial. Across-are variation in the chemistry of are lavas provides a useful key to this problem, because it may reflect the changes in the physical conditions of the subducting slab that control mass transfer from slab to mantle wedge as a function of depth. Here we report clear across-are variations in the concentrations and isotopic compositions of boron and lead observed in lavas from the Izu arc (Japan). Our data suggest that a homogeneous slab fluid contributes to all Izu volcanoes, but that the amount of this fluid decreases continuously with increasing depth of the subducting slab. Whereas the Izu slab fluid comes primarily from altered oceanic crust, our data for high-Mg andesites from the Setouchi volcanic belt (a nearby fore-arc) indicate a significant involvement of sediment in the fluid source.
C1 OKAYAMA UNIV,INST STUDY EARTHS INTERIOR,PHEASANT MEM LAB,MISASA 68201,TOTTORI,JAPAN.
C3 Okayama University
NR 31
TC 338
Z9 367
U1 1
U2 60
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 205
EP 208
DI 10.1038/370205a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100048
DA 2026-03-10
ER

PT J
AU TSUKIYAMA, T
   BECKER, PB
   WU, C
AF TSUKIYAMA, T
   BECKER, PB
   WU, C
TI ATP-DEPENDENT NUCLEOSOME DISRUPTION AT A HEAT-SHOCK PROMOTER MEDIATED BY BINDING OF GAGA TRANSCRIPTION FACTOR
SO NATURE
LA English
DT Article
ID tumor virus promoter; drosophila-melanogaster; chromatin structure; gene; proteins; dna; complex; activation; encodes; extracts
AB Genetic control elements are usually situated in local regions of chromatin that are hypersensitive to structural probes such as DNase I. We have reconstructed the chromatin structure of the hsp70 promoter using an in vitro nucleosome assembly system. Binding of the GAGA transcription factor on existing nucleosomes leads to nucleosome disruption, DNase I hypersensitivity at the TATA box and heat-shock elements, and rearrangement of adjacent nucleosomes. ATP hydrolysis facilitates this process, suggesting that an energy-dependent pathway is involved in chromatin remodelling.
C1 NCI,BIOCHEM LAB,BLDG 37,ROOM 4C-09,BETHESDA,MD 20892.
C3 National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI)
NR 51
TC 587
Z9 640
U1 0
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 525
EP 532
DI 10.1038/367525a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300049
PM 8107823
DA 2026-03-10
ER

PT J
AU GOLDSTEIN, SJ
   PERFIT, MR
   BATIZA, R
   FORNARI, DJ
   MURRELL, MT
AF GOLDSTEIN, SJ
   PERFIT, MR
   BATIZA, R
   FORNARI, DJ
   MURRELL, MT
TI OFF-AXIS VOLCANISM AT THE EAST PACIFIC RISE DETECTED BY URANIUM-SERIES DATING OF BASALTS
SO NATURE
LA English
DT Article
ID mid-ocean ridges; magnetic-anomaly; spreading centers; midocean ridges; melt extraction; gorda ridges; beneath; evolution; juan; fuca
AB RECENT detailed surveys of the East Pacific Rise have revealed the complexity of the volcanic and magmatic processes occurring along and across fast-spreading ocean ridge crests1-7. In parallel with geological and geochemical investigations, it is now possible to investigate the temporal and spatial pattern of volcanism at ocean ridges by dating young basalts using mass spectrometric uranium-series disequilibria methods8-11. Here we use U-238-Th-230 and  U-235-Pa-231 ages for basalts to quantify the spatial extent of young volcanism and crustal accretion at 9-degrees 31' N on the East Pacific Rise. Most of the ages are younger than would be expected based on off-axis distance and spreading rate. We infer from these anomalously young ages that most of the dated basalts on the crestal plateau were erupted 0.5-2 km outside the axial summit caldera, with some volcanism occurring as far as 4 km off-axis. Melts erupted outside the axial summit caldera can have crustal residence times and magmatic supply systems that differ from those of axial lavas.
C1 UNIV FLORIDA,DEPT GEOL,GAINESVILLE,FL 32611.
   UNIV HAWAII,SCH OCEAN & EARTH SCI & TECHNOL,HONOLULU,HI 96822.
   COLUMBIA UNIV,LAMONT DOHERTY EARTH OBSERV,PALISADES,NY 10964.
C3 State University System of Florida; University of Florida; University of Hawaii System; Columbia University
RP GOLDSTEIN, SJ (corresponding author), LOS ALAMOS NATL LAB,MS K484,LOS ALAMOS,NM 87545, USA.
NR 33
TC 84
Z9 90
U1 1
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 157
EP 159
DI 10.1038/367157a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000055
DA 2026-03-10
ER

PT J
AU SURRIDGE, C
AF SURRIDGE, C
TI SHORTING OUT THE CELLULAR BATTERY
SO NATURE
LA English
DT Article
ID colicin-a
AB A low-resolution structure of the bacterial toxin collicin Ia provides a model for its lethal membrane association and an explanation for the anomalous behaviour of its C-terminal peptide fragment.
NR 5
TC 1
Z9 1
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 84
EP 84
DI 10.1038/371084a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100058
PM 8072534
DA 2026-03-10
ER

PT J
AU DELONG, EF
   WU, KY
   PREZELIN, BB
   JOVINE, RVM
AF DELONG, EF
   WU, KY
   PREZELIN, BB
   JOVINE, RVM
TI HIGH ABUNDANCE OF ARCHAEA IN ANTARCTIC MARINE PICOPLANKTON
SO NATURE
LA English
DT Article
ID microbial ecology; ribosomal-rna; diversity; archaebacteria; evolution
AB ARCHAEA (archaebacteria) constitute one of the three major evolutionary lineages of life on Earth(1-3). Previously these prokaryotes were thought to predominate in only a few unusual and disparate niches, characterized by hypersaline, extremely hot, or strictly anoxic conditions(4-7). Recently, novel (uncultivated) phylotypes of Archaea have been detected in coastal(8) and subsurface(9,10) marine waters, but their abundance, distribution, physiology and ecology remain largely undescribed. Here we report exceptionally high archaeal abundance in frigid marine surface waters of Antarctica. Pelagic Archaea constituted up to 34% of the prokaryotic biomass in coastal Antarctic surface waters, and they were also abundant in a variety of other cold, pelagic marine environments. Because they can make up a significant fraction of picoplankton biomass in the vast habitats encompassed by cold and deep marine waters, these pelagic Archaea represent an unexpectedly abundant component of the Earth's biota.
RP DELONG, EF (corresponding author), UNIV CALIF SANTA BARBARA,DEPT BIOL,DIV ECOL EVOLUT & MARINE BIOL,SANTA BARBARA,CA 93106, USA.
NR 24
TC 429
Z9 480
U1 2
U2 68
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 695
EP 697
DI 10.1038/371695a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300053
PM 7935813
DA 2026-03-10
ER

PT J
AU GARCIAFERNANDEZ, J
   HOLLAND, PWH
AF GARCIAFERNANDEZ, J
   HOLLAND, PWH
TI ARCHETYPAL ORGANIZATION OF THE AMPHIOXUS HOX GENE-CLUSTER
SO NATURE
LA English
DT Article
ID homeobox-containing genes; caenorhabditis-elegans; vertebrate evolution; expression; metazoan; family; mouse
AB ORGANIZATION into gene clusters is an essential and diagnostic feature of Hox genes(1). Insect and nematode genomes possess single Hox gene clusters (split in Dvosophila); in mammals, there are 38 Hox genes in four clusters on different chromosomes(2,3). A collinear relationship between chromosomal position, activation time and anterior expression limit of vertebrate Hox genes suggests that clustering may be important for precise spatiotemporal gene regulation and hence embryonic patterning(2,4). Hox genes have a wide phylogenetic distribution within the metazoa, and are implicated in the control of regionalization along the anteroposterior body axis(2,5). It has been suggested that changes in Hox gene number and genomic organization played a role in metazoan body-plan evolution(6-8), but identifying significant changes is difficult because Hox gene organization is known from only very few and widely divergent taxa (principally insects, nematodes and vertebrates)(3). Here we analyse the complexity and organization of Hox genes in a cephalochordate, amphioxus, the taxon thought to be the sister group of the vertebrates(9). We find that the amphioxus genome has only one Hox gene cluster. It has similar genomic organization to the four mammalian Hox clusters, and contains homologues of at least the first ten paralogous groups of vertebrate Hox genes in a collinear array. Remarkably, this organization is compatible with that inferred for a direct ancestor of the vertebrates; we conclude; that amphioxus is a living representative of a critical intermediate stage in Hox cluster evolution.
C1 UNIV OXFORD,DEPT ZOOL,OXFORD OX1 3PS,ENGLAND.
C3 University of Oxford
NR 29
TC 485
Z9 519
U1 2
U2 49
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 563
EP 566
DI 10.1038/370563a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700057
PM 7914353
DA 2026-03-10
ER

PT J
AU ZHANG, FM
   STRAND, A
   ROBBINS, D
   COBB, MH
   GOLDSMITH, EJ
AF ZHANG, FM
   STRAND, A
   ROBBINS, D
   COBB, MH
   GOLDSMITH, EJ
TI ATOMIC-STRUCTURE OF THE MAP KINASE ERK2 AT 2.3-ANGSTROM RESOLUTION
SO NATURE
LA English
DT Article
ID signal-regulated kinases; dependent protein-kinase; adenosine-monophosphate; catalytic subunit; growth-factor; substrate recognition; phosphorylation; insulin; activation; tyrosine
AB The structure of the MAP kinase ERK2, a ubiquitous protein kinase target for regulation by Ras and Raf, has been solved in its unphosphorylated low-activity conformation to a resolution of 2.3 angstrom. The two domains of unphosphorylated ERK2 are farther apart than in the active conformation of cAMP-dependent protein kinase and the peptide-binding site is blocked by tyrosine 185, one of the two residues that are phosphorylated in the active enzyme. Activation of ERK2 is thus likely to involve both global and local conformational changes.
C1 UNIV TEXAS,SW MED CTR,DEPT BIOCHEM,DALLAS,TX 75235.
   UNIV TEXAS,SW MED CTR,DEPT PHARMACOL,DALLAS,TX 75235.
   HOWARD HUGHES MED INST,DALLAS,TX 75235.
C3 University of Texas System; University of Texas Southwestern Medical Center; University of Texas Dallas; University of Texas System; University of Texas Dallas; University of Texas Southwestern Medical Center; Howard Hughes Medical Institute
NR 54
TC 538
Z9 630
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 704
EP 711
DI 10.1038/367704a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100048
PM 8107865
DA 2026-03-10
ER

PT J
AU PIERCE, MJ
   WELCH, DL
   MCCLURE, RD
   VANDENBERGH, S
   RACINE, R
   STETSON, PB
AF PIERCE, MJ
   WELCH, DL
   MCCLURE, RD
   VANDENBERGH, S
   RACINE, R
   STETSON, PB
TI THE HUBBLE CONSTANT AND VIRGO CLUSTER DISTANCE FROM OBSERVATIONS OF CEPHEID VARIABLES
SO NATURE
LA English
DT Article
ID france-hawaii telescope; image-stabilization; neutral hydrogen; standard stars; galaxy; scale; supernovae; anisotropy; photometry; flow
AB The distance to the Virgo cluster of galaxies, a primary rung on the ladder to establishing the distance scale of the Universe, 14.9 +/- 1.2 Mpc, has been determined through ground-based observations of Cepheid variables in NGC4571. This agrees very well with other modern distance estimates, and the extragalactic distance scale now seems established. Based on this distance, a Hubble constant of H-0 = 87 +/- 7 km s(-1) Mpc(-1) has been calculated.
C1 KITT PEAK NATL OBSERV,NATL OPT ASTRON OBSERV,TUCSON,AZ 85726.
   MCMASTER UNIV,DEPT PHYS & ASTRON,HAMILTON L8S 4M1,ON,CANADA.
   NATL RES COUNCIL CANADA,HERZBERG INST ASTROPHYS,DOMINION ASTROPHYS OBSERV,VICTORIA V8X 4M6,BC,CANADA.
   UNIV MONTREAL,DEPT PHYS,MONTREAL H3C 3J7,PQ,CANADA.
C3 National Optical Astronomy Observatory; McMaster University; National Research Council Canada; Universite de Montreal
NR 38
TC 212
Z9 219
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 385
EP 389
DI 10.1038/371385a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500032
DA 2026-03-10
ER

PT J
AU ZIMMERMANN, HU
   LEWIN, W
   PREDEHL, P
   ASCHENBACH, B
   FABBIANO, G
   HASINGER, G
   LUBIN, L
   MAGNIER, E
   VANPARADIJS, J
   PETRE, R
   PIETSCH, W
   TRUMPER, J
AF ZIMMERMANN, HU
   LEWIN, W
   PREDEHL, P
   ASCHENBACH, B
   FABBIANO, G
   HASINGER, G
   LUBIN, L
   MAGNIER, E
   VANPARADIJS, J
   PETRE, R
   PIETSCH, W
   TRUMPER, J
TI DETECTION OF SOFT X-RAYS FROM SUPERNOVA 1993J 6 DAYS AFTER OUTBURST
SO NATURE
LA English
DT Article
AB ON 28 March 1993, a new supernova was discovered(1) in the nearby galaxy M81. The proximity of the event (the distance(2) to M81 is only 3.6 Mpc), and the fact that the supernova was detected at an early stage of its outburst(3), makes SN1993J an ideal candidate for the detailed study of the evolution of a supernova in all wavelength regimes. We report here the detection of soft X-ray emissions from SN1993J, six days after the initial discovery, and the subsequent evolution of the X-ray light curve over the next 41 days. The spectral characteristics of the emissions can be readily explained if the X-rays originate in strong shock fronts produced by the rapid expansion of the supernova ejecta into the slow, dense wind of a red supergiant progenitor star(4). The low intrinsic absorption of the earliest emissions requires that any circumstellar material is ionized, probably by the intense radiation of the initial outburst. The decay of the X-ray luminosity with time should provide important constraints on the density profiles of both the circumstellar gas and the outermost layers of the supernova ejecta.
C1 MIT,CTR SPACE RES,CAMBRIDGE,MA 02139.
   HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138.
   PRINCETON UNIV OBSERV,PRINCETON,NJ 08544.
   UNIV AMSTERDAM,ASTRON INST ANTON PANNEKOEK,1098 SJ AMSTERDAM,NETHERLANDS.
   CTR HIGH ENERGY ASTROPHYS,1098 SJ AMSTERDAM,NETHERLANDS.
   GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771.
C3 Massachusetts Institute of Technology (MIT); Harvard University; Smithsonian Institution; Smithsonian Astrophysical Observatory; Princeton University; University of Amsterdam; National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center
RP ZIMMERMANN, HU (corresponding author), MAX PLANCK INST EXTRATERR PHYS,POSTFACH 1603,D-85740 GARCHING,GERMANY.
NR 17
TC 63
Z9 65
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 621
EP 623
DI 10.1038/367621a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800045
DA 2026-03-10
ER

PT J
AU WILLIAMS, JA
   PADDOCK, SW
   VORWERK, K
   CARROLL, SB
AF WILLIAMS, JA
   PADDOCK, SW
   VORWERK, K
   CARROLL, SB
TI ORGANIZATION OF WING FORMATION AND INDUCTION OF A WING-PATTERNING GENE AT THE DORSAL/VENTRAL COMPARTMENT BOUNDARY
SO NATURE
LA English
DT Article
ID drosophila-melanogaster; imaginal disks; differentiation; transcription; encodes; product; elegans; fields
AB The appendages of arthropods and vertebrates possess a third, proximodistal patterning axis that is established after the primary anteroposterior and dorsoventral body axes by mechanisms that are largely unknown. The vestigial gene is required for formation of the entire Drosophila wing, and the dorsal/ventral boundary is shown to organize wing formation and vestigial gene expression. Interactions between dorsal and ventral cells in the growing imaginal disc induce vestigial gene expression through a discrete, extraordinarily conserved imaginal disc-specific enhancer. The link between dorsal/ventral compartmentalization and wing formation distinguishes the development of this sheet-like appendage from that of legs and antennae.
C1 UNIV WISCONSIN, HOWARD HUGHES MED INST, MOLEC BIOL LAB, MADISON, WI 53706 USA.
C3 Howard Hughes Medical Institute; University of Wisconsin System; University of Wisconsin Madison
NR 34
TC 228
Z9 261
U1 0
U2 8
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 299
EP 305
DI 10.1038/368299a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500036
PM 8127364
DA 2026-03-10
ER

PT J
AU MENNERICK, S
   ZORUMSKI, CF
AF MENNERICK, S
   ZORUMSKI, CF
TI GLIAL CONTRIBUTIONS TO EXCITATORY NEUROTRANSMISSION IN CULTURED HIPPOCAMPAL CELLS
SO NATURE
LA English
DT Article
ID electrogenic glutamate uptake; methyl-d-aspartate; time course; receptors; neurons; activation; membrane; currents; channel; patches
AB ALTHOUGH many glial cells possess neurotransmitter receptors and transporters(1-5), little is known about glial participation in neurotransmission. To explore this issue, we recorded neuronal autaptic(6,7) and glial responses from cultured hippocampal single-neuron micro-islands(6,7). Excitatory synaptic events activate rapid electrogenic glial glutamate transporter currents similar to those elicited by exogenous glutamate in other preparations. We show here that glial transporter responses may be used to sense changes in presynaptic efficacy and that glial uptake helps to remove synaptically released glutamate, thereby contributing to the termination of excitatory synaptic currents under certain conditions. These observations provide a framework for understanding the role of glia in both normal and pathological processes.
C1 WASHINGTON UNIV,SCH MED,DEPT ANAT & NEUROBIOL,ST LOUIS,MO 63110.
   WASHINGTON UNIV,SCH MED,PROGRAM NEUROSCI,ST LOUIS,MO 63110.
C3 Washington University (WUSTL); Washington University (WUSTL)
RP MENNERICK, S (corresponding author), WASHINGTON UNIV,SCH MED,DEPT PSYCHIAT,ST LOUIS,MO 63110, USA.
NR 30
TC 301
Z9 330
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 59
EP 62
DI 10.1038/368059a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900052
PM 7906399
DA 2026-03-10
ER

PT J
AU REVENAUGH, J
   SIPKIN, SA
AF REVENAUGH, J
   SIPKIN, SA
TI SEISMIC EVIDENCE FOR SILICATE MELT ATOP THE 410 KM MANTLE DISCONTINUITY
SO NATURE
LA English
DT Article
ID scs reverberations; molten komatiite; crustal growth; differentiation; compression; liquid; models; phase; peridotite; inversion
AB LABORATORY results demonstrating that basic to ultrabasic melts become denser than olivine-rich mantle at pressures above 6 GPa (refs 1-3) have important implications for basalt petrogenesis, mantle differentiation and the storage of volatiles deep in the Earth. A density cross-over between melt and solid in the extensively molten Archaean mantle has been inferred from komatiitic volcanism(4-6) and major-element mass balances?, but present-day evidence of dense melt below the seismic low-velocity zone is lacking. Here we present mantle shear-wave impedance profiles obtained from multiple-ScS reverberation mapping for corridors connecting western Pacific subduction zone earthquakes?with digital seismograph stations in eastern China, imaging a similar to 5.8% impedance decrease roughly 330 km beneath the Sea of Japan, Yellow Sea and easternmost Asia. We propose that this represents the upper surface of a layer of negatively buoyant melt lying on top of the olivine-->beta-phase transition (the 410-km seismic discontinuity). Volatile-rich fluids expelled from the partial melt zone as it freezes may migrate upwards, acting as metasomatic agents(8,9) and perhaps as the deep 'proto-source' of kimberlites(10,11). The remaining, dense, crystalline fraction mould then concentrate above 410 km, producing a garnet-rich layer that may Rush into the transition zone.
C1 US GEOL SURVEY,GOLDEN,CO 80401.
C3 United States Department of the Interior; United States Geological Survey
RP REVENAUGH, J (corresponding author), UNIV CALIF SANTA CRUZ,INST TECTON,SANTA CRUZ,CA 95064, USA.
NR 31
TC 269
Z9 315
U1 0
U2 50
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 474
EP 476
DI 10.1038/369474a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600053
DA 2026-03-10
ER

PT J
AU LANDE, R
   ENGEN, S
   SAETHER, BE
AF LANDE, R
   ENGEN, S
   SAETHER, BE
TI OPTIMAL HARVESTING, ECONOMIC DISCOUNTING AND EXTINCTION RISK IN FLUCTUATING POPULATIONS
SO NATURE
LA English
DT Article
ID natural-populations
AB DETERMINISTIC models demonstrate that when the economic discount rate of future harvests exceeds a critical value related to population growth rate, the strategy that maximizes the present value of cumulative harvest is immediate extinction (liquidation) of the population(1-3). Here we analyse stochastic models to derive optimal strategies that maximize the expected present value of cumulative harvest before extinction of a fluctuating population. Stochastic models reveal that discount rates below the critical value can substantially reduce the mean time to extinction and the expected real harvest before extinction. With an unstable equilibrium at small population size (Allee effect(4-6) or depensation(2)), the critical discount rate is lower in the stochastic model than in the corresponding deterministic model. These results argue against economic discounting in the development of optimal strategies for sustainable use of biological resources.
C1 UNIV TRONDHEIM,AVH,DEPT MATH & STAT,N-7055 DRAGVOLL,NORWAY.
   NORWEGIAN INST NAT RES,N-7004 TRONDHEIM,NORWAY.
C3 Norwegian Institute Nature Research
RP LANDE, R (corresponding author), UNIV OREGON,DEPT BIOL,EUGENE,OR 97403, USA.
NR 23
TC 95
Z9 101
U1 0
U2 28
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 88
EP 90
DI 10.1038/372088a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800077
DA 2026-03-10
ER

PT J
AU DEYOE, EA
   FELLEMAN, DJ
   VANESSEN, DC
   MCCLENDON, E
AF DEYOE, EA
   FELLEMAN, DJ
   VANESSEN, DC
   MCCLENDON, E
TI MULTIPLE PROCESSING STREAMS IN OCCIPITOTEMPORAL VISUAL-CORTEX
SO NATURE
LA English
DT Article
ID macaque monkey; area v2; association cortex; striate cortex; connections; segregation; organization; color; anatomy; form
AB THE earliest stages of cortical visual processing in areas V1 and V2 of the macaque monkey contain internal subdivisions ('blobs' and 'interblobs' in layer 4B in V1; thin, thick and interstripes in V2) that are selectively interconnected and contain neurons with distinctive visual response properties(1-10). Here ae use anatomical pathway tracing to demonstrate that higher visual areas, V4 and the ventral posterior inferotemporal cortex, each contain anatomical subdivisions that have distinct input and output projections. These findings, in conjunction with others(11-15), suggest that modularity and multistream processing within individual cortical areas are widespread features of neocortical organization.
C1 UNIV TEXAS,SCH MED,DEPT NEUROBIOL & ANAT,HOUSTON,TX 77030.
   CALTECH,DIV BIOL 21676,PASADENA,CA 91125.
C3 University of Texas System; California Institute of Technology
RP DEYOE, EA (corresponding author), MED COLL WISCONSIN,DEPT CELLULAR BIOL & ANAT,8701 WATERTOWN PLANK RD,MILWAUKEE,WI 53226, USA.
NR 30
TC 142
Z9 158
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 151
EP 154
DI 10.1038/371151a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100062
PM 8072543
DA 2026-03-10
ER

PT J
AU DARIANSMITH, C
   GILBERT, CD
AF DARIANSMITH, C
   GILBERT, CD
TI AXONAL SPROUTING ACCOMPANIES FUNCTIONAL REORGANIZATION IN ADULT CAT STRIATE CORTEX
SO NATURE
LA English
DT Article
ID massive cortical reorganization; visual-cortex; somatosensory cortex; digit amputation; motor cortex; owl monkeys; spinal-cord; connections; neurons; lesions
AB REMOVAL Of sensory input from a focal region of adult neocortex can lead to a large reorganization of cortical topography within the deprived area during subsequent months(1-9). Although this form of functional recovery is now well documented across several sensory systems, the underlying cellular mechanisms remain elusive. Weeks after binocular retinal lesions silence a corresponding portion of striate cortex in the adult cat, this cortex again becomes responsive, this time to retinal loci immediately outside the scotoma. Earlier findings showed a lack of reorganization in the lateral geniculate nucleus and an inadequate spread of geniculocortical afferents to account for the cortical reorganization, suggesting the involvement of intrinsic cortical connections(4,10). We investigated the possibility that intracortical axonal sprouting mediates long-term reorganization of cortical functional architecture. The anterograde label biocytin was used to compare the density of lateral projections into reorganized and non-deprived cortex. We report here that structural changes in the form of axonal sprouting of long-range laterally projecting neurons accompany topographic remodelling of the visual cortex.
C1 ROCKEFELLER UNIV,NEW YORK,NY 10021.
C3 Rockefeller University
NR 32
TC 506
Z9 545
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 737
EP 740
DI 10.1038/368737a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300057
PM 8152484
DA 2026-03-10
ER

PT J
AU LEE, JC
   LAYDON, JT
   MCDONNELL, PC
   GALLAGHER, TF
   KUMAR, S
   GREEN, D
   MCNULTY, D
   BLUMENTHAL, MJ
   HEYS, JR
   LANDVATTER, SW
   STRICKLER, JE
   MCLAUGHLIN, MM
   SIEMENS, IR
   FISHER, SM
   LIVI, GP
   WHITE, JR
   ADAMS, JL
   YOUNG, PR
AF LEE, JC
   LAYDON, JT
   MCDONNELL, PC
   GALLAGHER, TF
   KUMAR, S
   GREEN, D
   MCNULTY, D
   BLUMENTHAL, MJ
   HEYS, JR
   LANDVATTER, SW
   STRICKLER, JE
   MCLAUGHLIN, MM
   SIEMENS, IR
   FISHER, SM
   LIVI, GP
   WHITE, JR
   ADAMS, JL
   YOUNG, PR
TI A PROTEIN-KINASE INVOLVED IN THE REGULATION OF INFLAMMATORY CYTOKINE BIOSYNTHESIS
SO NATURE
LA English
DT Article
ID tumor-necrosis-factor; rna-binding protein; tyrosine phosphorylation; murine macrophages; endotoxin; il-1; lipopolysaccharide; interleukin-1; purification; expression
AB Production of interleukin-1 and tumour necrosis factor from stimulated human monocytes is inhibited by a new series of pyridinyl-imidazole compounds. Using radiolabelled and radio-photoaffinity-labelled chemical probes, the target of these compounds was identified as a pair of closely related mitogen-activated protein kinase homologues, termed CSBPs. Binding of the pyridinyl-imidazole compounds inhibited CSBP kinase activity and could be directly correlated with their ability to inhibit cytokine production, suggesting that the CSBPs are critical for cytokine production.
C1 SMITHKLINE BEECHAM PHARMACEUT,DEPT MOLEC IMMUNOL,KING OF PRUSSIA,PA 19406.
   SMITHKLINE BEECHAM PHARMACEUT,DEPT MED CHEM,KING OF PRUSSIA,PA 19406.
   SMITHKLINE BEECHAM PHARMACEUT,DEPT RADIOCHEM,KING OF PRUSSIA,PA 19406.
   SMITHKLINE BEECHAM PHARMACEUT,DEPT PROT BIOCHEM,KING OF PRUSSIA,PA 19406.
   SMITHKLINE BEECHAM PHARMACEUT,DEPT GENE EXPRESS SCI,KING OF PRUSSIA,PA 19406.
C3 GlaxoSmithKline; Glaxosmithkline USA; GlaxoSmithKline; Glaxosmithkline USA; GlaxoSmithKline; Glaxosmithkline USA; GlaxoSmithKline; Glaxosmithkline USA; GlaxoSmithKline; Glaxosmithkline USA
RP LEE, JC (corresponding author), SMITHKLINE BEECHAM PHARMACEUT,DEPT CELLULAR BIOCHEM,KING OF PRUSSIA,PA 19406, USA.
NR 44
TC 3138
Z9 3447
U1 0
U2 135
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 739
EP 746
DI 10.1038/372739a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200042
PM 7997261
DA 2026-03-10
ER

PT J
AU HUMPHREYS, GW
   ROMANI, C
   OLSON, A
   RIDDOCH, MJ
   DUNCAN, J
AF HUMPHREYS, GW
   ROMANI, C
   OLSON, A
   RIDDOCH, MJ
   DUNCAN, J
TI NON SPATIAL EXTINCTION FOLLOWING LESIONS OF THE PARIETAL LOBE IN HUMANS
SO NATURE
LA English
DT Article
ID attention; pictures; object; words
AB EFFICIENT behaviour in the visual environment requires selection between stimuli competing for control of action. Many current models of selection are spatial: relevant objects are chosen by attending to their locations(1-3). The unilateral stimulus extinction observed following lesions of the parietal lobe provides evidence for spatial selection(4). Such patients may identify a single stimulus presented in their contralesional field, but can fail to detect the same stimulus when a competing stimulus is shown simultaneously on the ipsilesional side(5). Here we demonstrate that extinction need not be spatial in nature, but may be determined by characteristics of the objects to be selected. In two patients with parietal lobe lesions and poor spatial localization, pictures extinguished words and closed shapes extinguished open shapes. This object-based extinction indicates the existence of biases within non-spatial selection mechanisms which are independent of biases produced by spatial selection mechanisms. We suggest that selection of objects for action requires that the 'winners' produced by the independent competitive biases for selection are bound together within distinct neural areas concerned with object properties and space.
C1 MRC,APPL PSYCHOL UNIT,CAMBRIDGE CB2 2EF,ENGLAND.
C3 University of Cambridge
RP HUMPHREYS, GW (corresponding author), UNIV BIRMINGHAM,SCH PSYCHOL,COGNIT SCI RES CTR,BIRMINGHAM B15 2TT,W MIDLANDS,ENGLAND.
NR 16
TC 102
Z9 104
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 357
EP 359
DI 10.1038/372357a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700054
PM 7969493
DA 2026-03-10
ER

PT J
AU ELSTON, R
   THOMPSON, KL
   HILL, GJ
AF ELSTON, R
   THOMPSON, KL
   HILL, GJ
TI DETECTION OF STRONG IRON EMISSION FROM QUASARS AT REDSHIFT-Z-GREATER-THAN-3
SO NATURE
LA English
DT Article
ID fe-ii emission; active galactic nuclei; x-ray property; seyfert-1 galaxy; iras quasar; qsos; redshift; spectra; spectrophotometry; supernovae
AB QUASARs are distant, luminous objects generally thought to be powered by the accretion of gas onto a supermassive black hole , their spectra are characterized by broad emission lines originating from a dense region close to the central energy source1. The best-studied spectral region in low-redshift quasars is near the Hbeta line at 4,861 angstrom (in the quasar rest frame) where there are also lines arising from singly ionized iron and doubly ionized oxygen. New technology has enabled us to detect strong iron emission in the spectra of the high-redshift (z > 3) quasars Q0014 + 813 and Q0663 + 680, in which these lines are redshifted to the near-infrared. The strength of this emission suggests an iron abundance (relative to hydrogen) higher than in the solar neighbourhood. This high iron abundance supports the view that quasars are located in the centres of massive galaxies. If type la supernovae are responsible for the iron enrichment2, significant star formation must have taken place in the host galaxies at least one billion years earlier, providing a constraint on the age of the Universe at that redshift.
C1 USN,RES LAB,WASHINGTON,DC 20375.
   UNIV TEXAS,MCDONALD OBSERV,AUSTIN,TX 78712.
C3 United States Department of Defense; United States Navy; United States Naval Research Laboratory; NRL Chesapeake; University of Texas System; University of Texas Austin
RP ELSTON, R (corresponding author), CERRO TOLOLO INTERAMER OBSERV,CASILLA 603,LA SERENA,CHILE.
NR 33
TC 42
Z9 43
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 250
EP 251
DI 10.1038/367250a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400047
DA 2026-03-10
ER

PT J
AU NOURSE, J
   FIRPO, E
   FLANAGAN, WM
   COATS, S
   POLYAK, K
   LEE, MH
   MASSAGUE, J
   CRABTREE, GR
   ROBERTS, JM
AF NOURSE, J
   FIRPO, E
   FLANAGAN, WM
   COATS, S
   POLYAK, K
   LEE, MH
   MASSAGUE, J
   CRABTREE, GR
   ROBERTS, JM
TI INTERLEUKIN-2-MEDIATED ELIMINATION OF THE P27(KIP1) CYCLIN-DEPENDENT KINASE INHIBITOR PREVENTED BY RAPAMYCIN
SO NATURE
LA English
DT Article
ID catalytic subunit; protein-kinase; cdk2 activity; phosphorylation; fibroblasts; lymphocytes; activation; p40(mo15); p34(cdc2); fk506
AB THE cyclin-dependent kinase (Cdk) enzymes, when associated with the G1 cycIins D and E, are rate-limiting for entry into the S phase of the cell cycle(1,2). During T-cell mitogenesis, antigen-receptor signalling promotes synthesis of cyclin E and its catalytic partner, Cdk2, and interleukin-2 (IL-2) signalling activates cyclin E/Cdk2 complexes(3). Rapamycin is a potent immunosuppressant which specifically inhibits G1-to-S-phase progression, leading to cell-cycle arrest in yeast and mammals(4-7) Here we report that IL-2 allows Cdk activation by causing the elimination of the Cdk inhibitor protein p27(Kip1), and that this is prevented by rapamycin. By contrast, the Cdk inhibitor p21 is induced by IL-2 and this induction is blocked by rapamycin. Our results show that p27(Kip1) governs Cdk activity during the transition from quiescence to S phase in T lymphocytes and that p21 function may be restricted to cycling cells.
C1 STANFORD UNIV,SCH MED,HOWARD HUGHES MED INST,STANFORD,CA 94305.
   FRED HUTCHINSON CANC RES CTR,DEPT BASIC SCI,SEATTLE,WA 98104.
   MEM SLOAN KETTERING CANC CTR,CELL BIOL & GENET PROGRAM,NEW YORK,NY 10021.
C3 Howard Hughes Medical Institute; Stanford University; Fred Hutchinson Cancer Center; Memorial Sloan Kettering Cancer Center
RP NOURSE, J (corresponding author), STANFORD UNIV,SCH MED,PROGRAM CANC BIOL,STANFORD,CA 94305, USA.
NR 24
TC 907
Z9 978
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 570
EP 573
DI 10.1038/372570a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200058
PM 7990932
DA 2026-03-10
ER

PT J
AU XU, Z
   XIAO, FS
   PURNELL, SK
   ALEXEEV, O
   KAWI, S
   DEUTSCH, SE
   GATES, BC
AF XU, Z
   XIAO, FS
   PURNELL, SK
   ALEXEEV, O
   KAWI, S
   DEUTSCH, SE
   GATES, BC
TI SIZE-DEPENDENT CATALYTIC ACTIVITY OF SUPPORTED METAL-CLUSTERS
SO NATURE
LA English
DT Article
ID hydrogen chemisorption; gas-phase; zeolite
AB BECAUSE catalysis by metals is a surface phenomenon, many technological catalysts contain small (typically nanometre-sized) supported metal particles with a large fraction of the atoms exposed(1). Many reactions, such as hydrocarbon hydrogenations, are structure-insensitive, proceeding at approximately the same rate on metal particles of various sizes provided that they are larger than about 1 nm and show bulk-like metallic behaviour(1). But it is not known whether the catalytic properties of metal particles become size-dependent as the particles become so small that they are no longer metallic in character. Here we investigate the catalytic behaviour of precisely defined clusters of just four and six iridium atoms on solid supports. We find that the Ir-4 and Ir-6 clusters differ in catalytic activity both from each other and from metallic Ir particles. This raises the possibility of tailoring the catalytic behaviour of metal clusters by controlling the cluster size.
C1 UNIV CALIF DAVIS, DEPT CHEM ENGN & MAT SCI, DAVIS, CA 95616 USA.
C3 University of California System; University of California Davis
NR 17
TC 355
Z9 386
U1 3
U2 172
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 346
EP 348
DI 10.1038/372346a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700049
DA 2026-03-10
ER

PT J
AU CRAIG, AD
   BUSHNELL, MC
   ZHANG, ET
   BLOMQVIST, A
AF CRAIG, AD
   BUSHNELL, MC
   ZHANG, ET
   BLOMQVIST, A
TI A THALAMIC NUCLEUS SPECIFIC FOR PAIN AND TEMPERATURE SENSATION
SO NATURE
LA English
DT Article
ID neurons; area; cat; stimuli; monkey; tract
AB THE existence of a posterolateral thalamic relay nucleus for pain and temperature sensation was postulated in 1911, on the basis of the stroke-induced analgesia and thermanaesthesia found paradoxically in patients with thalamic pain syndrome(1). Pain or temperature sensations can be evoked in humans by electrical stimulation in a vaguely defined region of the posterolateral thalamus(2,3). Here we use anterograde tracing and single unit recordings to demonstrate that there is a distinct nucleus in the posterior thalamus of the macaque monkey that receives a dense, topographic input from spinothalamic lamina I neurons and in which almost all neurons are nociceptive- or thermoreceptive-specific. Immunohistochemical staining showed that this nucleus is defined by a dense calbindin-positive fibre plexus in the macaque, so we applied the same staining method to sections of human thalamus. We found a nearly identical fibre plexus localized within a distinct nucleus that is cytoarchitectonically homologous to the lamina I relay nucleus in the macaque thalamus. The stereotaxic coordinates of this nucleus and its location relative to the main somatosensory representation fit clinical descriptions of the pain-producing region in humans. We conclude that this is a specific thalamic nucleus for pain and temperature sensation in both monkey and human.
C1 UNIV MONTREAL,FAC MED DENT,DEPT STOMATOL,MONTREAL H3C 3J7,PQ,CANADA.
   UNIV MONTREAL,FAC MED DENT,CTR RECH SCI NEUROL,MONTREAL H3C 3J7,PQ,CANADA.
   LINKOPING UNIV,FAC HLTH SCI,DEPT CELL BIOL,S-58185 LINKOPING,SWEDEN.
C3 Universite de Montreal; Universite de Montreal; Linkoping University
RP CRAIG, AD (corresponding author), BARROW NEUROL INST,DIV NEUROBIOL,350 W THOMAS RD,PHOENIX,AZ 85013, USA.
NR 28
TC 457
Z9 519
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 770
EP 773
DI 10.1038/372770a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200050
PM 7695716
DA 2026-03-10
ER

PT J
AU SHENG, M
   CUMMINGS, J
   ROLDAN, LA
   JAN, YN
   JAN, LY
AF SHENG, M
   CUMMINGS, J
   ROLDAN, LA
   JAN, YN
   JAN, LY
TI CHANGING SUBUNIT COMPOSITION OF HETEROMERIC NMDA RECEPTORS DURING DEVELOPMENT OF RAT CORTEX
SO NATURE
LA English
DT Article
ID visual-cortex; channel; currents; cloning; neurons; brain
AB ACTIVATION Of the N-methyl-D-aspartate (NMDA) receptor is important for certain forms of activity-dependent synaptic plasticity, such as long-term potentiation (reviewed in ref. 1), and the patterning of connections during development of the visual system (reviewed in refs 2, 3). Several subunits of the NMDA receptor have been cloned: these are NMDAR1 (NR1), and NMDAR2A, 2B, 2C and 2D (NR2A-D)(4-8). Based on heterologous co-expression studies, it is inferred that NR1 encodes an essential subunit of NMDA receptors and that functional diversity of NMDA receptors in vivo is effected by differential incorporation of subunits NR2A-NR2D(5-8). Little is known, however, about the actual subunit composition or heterogeneity of NMDA receptors in the brain. By co-immunoprecipitation with subunit-specific antibodies, we present here direct evidence that NMDA receptors exist in rat neocortex as heteromeric complexes of considerable heterogeneity, some containing both NR2A and NR2B subunits. A progressive alteration in subunit composition seen postnatally could contribute to NMDA-receptor variation and changing synaptic plasticity during cortical development.
C1 UNIV CALIF SAN FRANCISCO,DEPT PHYSIOL,SAN FRANCISCO,CA 94143.
   UNIV CALIF SAN FRANCISCO,DEPT BIOCHEM,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco; University of California System; University of California San Francisco
RP SHENG, M (corresponding author), UNIV CALIF SAN FRANCISCO,HOWARD HUGHES MED INST,SAN FRANCISCO,CA 94143, USA.
NR 28
TC 1168
Z9 1351
U1 0
U2 52
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 144
EP 147
DI 10.1038/368144a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000065
PM 8139656
DA 2026-03-10
ER

PT J
AU CIAPA, B
   PESANDO, D
   WILDING, M
   WHITAKER, M
AF CIAPA, B
   PESANDO, D
   WILDING, M
   WHITAKER, M
TI CELL-CYCLE CALCIUM TRANSIENTS DRIVEN BY CYCLIC CHANGES IN INOSITOL TRISPHOSPHATE LEVELS
SO NATURE
LA English
DT Article
ID nuclear-envelope breakdown; intracellular free calcium; sea-urchin embryos; translational control; eggs; fertilization; anaphase; ca2+
AB TRANSIENT changes in intracellular calcium ([Ca2+](i)) have been shown to punctuate the cell cycle in various types of cells in culture(1-5) and in early embryos(6-12). The [Ca2+](i) transients are correlated with cell-cycle events: pronuclear migration, nuclear envelope breakdown, the metaphase-anaphase transition of mitosis, and cytokinesis. Mitotic events fan be induced by injecting calcium and prevented by injecting calcium chelators into the sea urchin embryo(10,13). Cell-cycle calcium transients differ from the transients linked to membrane signal transduction pathways: they are generated by an endogenous mechanism, not by plasma membrane receptor complexes, and their trigger is unknown. We report here that the phosphoinositide messenger system oscillates during the early embryonic cell cycle in the sea urchin, leading to cyclic increases in inositol trisphosphate that trigger cell-cycle [Ca2+](i) transients and mitosis by calcium release from intracellular stores.
C1 FAC SCI NICE,PHYSIOL CELLULAIRE & COMPAREE LAB,F-06108 NICE,FRANCE.
   INSERM,U303,F-06230 VILLEFRANCHE MER,FRANCE.
   UNIV LONDON UNIV COLL,DEPT PHYSIOL,LONDON WC1E 6BT,ENGLAND.
C3 Universite Cote d'Azur; Institut National de la Sante et de la Recherche Medicale (Inserm); University of London; University College London
FU Wellcome Trust Funding Source: Medline
NR 28
TC 167
Z9 178
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 875
EP 878
DI 10.1038/368875a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700077
PM 8159248
DA 2026-03-10
ER

PT J
AU ARENAS, E
   PERSSON, H
AF ARENAS, E
   PERSSON, H
TI NEUROTROPHIN-3 PREVENTS THE DEATH OF ADULT CENTRAL NORADRENERGIC NEURONS IN-VIVO
SO NATURE
LA English
DT Article
ID nerve growth-factor; cholinergic neurons; locus-ceruleus; messenger-rna; factor family; rat-brain; molecular-cloning; cell-death; trk family; expression
AB NEUROTROPHIN-3 (NT-3)1-4 and neurotrophin-4/5 (NT4)5-7, together with nerve growth factor and brain-derived neurotrophic factor, are members of the neurotrophin family of proteins8,9 which supports the survival of vertebrate neurons. However, no function in vivo has been described for NT4 and limited information is available on the role of the other neurotrophins in the central nervous system in vivo. Nerve growth factor prevents the degeneration of lesioned septal cholinergic neurons in the adult brain10-13, whereas brain-derived neurotrophic factor prevents the death of developing motor neurons14-16 and a subpopulation of adult septal cholinergic neurons17. Finally, NT-3 partially prevents the death of facial motor neurons in newborn rats16. To assess the role of NT-3 and NT4 in the adult brain in vivo, we implanted genetically modified fibroblasts that constitutively express high levels of NT-3 or NT-4. The results show that NT-3, but no other neurotrophin, prevents the degeneration of noradrenergic neurons of the locus coeruleus in a 6-hydroxydopamine lesion model that resembles the pattern of cell loss found in Alzheimer's disease18,19. These results imply that NT-3 may have therapeutic potential for preventing the death of noradrenergic neurons in the locus coeruleus.
RP ARENAS, E (corresponding author), KAROLINSKA INST,DEPT MED BIOCHEM & BIOPHYS,MOLEC NEUROBIOL LAB,S-17177 STOCKHOLM,SWEDEN.
NR 33
TC 197
Z9 215
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 368
EP 371
DI 10.1038/367368a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000067
PM 8114936
DA 2026-03-10
ER

PT J
AU SALI, A
   SHAKHNOVICH, E
   KARPLUS, M
AF SALI, A
   SHAKHNOVICH, E
   KARPLUS, M
TI HOW DOES A PROTEIN FOLD
SO NATURE
LA English
DT Article
ID globular-proteins; dynamics
AB THE number of all possible conformations of a polypeptide chain is too large to be sampled exhaustively. Nevertheless, protein sequences do fold into unique native states in seconds (the Levinthal paradox). To determine how the Levinthal parades is resolved, we use a lattice Monte Carlo model in which the global minimum (native state) is known. The necessary and sufficient condition for folding in this model is that the native state be a pronounced global minimum on the potential surface. This guarantees thermodynamic stability of the native state at a temperature where the chain does not get trapped in local minima. Folding starts by a rapid collapse from a random-coil state to a random semi-compact globule. It then proceeds by a slow, rate-determining search through the semicompact states to find a transition state from which the chain folds rapidly to the native state. The elements of the folding mechanism that lead to the resolution of the Levinthal parades are the reduced number of conformations that need to be searched in the semicompact globule (similar to 10(10) versus similar to 10(16) for the random coil) and the existence of many (similar to 10(3)) transition states. The results have evolutionary implications and suggest principles for the folding of real proteins.
C1 HARVARD UNIV,DEPT CHEM,CAMBRIDGE,MA 02138.
C3 Harvard University
NR 22
TC 886
Z9 969
U1 0
U2 117
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 248
EP 251
DI 10.1038/369248a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700061
PM 7710478
DA 2026-03-10
ER

PT J
AU YAN, MH
   DAI, TN
   DEAK, JC
   KYRIAKIS, JM
   ZON, LI
   WOODGETT, JR
   TEMPLETON, DJ
AF YAN, MH
   DAI, TN
   DEAK, JC
   KYRIAKIS, JM
   ZON, LI
   WOODGETT, JR
   TEMPLETON, DJ
TI ACTIVATION OF STRESS-ACTIVATED PROTEIN-KINASE BY MEKK1 PHOSPHORYLATION OF ITS ACTIVATOR SEK1
SO NATURE
LA English
DT Article
ID raf; tyrosine
AB A KINASE distinct from the MEK activator Raf(1-3), termed MEK kinase-1 (MEKK), was originally identified by virtue of its homology to kinases involved in yeast mating signal cascades(4). Like Raf, MEKK is capable of activating MEK in vitro(4,5). High-level expression of MEKK in COS-7 cells(4) or using vaccinia virus vectors(5) also activates MEK and MAPK, indicating that MEKK and Raf provide alternative means of activating the MAPK signalling pathmay. We have derived NIH3T3 cell sublines that can be induced to express active MEKK. Here we show that induction of MEKK does not result in the activation of MAPK, but instead stimulates the stress-activated protein kinases (SAPKs)(6-8) which are identical to a Jun amino-terminal kinase(9,10). We find that MEKK regulates a new signalling cascade by phosphorylating an SAPK activator, SEK1 which in turn phosphorylates and activates SAPK.
C1 CASE WESTERN RESERVE UNIV HOSP, SCH MED, CELL BIOL PROGRAM, CLEVELAND, OH 44106 USA.
   PRINCESS MARGARET HOSP, ONTARIO CANC INST, TORONTO M4X 1K9, ON, CANADA.
   MASSACHUSETTS GEN HOSP E, MED SERV, DIABET RES LAB, BOSTON, MA 02129 USA.
   HARVARD UNIV, MASSACHUSETTS GEN HOSP EAST, DEPT MED, BOSTON, MA 02129 USA.
   HARVARD UNIV, CHILDRENS HOSP,SCH MED,HOWARD HUGHES MED INST, DIV HEMATOL, BOSTON, MA 02115 USA.
C3 University System of Ohio; Case Western Reserve University; Case Western Reserve University Hospital; University of Toronto; University Health Network Toronto; Princess Margaret Cancer Centre; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Howard Hughes Medical Institute; Harvard University; Harvard University Medical Affiliates; Boston Children's Hospital; Harvard Medical School
RP YAN, MH (corresponding author), CASE WESTERN RESERVE UNIV HOSP, SCH MED, INST PATHOL, 10900 E EUCLID AVE, CLEVELAND, OH 44106 USA.
NR 20
TC 715
Z9 763
U1 0
U2 10
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 798
EP 800
DI 
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200058
PM 7997270
DA 2026-03-10
ER

PT J
AU COLE, DR
   MONGER, HC
AF COLE, DR
   MONGER, HC
TI INFLUENCE OF ATMOSPHERIC CO2 ON THE DECLINE OF C4 PLANTS DURING THE LAST DEGLACIATION
SO NATURE
LA English
DT Article
ID isotopic composition; ice core; paleoclimatic significance; north-america; carbon; record; paleosols; climate
AB CHANGES in atmospheric carbon dioxide concentrations in the past may have caused changes in vegetation type1,2, and it has been suggested2 that the isotopic signature of such vegetation shifts, preserved in palaeosols3, might be used as a proxy for past CO2 variations. But the connection between palaeosol isotopic signatures and atmospheric CO2 concentrations has been difficult to establish, partly because of the unreliability of CO2 proxies and partly because of the difficulty in ruling out other potential causes of vegetation changes, such as climate4. Here we present palaeosol carbon isotope ratios that reveal a shift from C4-dominated grasses to C3-dominated shrubs about 7-9 kyr ago on an alluvial fan system in the Chihuahuan desert, New Mexico. This coincides with a rapid increase in atmospheric CO2 concentration recorded in Antarctic ice cores5-8 and increased aridity recorded by geomorphic reconstructions9-11 and packrat remains12. Palaeosol oxy gen isotope ratios, which depend on temperature and moisture, were relatively constant during the vegetation shift, suggesting that the CO2 change, rather than climate, was the dominant cause. We conclude that the carbon isotope ratios of ancient soils can indeed be used as a proxy for past CO2 changes.
C1 NEW MEXICO STATE UNIV, DEPT AGRON & HORT, LAS CRUCES, NM 88003 USA.
C3 New Mexico State University
RP COLE, DR (corresponding author), OAK RIDGE NATL LAB, DIV CHEM & ANALYT SCI, OAK RIDGE, TN 37831 USA.
NR 34
TC 90
Z9 94
U1 0
U2 10
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 533
EP 536
DI 10.1038/368533a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500050
DA 2026-03-10
ER

PT J
AU LI, MY
   ACERO, AA
   HUANG, ZQ
   RICE, SA
AF LI, MY
   ACERO, AA
   HUANG, ZQ
   RICE, SA
TI FORMATION OF AN ORDERED LANGMUIR MONOLAYER BY A NONPOLAR CHAIN MOLECULE
SO NATURE
LA English
DT Article
ID perfluoro-n-eicosane; air-water-interface; phase-transitions; dynamics
AB AMPHIPHILIC molecules, which contain a polar 'head' group and a hydrophobic 'tail', will generally form monolayers at the air-water interface in which the molecules protrude from the interface with the tails in the air. These 'Langmuir monolayers' exhibit a variety of phases as a function of surface pressure and temperature, including an ordered, two-dimensional crystalline phase1-3. It might be considered that the amphiphilic nature of the molecules allows this oriented, tail up arrangement and the consequent formation of a well ordered phase. Here, by contrast, we report that the nonpolar molecule perfluoro-n-eicosane (F(CF2)20F) will form stable, ordered Langmuir monolayers on water, even though they have no amphiphilic character. Grazing-incidence X-ray diffraction studies of these monolayers show that the molecules are vertically aligned and are packed in a hexagonal array over a range of temperature. We suggest that van der Waals forces alone are sufficient to stabilize the monolayer in this case.
C1 UNIV CHICAGO,JAMES FRANCK INST,CHICAGO,IL 60637.
C3 University of Chicago
RP LI, MY (corresponding author), UNIV CHICAGO,DEPT CHEM,CHICAGO,IL 60637, USA.
NR 10
TC 107
Z9 110
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 151
EP 153
DI 10.1038/367151a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000053
DA 2026-03-10
ER

PT J
AU ZANARIA, E
   MUSCATELLI, F
   BARDONI, B
   STROM, TM
   GUIOLI, S
   GUO, WW
   LALLI, E
   MOSER, C
   WALKER, AP
   MCCABE, ERB
   MEITINGER, T
   MONACO, AP
   SASSONECORSI, P
   CAMERINO, G
AF ZANARIA, E
   MUSCATELLI, F
   BARDONI, B
   STROM, TM
   GUIOLI, S
   GUO, WW
   LALLI, E
   MOSER, C
   WALKER, AP
   MCCABE, ERB
   MEITINGER, T
   MONACO, AP
   SASSONECORSI, P
   CAMERINO, G
TI AN UNUSUAL MEMBER OF THE NUCLEAR HORMONE-RECEPTOR SUPERFAMILY RESPONSIBLE FOR X-LINKED ADRENAL HYPOPLASIA CONGENITA
SO NATURE
LA English
DT Article
ID coup transcription factor; dna-binding domains; retinoic acid; gene superfamily; glycerol kinase; genomic organization; expression; cloning; protein; xp21
AB X-linked adrenal hypoplasia congenita is a developmental disorder of the human adrenal gland that results in profound hormonal deficiencies and is,lethal if untreated. We have isolated the gene responsible for the disease, DAX-1, which is deleted or mutated in X-linked adrenal hypoplasia patients. DAX-1 encodes a new member of the nuclear hormone receptor superfamily displaying a novel DNA-binding domain. The DAX-1 product acts as a dominant negative regulator of transcription mediated by the retinoic acid receptor.
C1 UNIV PAVIA,I-27100 PAVIA,ITALY.
   JOHN RADCLIFFE HOSP,INST MOLEC MED,IMPERIAL CANC RES FUND LABS,OXFORD OX3 9DU,ENGLAND.
   LMU,KINDERPOLIKLIN,PADIAT GENET ABT,D-80336 MUNICH,GERMANY.
   BAYLOR COLL MED,DEPT PEDIAT,HOUSTON,TX 77030.
   BAYLOR COLL MED,DEPT MOLEC & HUMAN GENET,HOUSTON,TX 77030.
   ULP,CNRS,INSERM,INST GENET & BIOL MOLEC CELLULAIRE,IGBMC,F-67404 ILLKIRCH GRAFFENS,FRANCE.
   UNIV SASSARI,IST ISTOL & EMBRIOL,I-07100 SASSARI,ITALY.
C3 University of Pavia; University of Oxford; Cancer Research UK; University of Munich; Baylor College of Medicine; Baylor College of Medicine; Institut National de la Sante et de la Recherche Medicale (Inserm); Centre National de la Recherche Scientifique (CNRS); University of Sassari
FU Telethon [B.05] Funding Source: Medline
NR 45
TC 706
Z9 778
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 635
EP 641
DI 10.1038/372635a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700075
PM 7990953
DA 2026-03-10
ER

PT J
AU WOLDEGABRIEL, G
   WHITE, TD
   SUWA, G
   RENNE, P
   DEHEINZELIN, J
   HART, WK
   HEIKEN, G
AF WOLDEGABRIEL, G
   WHITE, TD
   SUWA, G
   RENNE, P
   DEHEINZELIN, J
   HART, WK
   HEIKEN, G
TI ECOLOGICAL AND TEMPORAL PLACEMENT OF EARLY PLIOCENE HOMINIDS AT ARAMIS, ETHIOPIA
SO NATURE
LA English
DT Article
ID middle-awash-valley; stratigraphy; discovery; hadar; afar
AB SEDIMENTARY deposits in the Middle Awash research area of Ethiopia's Afar depression have yielded vertebrate fossils including the most ancient hominids known. Radioisotopic dating, geochemical analysis of interbedded volcanic ashes and biochronological considerations place the hominid-bearing deposits at around 4.4 million years of age. Sedimentological, botanical and faunal evidence suggests a wooded habitat for the Aramis hominids.
C1 UNIV CALIF BERKELEY,HUMAN EVOLUTIONARY STUDIES LAB,BERKELEY,CA 94720.
   LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545.
   UNIV TOKYO,DEPT ANTHROPOL,BUNKYO KU,TOKYO 113,JAPAN.
   BERKELEY GEOCHRONOL CTR,BERKELEY,CA 94709.
   INST ROYAL SCI NAT BELGIQUE,B-1040 BRUSSELS,BELGIUM.
   MIAMI UNIV,DEPT GEOL,OXFORD,OH 45056.
C3 University of California System; University of California Berkeley; United States Department of Energy (DOE); Los Alamos National Laboratory; University of Tokyo; Berkeley Geochronolgy Center; University System of Ohio; Miami University
NR 17
TC 211
Z9 235
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 330
EP 333
DI 10.1038/371330a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400051
PM 8090201
DA 2026-03-10
ER

PT J
AU NICOLAS, A
   BOUDIER, F
   ILDEFONSE, B
AF NICOLAS, A
   BOUDIER, F
   ILDEFONSE, B
TI EVIDENCE FROM THE OMAN OPHIOLITE FOR ACTIVE MANTLE UPWELLING BENEATH A FAST-SPREADING RIDGE
SO NATURE
LA English
DT Article
ID mid-atlantic ridge; east pacific rise; gravity-anomaly; plate boundary; rate dependence; ocean ridges; centers; flow; accretion; gabbros
AB IT is commonly accepted that as oceanic lithosphere cools, it slides away from the spreading centre under its om weight(1). It has been suggested(2-5) that even at the spreading axis this process controls the dynamics, causing asthenospheric mantle material to rise passively before being dragged away from the ridge by the overlying lithosphere. Alternatively, the upwelling of the asthenosphere at the ridge might be 'active', caused by the buoyancy of partial melt(6-10) or of the less dense peridotite left behind by such melting(11,12). At slow-spreading ridges, 'bull's-eye' gravity anomalies(13,14) have been interpreted as suggesting focused accretion, and hence active mantle diapirs. At fast-spreading ridges, however, these anomalies are weaker and less clearly three-dimensional(15), which may reflect passive mantle upwelling(16). Here we show that structural data from the Oman ophiolite, which is thought to have been created at a fast-spreading ridge(17,18) are consistent with active mantle upwelling beneath the ridge, and not with models of passive flow. The absence of well marked bull's-eye anomalies at fast spreading ridges may be explained by their relatively constant crustal thickness and near-isostatic equilibrium.
RP NICOLAS, A (corresponding author), UNIV MONTPELLIER 2,CNRS,TECTONOPHYS LAB,F-34095 MONTPELLIER 05,FRANCE.
NR 31
TC 65
Z9 70
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 51
EP 53
DI 10.1038/370051a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100055
DA 2026-03-10
ER

PT J
AU SIMONICH, SL
   HITES, RA
AF SIMONICH, SL
   HITES, RA
TI IMPORTANCE OF VEGETATION IN REMOVING POLYCYCLIC AROMATIC-HYDROCARBONS FROM THE ATMOSPHERE
SO NATURE
LA English
DT Article
ID deposition; fluxes; degradation; forest; ozone; pahs
AB ANTHROPOGENIC semi-volatile organic compounds such as polycyclic aromatic hydrocarbons (PAHs) are highly lipophilic (which makes them likely to accumulate in animal tissue), and some are carcinogenic or mutagenic(1). Although such compounds are known to accumulate in vegetation(2-5), little is known about the quantitative role played by vegetation in removing them from the atmosphere. We have developed a mass-balance model for PAHs for the northeast of the United States, based on measurements of PAHs in soil and vegetation from Bloomington, Indiana, and published values for PAH concentrations and fluxes in air, water, sediments and soils. Our model shows that 44 +/- 18% of the PAHs emitted into the atmosphere from sources in this region are removed by vegetation. Although the equilibrium between the atmosphere and vegetation depends on ambient temperature(6), we believe that most of the PAHs absorbed by vegetation at the end of the growing season are incorporated into the soil(7,8) and permanently removed from the atmosphere.
C1 INDIANA UNIV,SCH PUBL & ENVIRONM AFFAIRS,BLOOMINGTON,IN 47405.
   INDIANA UNIV,DEPT CHEM,BLOOMINGTON,IN 47405.
C3 Indiana University System; Indiana University Bloomington; Indiana University System; Indiana University Bloomington
NR 26
TC 266
Z9 322
U1 2
U2 161
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 49
EP 51
DI 10.1038/370049a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100054
DA 2026-03-10
ER

PT J
AU BARBER, J
   ANDERSSON, B
AF BARBER, J
   ANDERSSON, B
TI REVEALING THE BLUEPRINT OF PHOTOSYNTHESIS
SO NATURE
LA English
DT Article
ID ii reaction center; cyanobacterium mastigocladus-laminosus; electron-transfer; photosystem-ii; rhodobacter-sphaeroides; 3-dimensional structure; membrane-protein; rhodopseudomonas-viridis; biological molecules; manganese cluster
AB Recent research has revealed the nature of the reactions that underlie the conversion of solar energy into chemical energy by photosynthesis. Armed with this knowledge, a blueprint for new technologies to exploit solar energy is emerging.
C1 UNIV STOCKHOLM,ARRHENIUS LABS,DEPT BIOCHEM,S-10691 STOCKHOLM,SWEDEN.
C3 Stockholm University
RP BARBER, J (corresponding author), UNIV LONDON IMPERIAL COLL SCI & TECHNOL,DEPT BIOCHEM,WOLFSON LABS,PHOTOSYNTH RES GRP,LONDON SW7 2AY,ENGLAND.
NR 52
TC 269
Z9 292
U1 0
U2 62
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 31
EP 34
DI 10.1038/370031a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100048
DA 2026-03-10
ER

PT J
AU DESAI, KM
   GWINN, CR
   DIAMOND, PJ
AF DESAI, KM
   GWINN, CR
   DIAMOND, PJ
TI EVIDENCE FOR MAGNETIC-FIELD-INDUCED ANISOTROPY OF THE INTERSTELLAR-MEDIUM
SO NATURE
LA English
DT Article
ID low galactic latitudes; density turbulence; radio-sources; scattering; scintillation; fluctuations; plasma; galaxy; scale; vla
AB TURBULENCE in the interstellar medium transfers energy from parsec-sized regions to much smaller scales, and may be responsible for supporting clouds against gravitational collapse(1). Fluctuations in the electron density, which trace turbulence, occur on scales ranging from 10(6) to > 10(13) cm-the largest range of spatial scales seen in natural turbulence. Despite almost thirty years of study, however, the causes and effects of interstellar turbulence are still poorly understood. Here we present observations of OH masers in the Galactic star-forming complex W49N, which we use as point sources to investigate scattering along the line of sight. The masers' images are elliptical, and aligned roughly perpendicular to the Galactic plane. This alignment suggests that the magnetic field of our Galaxy influences interstellar turbulence(2,3) by mediating the transfer of energy from large to small spatial scales.
C1 NATL RADIO ASTRON OBSERV, SOCORRO, NM 87801 USA.
C3 National Radio Astronomy Observatory (NRAO)
RP DESAI, KM (corresponding author), UNIV CALIF SANTA BARBARA, DEPT PHYS, SANTA BARBARA, CA 93106 USA.
NR 24
TC 24
Z9 25
U1 0
U2 6
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 754
EP 756
DI 10.1038/372754a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200044
DA 2026-03-10
ER

PT J
AU NICHOLS, R
   ANDREWS, PC
   ZHANG, P
   BERGSTROM, DE
AF NICHOLS, R
   ANDREWS, PC
   ZHANG, P
   BERGSTROM, DE
TI A UNIVERSAL NUCLEOSIDE FOR USE AT AMBIGUOUS SITES IN DNA PRIMERS
SO NATURE
LA English
DT Article
ID hybridization probes; duplex stability; oligonucleotides; deoxyinosine; base; analogs
AB A NON-DISCRIMINATORY base analogue, or universal base, would be an invaluable component of oligonucleotide probes and primers for solving the design problems that arise as a result of the degeneracy of the genetic code, or when only fragmentary peptide sequence data are available. We have designed an alternative to previous universal nucleoside candidates(1-9), a new analogue, 1-(2'-deoxy-beta-D-ribofuranosyl)-3-nitropyrrole (designated M; Fig. 1), which maximizes stacking while minimizing hydrogen-bonding interactions without sterically disrupting a DNA duplex. Oligonucleotides containing M at several sites were used as primers for sequencing and the polymerase chain reaction. The sequencing primer d(5'-CGT AAM CAM AAM ACM AT-3') is as effective as the exact match d(5'-CGT AAT CAG AAA ACA AT-3'). It is also possible to sequence using a primer containing M at several contiguous positions, for example d(5'-CGT AAT MMM MMM MMM AT-3'). Melting curves show that duplexes formed on hybridization of the sequences d(5';CCT TTT TMT TTT TGG-3') and d(5'-CCA AAA AXA AAA AGG-3'), where X is A, C, G or T, melted at a lower temperature than the corresponding duplexes containing only d(A.T) and d(C.G) base pairs, but showing little variation among different X bases (T-m range 3 degrees C).
C1 UNIV MICHIGAN,DEPT BIOL CHEM,ANN ARBOR,MI 48109.
   UNIV MICHIGAN,DEPT BIOL,ANN ARBOR,MI 48109.
   PURDUE UNIV,DEPT MED CHEM & PHARMACOGNOSY,W LAFAYETTE,IN 47907.
   WALTHER CANC INST,INDIANAPOLIS,IN 46208.
C3 University of Michigan System; University of Michigan; University of Michigan System; University of Michigan; Purdue University System; Purdue University; Walther Cancer Foundation
NR 14
TC 103
Z9 218
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 492
EP 493
DI 10.1038/369492a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600059
PM 8202140
DA 2026-03-10
ER

PT J
AU VISSCHER, PT
   CULBERTSON, CW
   OREMLAND, RS
AF VISSCHER, PT
   CULBERTSON, CW
   OREMLAND, RS
TI DEGRADATION OF TRIFLUOROACETATE IN OXIC AND ANOXIC SEDIMENTS
SO NATURE
LA English
DT Article
ID estuarine sediments; sulfate reduction; organic-compounds; methyl-fluoride; dimethyl ether; methane; oxidation; bacterium; hydrochlorofluorocarbons; transformations
AB THE deleterious effect of chlorofluorocarbons on stratospheric ozone has led to international cooperation to end their use(1-3). The search for acceptable alternatives has focused on hydrofluorocarbons (HFCs) or hydrochlorofluorocarbons (HCFCs) which are attractive because they have relatively short atmospheric residence times(4). HFCs and HCFCs are attacked by tropospheric hydroxyl radicals, leading to the formation of trifluoroacetate (TFA)(5). Most of the atmospheric TFA is deposited at the Earth's surface(6), where it is thought to be highly resistant to bacterial attack(5). Therefore, use of HCFCs and HFCs may lead to accumulation of TFA in soils, where it could prove toxic or inhibitory to plants and soil microbial communities(5,7). Although little is known about the toxicity of TFA, monofluoroacetate, which occurs at low levels in some plants(8) and which is susceptible to slow attack by aerobic soil microbes(9), is known to be acutely toxic(10-13). Here we report that TFA can be rapidly degraded microbially under anoxic and oxic conditions. These results imply that significant microbial sinks exist in nature for the elimination of TFA from the environment. We also show that oxic degradation of TFA leads to the formation of fluoroform, a potential ozone-depleting compound with a much longer atmospheric lifetime than the parent compounds.
RP VISSCHER, PT (corresponding author), US GEOL SURVEY,MAILSTOP 465,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA.
NR 35
TC 86
Z9 97
U1 3
U2 47
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 729
EP 731
DI 10.1038/369729a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100054
DA 2026-03-10
ER

PT J
AU SMITH, CL
   DELOTTO, R
AF SMITH, CL
   DELOTTO, R
TI VENTRALIZING SIGNAL DETERMINED BY PROTEASE ACTIVATION IN DROSOPHILA EMBRYOGENESIS
SO NATURE
LA English
DT Article
ID serine protease; dorsal; pattern; embryo; polarity; easter; genes
AB SPECIFICATION of dorsal-ventral cell fate during Drosophila embryogenesis is mediated by a signal transduction pathway1-4. Asymmetry of cell fates arises through the spatially restricted production of a ligand in an extracellular compartment called the perivitelline space5. The snake and easter genes are required for the production of the ligand17 and they encode the proenzyme form of secreted extracellular serine proteases6,7. We have examined the effect of producing a preactivated form of the snake protease on the generation of dorsal-ventral polarity. SP6 RNA microinjection experiments reveal that different cell fates acquired at cellular blastoderm can be specified by the amount and spatial distribution of activated snake protein. Our results support a protease cascade model in which localized activation of uniformly distributed protease proenzymes leads to the spatially restricted production of ligand in the perivitelline space on the ventral side of the embryo.
C1 CORNELL UNIV,GRAD SCH MED SCI,DEPT CELL BIOL,NEW YORK,NY 10021.
C3 Cornell University
RP SMITH, CL (corresponding author), SLOAN KETTERING INST CANC RES,DEPT MICROBIOL,1275 YORK AVE,NEW YORK,NY 10021, USA.
NR 17
TC 67
Z9 73
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 548
EP 551
DI 10.1038/368548a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500055
PM 8139688
DA 2026-03-10
ER

PT J
AU ADAM, D
   SCHUHMACHER, P
   SIMMERER, J
   HAUSSLING, L
   SIEMENSMEYER, K
   ETZBACH, KH
   RINGSDORF, H
   HAARER, D
AF ADAM, D
   SCHUHMACHER, P
   SIMMERER, J
   HAUSSLING, L
   SIEMENSMEYER, K
   ETZBACH, KH
   RINGSDORF, H
   HAARER, D
TI FAST PHOTOCONDUCTION IN THE HIGHLY ORDERED COLUMNAR PHASE OF A DISCOTIC LIQUID-CRYSTAL
SO NATURE
LA English
DT Article
ID transient photoconductivity; transport; polymers
AB THE search for organic materials suitable for electronic applications dates back to the early 1950s But the only organic systems known so far to show electronic charge-carrier mobilities comparable to the amorphous inorganic semiconductors that are the mainstay of the microelectronics industry are zone-refined organic single crystals(1-4). Single crystals are difficult and costly to process, however, and are not suitable for device applications. Here we show that a highly ordered columnar (stacked) phase of disk-like organic molecules can exhibit high mobilities for photoinduced charge carriers, of the order of 0.1 cm(2) V-1 s(-1)-higher than for any organic material other than single-crystal phases. Specifically, we study the helical columnar phase of 2,3,6,7,10,11-hexahexylthiotriphenylene, which can be prepared simply by cooling the isotropic liquid melt via the discotic liquid-crystal phase, in which the molecules are already stacked with a high degree of order.
C1 UNIV BAYREUTH,BIMF,D-95440 BAYREUTH,GERMANY.
   UNIV MAINZ,INST ORGAN CHEM,D-55099 MAINZ,GERMANY.
   BASF AG,D-67056 LUDWIGSHAFEN,GERMANY.
C3 University of Bayreuth; Johannes Gutenberg University of Mainz; BASF
RP ADAM, D (corresponding author), UNIV BAYREUTH,INST PHYS,D-95440 BAYREUTH,GERMANY.
NR 19
TC 1227
Z9 1295
U1 1
U2 179
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 141
EP 143
DI 10.1038/371141a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100058
DA 2026-03-10
ER

PT J
AU BEZOUSKA, K
   YUEN, CT
   OBRIEN, J
   CHILDS, RA
   CHAI, WG
   LAWSON, AM
   DRBAL, K
   FISEROVA, A
   POSPISIL, M
   FEIZI, T
AF BEZOUSKA, K
   YUEN, CT
   OBRIEN, J
   CHILDS, RA
   CHAI, WG
   LAWSON, AM
   DRBAL, K
   FISEROVA, A
   POSPISIL, M
   FEIZI, T
TI RETRACTED: OLIGOSACCHARIDE LIGANDS FOR NKR-P1 PROTEIN ACTIVATE NK CELLS AND CYTOTOXICITY (Retracted article. See vol. 500, pg. 492, 2013)
SO NATURE
LA English
DT Article; Retracted Publication
ID natural-killer-cells; mediated cyto-toxicity; gangliosides; glycolipids; recognition; molecule; mannose; glycoproteins; specificity; antibody
AB A diversity of high-affinity oligosaccharide ligands are Identified for NKR-P1, a membrane protein on natural killer (NH) cells which contains an extracellular Ca2+-dependent lectin domain. Interactions of such oligosaccharides on the target cell surface with NKR-P1 on the killer cell surface are crucial both for target cell recognition and for delivery of stimulatory or inhibitory signals linked to the NH cytolytic machinery. NK-resistant tumour cells are rendered susceptible by preincubation with liposomes expressing NKR-P1 ligands, suggesting that purging of tumour or virally infected cells in vivo may be a therapeutic possibility.
C1 NORTHWICK PK HOSP & CLIN RES CTR, GLYCOSCI LAB, GLYCOBIOL GRP, HARROW HA1 3UJ, MIDDX, ENGLAND.
   NORTHWICK PK HOSP & CLIN RES CTR, GLYCOSCI LAB, MASS SPECTROMETRY GRP, HARROW HA1 3UJ, MIDDX, ENGLAND.
   CHARLES UNIV, FAC SCI, DEPT BIOCHEM, CR-12840 PRAGUE 2, CZECH REPUBLIC.
   ACAD SCI CZECH REPUBL, INST MICROBIOL, DEPT IMMUNOL & GNOTOBIOL, CR-14220 PRAGUE 4, CZECH REPUBLIC.
C3 Imperial College London; Imperial College London; Charles University Prague; Czech Academy of Sciences; Institute of Microbiology of the Czech Academy of Sciences
NR 50
TC 268
Z9 277
U1 0
U2 39
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 150
EP 157
DI 10.1038/372150a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800047
PM 7969447
DA 2026-03-10
ER

PT J
AU LYNE, AG
   LORIMER, DR
AF LYNE, AG
   LORIMER, DR
TI HIGH BIRTH VELOCITIES OF RADIO PULSARS
SO NATURE
LA English
DT Article
ID gamma-ray bursts; neutron-stars; proper motions; origin
AB NEUTRON stars are usually born during the supernova explosion of a massive star. Any small asymmetry during the explosion can result in a substantial 'kick' velocity(1) to the neutron star. Pulsars (rapidly rotating, magnetized neutron stars) have long been known to have high space velocities(2,3), but new measurements of proper motion(4-6), adoption of a new distance scale for the pulsars(7) and the realization that some previous velocities were systematically low by a factor of 2 (ref. 8) have prompted us to reassess these velocities. Here, taking into account a strong selection effect that makes the observed velocities unrepresentative of those acquired at birth(9), we arrive at a mean pulsar birth velkocity of 450 +/- 90 km s(-1). This exceeds the escape velocity from binary systems, globular clusters and the Galaxy, and so will affect our understanding of the retention of neutron stars in these systems. Those neutron stars that are retained by the Milky Way will be distributed more isotropically than has been thought(10-12), which may result in a distribution like that of the gamma-ray burst sources.
RP LYNE, AG (corresponding author), UNIV MANCHESTER,NUFFIELD RADIO ASTRON LABS,JODRELL BANK,MACCLESFIELD SK11 9DL,CHESHIRE,ENGLAND.
NR 25
TC 777
Z9 815
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 127
EP 129
DI 10.1038/369127a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100041
DA 2026-03-10
ER

PT J
AU CARLSON, CA
   DUCKLOW, HW
   MICHAELS, AF
AF CARLSON, CA
   DUCKLOW, HW
   MICHAELS, AF
TI ANNUAL FLUX OF DISSOLVED ORGANIC-CARBON FROM THE EUPHOTIC ZONE IN THE NORTHWESTERN SARGASSO SEA
SO NATURE
LA English
DT Article
ID temperature catalytic-oxidation; time-series; bermuda; doc; seawater; ocean; particulate; nitrate; oxygen
AB THE export of biogenic carbon from the upper ocean is responsible for maintaining the vertical gradient of dissolved inorganic carbon and thus indirectly for regulating the level of atmospheric CO2 (ref. 1). Large, rapidly sinking particles are thought to dominate this export(2), and this sinking flux has been thought to balance new production(3). Recent measurements of particle export(4-6) and estimates of new production(7-9) have questioned this picture, however. Here we report measurements of dissolved organic carbon (DOC) off Bermuda, which provide strong support for the idea(10-15) that this component of oceanic carbon is also an important and dynamic part of the ocean carbon cycle. We find that DOC accumulates in the early spring owing to increased primary production, and is partially consumed in the summer and autumn. The DOC that escapes remineralization is exported from the surface ocean the following winter, and we estimate this export to be equal to or greater than the measured particle flux, allowing us to close the annual vertical carbon budget for this site to within a factor of two. Our observations should be applicable to other temperate, sub-polar and continental-shelf regions of the world ocean which exhibit convective mixing and vernal restratification.
C1 VIRGINIA INST MARINE SCI,COLL WILLIAM & MARY,GLOUCESTER POINT,VA 23062.
   BERMUDA BIOL STN RES INC,ST GEORGES GE01,BERMUDA.
C3 William & Mary; Virginia Institute of Marine Science
RP CARLSON, CA (corresponding author), UNIV MARYLAND,HORN POINT ENVIRONM LAB,POB 775,CAMBRIDGE,MD 21613, USA.
NR 31
TC 589
Z9 665
U1 0
U2 85
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 405
EP 408
DI 10.1038/371405a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500038
DA 2026-03-10
ER

PT J
AU HAWKEN, MJ
   GEGENFURTNER, KR
   TANG, C
AF HAWKEN, MJ
   GEGENFURTNER, KR
   TANG, C
TI CONTRAST DEPENDENCE OF COLOR AND LUMINANCE MOTION MECHANISMS IN HUMAN VISION
SO NATURE
LA English
DT Article
ID perception; detectors; movement; model
AB CONVENTIONAL VieWS Of visual perception propose a colour-blind pathway conveying motion information and a motion-blind pathway carrying colour information1,2. Recent studies show that motion perception is not always colour blind, is partially depen dent on attention5,6, can show considerable perceptual slowing around isoluminance7-9 and is contrast-dependent10,11.  If there is a single motion pathway, receiving luminance and chromatic input, then the dependence of relative perceived velocity on relative stimulus contrast should be the same for both luminance and chromatic targets. Here we provide a distinctive characterization of the motion mechanisms using a robust velocity-matching task. A relative contrast scale allows direct comparison of the performance with luminance and chromatic targets. The results show that the perceived speed of slowly moving coloured targets at isoluminance has a steep contrast dependence. The perceived speed of slowly moving luminance tar-ets shows a much lower contrast dependence. At high speeds the contrast dependence is low for both luminance and isoluminant stimuli, although the behaviour is unlike either of the slow mechanisms. The results suggest two independent pathways that perceive slowly moving targets: one is luminance-sensitive and the other is colour-sensitive. Fast movement is signalled via a single motion pathway that is contrast-invariant and not colour blind.
C1 NYU,HOWARD HUGHES MED INST,NEW YORK,NY 10003.
C3 New York University; Howard Hughes Medical Institute
RP HAWKEN, MJ (corresponding author), NYU,CTR NEURAL SCI,4 WASHINGTON PL,NEW YORK,NY 10003, USA.
NR 20
TC 120
Z9 123
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 268
EP 270
DI 10.1038/367268a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400055
PM 8121491
DA 2026-03-10
ER

PT J
AU WAGA, S
   HANNON, GJ
   BEACH, D
   STILLMAN, B
AF WAGA, S
   HANNON, GJ
   BEACH, D
   STILLMAN, B
TI THE P21 INHIBITOR OF CYCLIN-DEPENDENT KINASES CONTROLS DNA-REPLICATION BY INTERACTION WITH PCNA
SO NATURE
LA English
DT Article
ID cell nuclear antigen; polymerase-delta; strand synthesis; protein; invitro; p53; initiation; subunit; repair; origin
AB THE p53 tumour-suppressor protein controls the expression of a gene encoding the p21 cyclin-dependent protein kinase (CDK) regulator(1-6). Levels of p21 protein are increased in senescent cells and p21 overexpression blocks the growth of tumour cells(1,3,7). In normal human cells, but not in many tumour cells, p21 exists in a guaternary complex with a cyclin, a CDK, and the proliferating-cell nuclear antigen (PCNA)(5,8). p21 controls CDK activity, thereby affecting cell-cycle control(2-4,6), whereas PCNA functions in both DNA replication(9-12) and repair(13). Here we use simian virus 40 DNA replication in vitro to show that p21 directly inhibits PCNA-dependent DNA replication in the absence of a cyclin/CDK. Furthermore, p21 blocks the ability of PCNA to activate DNA polymerase delta, the principal replicative DNA polymerase. This regulation results from a direct interaction between p21 and PCNA. Thus, during p53-mediated suppression of cell proliferation, p21 and PCNA mag be important for coordinating cell-cycle progression, DNA replication and repair of damaged DNA.
C1 HOWARD HUGHES MED INST, COLD SPRING HARBOR, NY 11724 USA.
C3 Howard Hughes Medical Institute
RP WAGA, S (corresponding author), COLD SPRING HARBOR LAB, POB 100, BUNGTOWN RD, COLD SPRING HARBOR, NY 11724 USA.
NR 29
TC 1678
Z9 1812
U1 34
U2 555
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 574
EP 578
DI 10.1038/369574a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400054
PM 7911228
DA 2026-03-10
ER

PT J
AU DEJAGER, OC
   STECKER, FW
   SALAMON, MH
AF DEJAGER, OC
   STECKER, FW
   SALAMON, MH
TI ESTIMATE OF THE INTERGALACTIC INFRARED RADIATION-FIELD FROM GAMMA-RAY OBSERVATIONS OF THE GALAXY MRK421
SO NATURE
LA English
DT Article
ID markarian-421
AB THE magnitude of the intergalactic infrared radiation field (IIRF) is of fundamental importance to investigations of the evolution of galaxies. Bursts of star formation, which seem to be critically important to galaxy evolution, are characterized by large infrared luminosities(1), yet ie have little knowledge of the frequency and intensity of starbursts in the early Universe. Unfortunately, direct observational determinations of the IIRF are plagued by the difficulty of separating the extragalactic emission from Galactic foreground radiation and the zodiacal light in the Solar System, and have so far produced only upper limits that are far above theoretical expectations(2). We have previously proposed(3) a way to use ground-based observations of high-energy gamma-rays to probe the IIRF, and here we apply our method to the spectrum(4,5) of the BL Lac object Mrk421. The intensity we derive for the IIRF is consistent with the conversion of at least 30% of the energy from stellar nucleosynthesis to infrared radiation, both from emission by cool stars and as a result of absorption and re-emission by interstellar dust grains.
C1 NASA, GODDARD SPACE FLIGHT CTR, HIGH ENERGY ASTROPHYS LAB, GREENBELT, MD 20771 USA.
   UNIV UTAH, INST HIGH ENERGY ASTROPHYS, SALT LAKE CITY, UT 84112 USA.
   UNIV UTAH, DEPT PHYS, SALT LAKE CITY, UT 84112 USA.
C3 National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center; Utah System of Higher Education; University of Utah; Utah System of Higher Education; University of Utah
RP DEJAGER, OC (corresponding author), POTCHEFSTROOM UNIV CHRISTIAN HIGHER EDUC, DEPT PHYS, SPACE RES UNIT, POTCHEFSTROOM 2520, SOUTH AFRICA.
NR 24
TC 63
Z9 66
U1 0
U2 1
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 294
EP 296
DI 10.1038/369294a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900040
DA 2026-03-10
ER

PT J
AU SENGPIEL, F
   BLAKEMORE, C
AF SENGPIEL, F
   BLAKEMORE, C
TI INTEROCULAR CONTROL OF NEURONAL RESPONSIVENESS IN CAT VISUAL-CORTEX
SO NATURE
LA English
DT Article
ID cross-orientation inhibition; binocular-rivalry; striate cortex; cells; adaptation; organization; model
AB NEURONS in the cat primary visual cortex are selective for particular contour orientations' but their responsiveness can vary under certain conditions. After prolonged stimulation (adaptation), the contrast sensitivity of cortical cells is reduced(2-5) and the 'gain' (the strength of response as a function of contrast) falls(5-6). The response to an optimal contour is also reduced when,a different stimulus is superimposed on the receptive field in the same eye(7-9). Here we report that the sudden appearance of an inappropriate stimulus in one eye can interocularly suppress the activity of cortical neurons if they are already responding to an optimally oriented stimulus in the other eye. In strabismic cats, whose cortical neurons lack binocular facilitation, even contours of similar orientation shown to the two eyes trigger such suppression. This interocular control of cortical responsiveness could serve to veto signals from one eye under conditions that would otherwise cause double vision and perceptual confusion.
RP SENGPIEL, F (corresponding author), UNIV OXFORD,PHYSIOL LAB,PARKS RD,OXFORD OX1 3PT,ENGLAND.
NR 30
TC 94
Z9 102
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 847
EP 850
DI 10.1038/368847a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700069
PM 8159244
DA 2026-03-10
ER

PT J
AU LYNCHSTIEGLITZ, J
   FAIRBANKS, RG
AF LYNCHSTIEGLITZ, J
   FAIRBANKS, RG
TI A CONSERVATIVE TRACER FOR GLACIAL OCEAN CIRCULATION FROM CARBON-ISOTOPE AND PALAEO-NUTRIENT MEASUREMENTS IN BENTHIC FORAMINIFERA
SO NATURE
LA English
DT Article
ID atmospheric co2; pacific; delta-c-13; cadmium; c-13
AB THE ratio of cadmium to calcium (Cd/Ca) and the carbon isotope ratio (delta(13)C) in, the calcite tests of benthic foraminifera both record nutrient distributions in the ocean(1,2). Strict interpretation of both delta(13)C and Cd as nutrient tracers has led to conflicting views of glacial ocean circulation(3-5). Here we show that, when one takes into account the fact that delta(13)C reflects air-sea exchange as web as nutrient distributions, these two proxies can provide complementary information about the movement of deep water in the glacial ocean. We use the Cd concentration (assumed to be controlled primarily by biological cycling) to infer the age history of glacial deep water, and deduce the sources of deep water from the carbon isotope air-sea exchange signature, a conservative tracer that we construct using both Cd and delta(13)C measurements. Our analysis suggests that there were at least two sources of glacial deep water: a less dense component originating in the North Atlantic Ocean, and a more dense component which may have originated in the Pacific Ocean. As well as demonstrating the potential of this approach, our findings provide further support for a Pacific glacial deep water source, evidence for which has until now been both scarce and conflicting(3,5-12).
C1 COLUMBIA UNIV, DEPT GEOL SCI, PALISADES, NY 10964 USA.
C3 Columbia University
RP LYNCHSTIEGLITZ, J (corresponding author), COLUMBIA UNIV, LAMONT DOHERTY EARTH OBSERV, PALISADES, NY 10964 USA.
NR 25
TC 73
Z9 84
U1 0
U2 20
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 308
EP 310
DI 10.1038/369308a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900045
DA 2026-03-10
ER

PT J
AU VERSELIS, VK
   GINTER, CS
   BARGIELLO, TA
AF VERSELIS, VK
   GINTER, CS
   BARGIELLO, TA
TI OPPOSITE VOLTAGE GATING POLARITIES OF 2 CLOSELY-RELATED CONNEXINS
SO NATURE
LA English
DT Article
ID dependent junctional conductance; gap junction; molecular-cloning; xenopus oocytes; cell channels; expression; membrane
AB THE molecular mechanisms underlying the voltage dependence of intercellular channels formed by the family of vertebrate gap junction proteins (connexins) are unknown. All vertebrate gap junctions are sensitive to the voltage difference between the cells, defined as the transjunctional voltage, V-j (refs 1, 2), and most appear to gate by the separate actions of their component hemichannels(3-8). The heterotypic Cx32/Cx26 junction displays an unpredicted rectification that was reported to represent a novel V-j dependence created by hemichannel interactions, mediated in part by the first extracellular loop E1 (ref. 9). Here we show that aspects of the rectification of Cx32/Cx26 junctions are explained by opposite gating polarities of the component hemichannels, and that the opposite gating polarity of Cx32 and Cx26 results from a charge difference in a single amino-acid residue located at the second position in the N terminus. We also shea that charge substitutions at the border of the first transmembrane (M1) and E1 domains can reverse gating polarity and suppress the effects of a charge substitution at the N terminus. We conclude that the combined actions of residues at the N terminus and M1/E1 border form a charge complex that is probably an integral part of tbe connexin voltage sensor. A consistent correlation between charge substitution and gating polarity indicates that Cx26 and Cx32 voltage sensors are oppositely charged and that both move towards the cytoplasm upon hemichannel closure.
RP VERSELIS, VK (corresponding author), ALBERT EINSTEIN COLL MED, DEPT NEUROSCI, 1300 MORRIS PK AVE, BRONX, NY 10461 USA.
NR 27
TC 311
Z9 345
U1 0
U2 3
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 348
EP 351
DI 10.1038/368348a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500050
PM 8127371
DA 2026-03-10
ER

PT J
AU MAENO, Y
   HASHIMOTO, H
   YOSHIDA, K
   NISHIZAKI, S
   FUJITA, T
   BEDNORZ, JG
   LICHTENBERG, F
AF MAENO, Y
   HASHIMOTO, H
   YOSHIDA, K
   NISHIZAKI, S
   FUJITA, T
   BEDNORZ, JG
   LICHTENBERG, F
TI SUPERCONDUCTIVITY IN A LAYERED PEROVSKITE WITHOUT COPPER
SO NATURE
LA English
DT Article
ID electrical-property; transition; sr2ruo4; state
AB FOLLOWING the discovery of superconductivity at similar to 30K in La2-xBaxCuO4 (ref. 1), a large number of related compounds have been found that are superconducting at relatively high temperatures. The feature common to all of these materials is a layered crystal structure based on a perovskite template and containing planar networks of copper and oxygen. This raises the question of whether superconductivity can occur in layered perovskites that do not contain copper. To the best of our knowledge, no such material has been found to date, despite nearly a decade of searching. We describe here the discovery of superconductivity in Sr2RuO4, a layered perovskite isostructural with La2-xBaxCuO4 (Fig. 1). Our results demonstrate that the presence of copper is not a prerequisite for the existence of superconductivity in a layered perovskite. But the low value of the superconducting transition temperature (T-c= 0.93 K) points towards a special role for copper in the high-temperature superconductors.
C1 IBM CORP,DIV RES,ZURICH RES LAB,CH-8803 RUSCHLIKON,SWITZERLAND.
C3 International Business Machines (IBM); IBM Switzerland
RP MAENO, Y (corresponding author), HIROSHIMA UNIV,DEPT PHYS,HIGASHIHIROSHIMA 724,JAPAN.
NR 19
TC 2269
Z9 2447
U1 5
U2 561
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 532
EP 534
DI 10.1038/372532a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200046
DA 2026-03-10
ER

PT J
AU WARD, Y
   GUPTA, S
   JENSEN, P
   WARTMANN, M
   DAVIS, RJ
   KELLY, K
AF WARD, Y
   GUPTA, S
   JENSEN, P
   WARTMANN, M
   DAVIS, RJ
   KELLY, K
TI CONTROL OF MAP KINASE ACTIVATION BY THE MITOGEN-INDUCED THREONINE/TYROSINE PHOSPHATASE PAC1
SO NATURE
LA English
DT Article
ID growth-factor receptor; protein-kinase; encoded protein; phosphorylation; sequence; gene
AB INTRACELLULAR Signalling following mitogenic stimulation of quiescent cells involves the initiation of a phosphorylation cascade that leads to the rapid and reversible activation of the mitogen-activated protein (MAP) kinases ERK1 and ERK2 (refs 1, 2). MAP kinase activation is mediated by dual phosphorylation within the motif Thr-Glu-Tyr by MAP kinase kinase (MEK)(3). Following activation, the MAP kinases translocate into the nucleus where they phosphorylate several transduction targets, including transcription factors(4-7). We have previously identified PAC1 as an immediate-early mitogen-inducible tyrosine phosphatase in nuclei of T cells(8). Here we present several lines of evidence indicating that PAC1 is a physiologically relevant MAP kinase phosphatase. Recombinant PAC1 in vitro is a dual-specific Thr/Tyr phosphatase with stringent substrate specificity for MAP kinase. Constitutive expression of PAC1 in vivo leads to inhibition of MAP kinase activity normally stimulated by epidermal growth factor, phorbol myristyl acetate, or T-cell receptor crosslinking. The inactivation of MAP kinase by PAC1 results in inhibition of MAP kinase-regulated reporter gene expression.
C1 NCI,PATHOL LAB,BETHESDA,MD 20892.
   UNIV MASSACHUSETTS,SCH MED,HOWARD HUGHES MED INST,DEPT BIOCHEM & MOLEC BIOL,WORCESTER,MA 01605.
C3 National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI); University of Massachusetts System; University of Massachusetts Worcester; Howard Hughes Medical Institute
NR 25
TC 322
Z9 340
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 651
EP 654
DI 10.1038/367651a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800056
PM 8107850
DA 2026-03-10
ER

PT J
AU WILLETT, SD
   BEAUMONT, C
AF WILLETT, SD
   BEAUMONT, C
TI SUBDUCTION OF ASIAN LITHOSPHERIC MANTLE BENEATH TIBET INFERRED FROM MODELS OF CONTINENTAL COLLISION
SO NATURE
LA English
DT Article
ID wave velocity structure; tectonic implications; himalayan arc; indian shield; plateau; evolution; crust; belts; deformation; zone
AB The relative northward motion of the Indian subcontinent that followed the onset of continental collision with Asia has produced extensive deformation of the Earth's crust, giving rise to the world's highest mountains in the Himalayan chain and the world's largest high-elevation region, the Tibetan plateau. The formation of the broad mountain belt implies that, contrary to the original tenets of plate tectonics, the lithospheric plates have experienced widespread deformation far from the plate boundary(1). Several models have been proposed(2-6) to explain the manner in which this post-collisional deformation is distributed within the continental lithosphere of the Indian and Asian plates. Here we propose an alternative model in which subduction of the Asian lithospheric mantle develops following the collision of India. Our model is supported by numerical calculations of crustal deformation and thickening, and is consistent with available geological and geophysical data(7-9). This picture suggests that lithospheric mantle is not deformed along with the crust, and would imply that continental collision zones are more analogous to oceanic subduction zones than was previously believed.
RP WILLETT, SD (corresponding author), DALHOUSIE UNIV,DEPT OCEANOG,HALIFAX B3H 4J1,NS,CANADA.
NR 48
TC 205
Z9 242
U1 0
U2 53
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 642
EP 645
DI 10.1038/369642a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900053
DA 2026-03-10
ER

PT J
AU DIAZBENJUMEA, FJ
   COHEN, B
   COHEN, SM
AF DIAZBENJUMEA, FJ
   COHEN, B
   COHEN, SM
TI CELL-INTERACTION BETWEEN COMPARTMENTS ESTABLISHES THE PROXIMAL-DISTAL AXIS OF DROSOPHILA LEGS
SO NATURE
LA English
DT Article
ID segment-polarity gene; limb development; pattern-formation; imaginal disks; decapentaplegic gene; engrailed gene; wingless; melanogaster; expression; less
AB THE appendage primordia of Drosophila are subdivided into compartments(1-4) by the localized expression of transcription factors(5-7). Interaction between cells in adjacent compartments establishes organizing centres responsible for generating spatial pattern and promoting cell proliferation in the developing appendages(7-9). Localized expression of hedgehog (hh) in the posterior compartment of the leg: imaginal disc directs expression of wingless (wg) in ventral-anterior cells and decapentaplegic (dpp) in dorsal-anterior cells near the anterior-posterior compartment boundary(8); wg then acts to specify ventral cell fate(10-12) and to organize the dorsal-ventral axis of the leg(13,14). Interaction between wg-expressing ventral cells and dorsal cells near the anterior-posterior compartment boundary promotes axis formation in the leg(14,15). Here we show that the combined action of log-expressing cells in the ventral-anterior compartment and dpp-expressing cells in the dorsal-anterior compartment activates expression of Distal-less, a gene required for proximal-distal axis formation in the limbs. These results demonstrate that sequential interaction between anterior-posterior and dorsal-ventral compartments establishes the proximal-distal axis of the limbs.
RP DIAZBENJUMEA, FJ (corresponding author), EUROPEAN MOLEC BIOL LAB,DIFFERENTIAT PROGRAMME,POSTFACH 102209,D-69012 HEIDELBERG,GERMANY.
NR 29
TC 303
Z9 327
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 175
EP 179
DI 10.1038/372175a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800055
PM 7969450
DA 2026-03-10
ER

PT J
AU WEAVER, AJ
   HUGHES, TMC
AF WEAVER, AJ
   HUGHES, TMC
TI RAPID INTERGLACIAL CLIMATE FLUCTUATIONS DRIVEN BY NORTH-ATLANTIC OCEAN CIRCULATION
SO NATURE
LA English
DT Article
ID deep circulation; variability; models
AB RECENT data from the GRIP ice core1-3 in Greenland suggest that the climate of the last (Eemian) interglacial period was much less stable than that of the present interglacial. Rapid transitions between warm and cold periods were found to occur on timescales of just a few decades. The North Atlantic climate during the Eemian period was also shown to be characterized by three states, respectively warmer than, similar to and colder than today1,2. Recent data from the nearby GISP2 ice core have revealed some discrepancies with these findings, which remain to be resolved4,5. Here we present simulations using an idealized global ocean model, which suggest that the North Atlantic ocean has three distinct circulation modes, each of which corresponds to a distinct climate state. We find that adding a simple random component to the mean freshwater flux (which forces circulation) can induce rapid transitions between these three modes. We suggest that increased variability in the hydrological cycle associated with the warmer Eemian climate could have caused transition between these distinct modes in the North Atlantic circulation, which may in turn account for the apparent rapid variability of the Eemian climate.
RP WEAVER, AJ (corresponding author), UNIV VICTORIA,SCH EARTH & OCEAN SCI,POB 1700,VICTORIA V8W 2Y2,BC,CANADA.
NR 29
TC 109
Z9 111
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 447
EP 450
DI 10.1038/367447a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900050
DA 2026-03-10
ER

PT J
AU TAKAHAMA, Y
   SUZUKI, H
   KATZ, KS
   GRUSBY, MJ
   SINGER, A
AF TAKAHAMA, Y
   SUZUKI, H
   KATZ, KS
   GRUSBY, MJ
   SINGER, A
TI POSITIVE SELECTION OF CD4+ T-CELLS BY TCR LIGATION WITHOUT AGGREGATION EVEN IN THE ABSENCE OF MHC
SO NATURE
LA English
DT Article
ID cd3/t-cell receptor complex; class-ii molecules; monoclonal-antibody; antigen receptor; immature thymocytes; negative selection; transgenic mice; cross-linking; thymus; beta
AB THE developmental fate of immature thymocytes is determined by the specificity of their T-cell antigen receptors (TCRs). Immature CD4(+)8(+) thymocytes are positively selected to differentiate into mature T cells by recognition of peptides associated with major histocompatibility complex (MHC) encoded molecules(7-10) on But neither the identity of molecules transducing positive selection signals nor the nature of the signals themselves is fully known. Here we report that direct ligation of TCR molecules by monoclonal antibodies specific for either clonotypic or CD3 chains can signal immature thymocytes to differentiate into mature CD4(+)8(-) T cells, even in the absence of MHC expression and MHC-dependent CD4 co-receptor signalling. Moreover, we show that TCR engagement induces positive selection signals only in the absence of TCR aggregation and that TCR aggregation is inhibitory for positive selection. Thus, low valency of TCR crosslinking is a critical parameter(15), distinguishing positive selection from other TCR-mediated signalling events.
C1 NCI, EXPTL IMMUNOL BRANCH, BETHESDA, MD 20892 USA.
   SYNTEX INST IMMUNOL, NIIHARI 30041, JAPAN.
   HARVARD UNIV, SCH PUBL HLTH, DEPT CANC BIOL, BOSTON, MA 02115 USA.
   HARVARD UNIV, SCH MED, DEPT RHEUMATOL, BOSTON, MA 02115 USA.
C3 National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI); Harvard University; Harvard T.H. Chan School of Public Health; Harvard University; Harvard Medical School
NR 46
TC 78
Z9 82
U1 0
U2 3
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 67
EP 70
DI 10.1038/371067a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100052
PM 7915400
DA 2026-03-10
ER

PT J
AU KAUSHANSKY, K
   LOK, S
   HOLLY, RD
   BROUDY, VC
   LIN, N
   BAILEY, MC
   FORSTROM, JW
   BUDDLE, MM
   OORT, PJ
   HAGEN, FS
   ROTH, GJ
   PAPAYANNOPOULOU, T
   FOSTER, DC
AF KAUSHANSKY, K
   LOK, S
   HOLLY, RD
   BROUDY, VC
   LIN, N
   BAILEY, MC
   FORSTROM, JW
   BUDDLE, MM
   OORT, PJ
   HAGEN, FS
   ROTH, GJ
   PAPAYANNOPOULOU, T
   FOSTER, DC
TI PROMOTION OF MEGAKARYOCYTE PROGENITOR EXPANSION AND DIFFERENTIATION BY THE C-MPL LIGAND THROMBOPOIETIN
SO NATURE
LA English
DT Article
ID stem-cell factor; human interleukin-6; growth-factors; kit ligand; invivo; erythropoietin; invitro; purification; synergism; mice
AB THE development of blood cells including expansion of megakaryocyte progenitor cells requires the interplay of marrow stromal cells and polypeptide cytokines(1-10). Recently, characterization of c-Mpl, the receptor encoded by the proto-oncogene c-mpl, revealed structural homology with the haematopoietic cytokine receptor family(11), and its involvement in megakaryocyte development(12). We report here that the ligand for c-Mpl(13) is relatively lineage specific, works both alone and synergistically with early acting cytokines to support megakaryocyte colony formation, and acts at a late stage of development to increase megakaryocyte size, polyploidization and expression of differentiation markers. In vivo, c-Mpl ligand stimulates platelet production by greatly expanding marrow and splenic megakaryocytes and their progenitors, and by shifting the distribution of megakaryocyte ploidy to higher values. Thus, as c-Mpl ligand has the expected characteristics of the major regulator of megakaryocyte development, we propose that it be termed thrombopoietin.
C1 ZYMOGENET INC,SEATTLE,WA 98105.
C3 Zymogenet Inc.
RP KAUSHANSKY, K (corresponding author), UNIV WASHINGTON,SCH MED,DIV HEMATOL,SEATTLE,WA 98195, USA.
NR 28
TC 954
Z9 1082
U1 1
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 568
EP 571
DI 10.1038/369568a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400052
PM 8202159
DA 2026-03-10
ER

PT J
AU JIN, YS
   HOSKINS, R
   HORVITZ, HR
AF JIN, YS
   HOSKINS, R
   HORVITZ, HR
TI CONTROL OF TYPE-D GABAERGIC NEURON DIFFERENTIATION BY C-ELEGANS UNC-30 HOMEODOMAIN PROTEIN
SO NATURE
LA English
DT Article
ID caenorhabditis-elegans; nervous-system; gene encodes
AB THE Caenorhabditis elegans gene unc-30 is required for the develop ment and functioning of the 19 inhibitory GABAergic (gamma-aminobutyric-acid-secreting) type D motor neurons, which control locomotion(1-4). In unc-30 mutants the D neurons lack GABA(2) and have defects in axonal pathfinding and synaptic connections (J. White, personal communication). We report here that unc-30 encodes a homeodomain protein that is present in the nuclei of the D neurons at high levels in young larvae, in which the motor circuitry is formed, and at low levels in older animals. The UNC-30 protein is also present in six non-GABAergic neurons and is absent from the seven non-D-type GABAergic neurons. Ectopic expression of unc-30 induced GABA expression in cells that are normally not GABAergic. We propose that unc-30 functions as a transcriptional regulator within the type D neurons to control their terminal differentiation and that unc-30 is sufficient in some but not all cell types to induce GABA expression.
C1 MIT,HOWARD HUGHES MED INST,DEPT BIOL,CAMBRIDGE,MA 02139.
   MRC,MOLEC BIOL LAB,CAMBRIDGE CB2 2QH,ENGLAND.
C3 Howard Hughes Medical Institute; Massachusetts Institute of Technology (MIT); MRC Laboratory Molecular Biology
NR 30
TC 201
Z9 247
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 780
EP 783
DI 10.1038/372780a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200053
PM 7997265
DA 2026-03-10
ER

PT J
AU YAO, A
AF YAO, A
TI SCIENCE PARKS AS A FORCE IN EMPLOYMENT - TAIWAN PARK ATTRACTS RESEARCHERS HOME
SO NATURE
LA English
DT Article
C1 HSINCHU SCI PK ADM,HSINCHU 30077,TAIWAN.
NR 0
TC 0
Z9 0
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 171
EP 172
DI 10.1038/368171a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000076
DA 2026-03-10
ER

PT J
AU MIRABEL, IF
   RODRIGUEZ, LF
AF MIRABEL, IF
   RODRIGUEZ, LF
TI A SUPERLUMINAL SOURCE IN THE GALAXY
SO NATURE
LA English
DT Article
AB APPARENT velocities greater than the speed of light (superluminal motion) have been inferred for radio-emitting components in a number of distant quasars and active galactic nuclei(1). These components move away from the central sources (generally thought to be super-massive black holes) at rates that seem to imply velocities greater than c. The accepted explanation is that clouds of plasma are ejected in opposite directions from the central source at speeds close to (but less than) that of light, and that relativistic effects lead to the apparent superluminal motion(2). But the extreme distance of the objects observed so far introduces many uncertainties into this interpretation(3). Here we present observations of the first apparent superluminal motion ever detected in a source within our own Galaxy. The optical, infrared and X-ray properties(4,5) of the counterpart suggest that the source is either a neutron star or a black hole that is ejecting matter in a process similar to, but on a smaller scale than that seen in quasars. Because of its relative proximity, this superluminal microquasar may offer the best opportunity to gain a general understanding of relativistic ejections seen elsewhere in the Universe.
C1 NATL RADIO ASTRON OBSERV, SOCORRO, NM 87801 USA.
   Univ Nacl Autonoma Mexico, ASTRON INST, MEXICO CITY, MEXICO.
C3 National Radio Astronomy Observatory (NRAO); Universidad Nacional Autonoma de Mexico
RP MIRABEL, IF (corresponding author), CTR ETUD SACLAY, DAPNIA, DSM, CEA, SERV ASTROPHYS, F-91191 GIF SUR YVETTE, FRANCE.
NR 19
TC 1049
Z9 1091
U1 0
U2 16
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 46
EP 48
DI 10.1038/371046a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100044
DA 2026-03-10
ER

PT J
AU HOFSTRA, RMW
   LANDSVATER, RM
   CECCHERINI, I
   STULP, RP
   STELWAGEN, T
   LUO, Y
   PASINI, B
   HOPPENER, JWM
   VANAMSTEL, HKP
   ROMEO, G
   LIPS, CJM
   BUYS, CHCM
AF HOFSTRA, RMW
   LANDSVATER, RM
   CECCHERINI, I
   STULP, RP
   STELWAGEN, T
   LUO, Y
   PASINI, B
   HOPPENER, JWM
   VANAMSTEL, HKP
   ROMEO, G
   LIPS, CJM
   BUYS, CHCM
TI A MUTATION IN THE RET PROTOONCOGENE ASSOCIATED WITH MULTIPLE ENDOCRINE NEOPLASIA TYPE-2B AND SPORADIC MEDULLARY-THYROID CARCINOMA
SO NATURE
LA English
DT Article
ID chromosome-10; linkage; domains; kinase
AB MULTIPLE endocrine neoplasia type 2 (MEN 2) comprises three clinically distinct, dominantly inherited cancer syndromes. MEN 2A patients develop medullary thyroid carcinoma (MTC) and phaeochromocytoma. MEN 2B patients show in addition ganglioneuromas of the gastrointestinal tract and skeletal abnormalities. In familial MTC, only the thyroid is affected. Germ-line mutations of the RET proto-oncogene have recently been reported in association with MEN 2A and familial MTC1,2. All mutations occurred within codons specifying cysteine residues in the transition point between the RET protein extracellular and transmembrane domains. We now show that MEN 2B is also associated with mutation of the RET proto-oncogene. A mutation in codon 664, causing the substitution of a threonine for a methionine in the tyrosine kinase domain of the protein, was found in all nine unrelated MEN 2B patients studied. The same mutation was found in six out of 18 sporadic tumours.
C1 UNIV GRONINGEN,DEPT MED GENET,ANT DEUSINGLAAN 4,9713 AW GRONINGEN,NETHERLANDS.
   UNIV UTRECHT HOSP,CTR CLIN GENET,DEPT INTERNAL MED & PATHOL,3584 CX UTRECHT,NETHERLANDS.
   INST G GASLINI,GENET MOLEC LAB,I-16148 GENOA,ITALY.
C3 University of Groningen; Utrecht University; Utrecht University Medical Center; University of Genoa; IRCCS Istituto Giannina Gaslini
NR 14
TC 1003
Z9 1058
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 375
EP 376
DI 10.1038/367375a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000069
PM 7906866
DA 2026-03-10
ER

PT J
AU VU, TH
   HOFFMAN, AR
AF VU, TH
   HOFFMAN, AR
TI PROMOTER-SPECIFIC IMPRINTING OF THE HUMAN INSULIN-LIKE GROWTH FACTOR-II GENE
SO NATURE
LA English
DT Article
ID allele-specific methylation; beckwith-wiedemann syndrome; wilms-tumor; igf2 gene; mouse; relaxation; embryogenesis; cancer
AB GENOMIC imprinting is a mechanism whereby only one of the two parental alleles is expressed. Loss or relaxation of genomic imprinting has been proposed as an epigenetic mechanism for oncogenesis in a variety of human tumours(1-6). Although the mechanism of imprinting is unknown, differential CpG methylation of the parental alleles has been implicated(7-12). The human insulinlike growth factor-II (IGF2) gene, which is transcribed from four promoters, P1-P4 (ref. 13), is imprinted in fetal liver(14,15) but biallelic expression occurs in adult liver(16). Like most tissues, fetal liver uses primarily promoters P3 and P4 (ref. 17). Adult liver, however, transcribes IGF2 from promoter P1, and it has been suggested that the recruitment of P1 may be responsible for the absence of imprinting in human liver, and in choroid plexus and leptomeninges(18). We report here that in liver and chondrocytes, IGF2 transcripts from promoter P1 are always derived from both parental alleles, whereas transcripts from promoters P2, P3 and P4 are always from one parental allele. These findings demonstrate that imprinting and a lack of imprinting can both occur within a single gene in a single tissue, suggesting that regional imprinting factors may be important.
C1 STANFORD UNIV,DEPT MED,PALO ALTO,CA 94304.
C3 Stanford University
RP VU, TH (corresponding author), VET ADM MED CTR,MED SERV,3801 MIRANDA AVE,PALO ALTO,CA 94304, USA.
NR 24
TC 214
Z9 227
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 714
EP 717
DI 10.1038/371714a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300060
PM 7935819
DA 2026-03-10
ER

PT J
AU HEMLEY, RJ
   SOOS, ZG
   HANFLAND, M
   MAO, HK
AF HEMLEY, RJ
   SOOS, ZG
   HANFLAND, M
   MAO, HK
TI CHARGE-TRANSFER STATES IN DENSE HYDROGEN
SO NATURE
LA English
DT Article
ID solid molecular-hydrogen; megabar pressures; vibrational dynamics; phase-transition; metallization; deuterium; gpa; spectroscopy; temperature; absorption
AB THE electronic properties of hydrogen, from the gas phase to the solid state, are fundamental to our understanding of the chemical bond(1). The strong covalent bond of diatomic hydrogen persists in low-density condensed phases, where the molecules interact very weakly through van der Waals forces(2). At very high densities, molecular bonding has long been predicted to give way to a monatomic and presumably metallic lattice(3). At intermediate densities, intermolecular interactions are expected to increase; however, the relative strengths of the intermolecular and intramolecular interactions, and their effect on physical and chemical properties, have received comparatively little attention theoretically. Recent diamond-anvil-cell studies have revealed a range of unexpected phenomena in solid hydrogen at these densities(4). Here we show that marked changes in the infrared and Raman spectra of the intramolecular stretching modes (vibrons)(5) with increasing pressure can be interpreted in a manner analogous to the behaviour of organic charge-transfer salts at ambient pressure, including those exhibiting pressure-induced neutral-to-ionic transitions(6,7) Increased molecular overlap in dense hydrogen leads to symmetry breaking, which makes possible charge-transfer states between adjacent H-2 molecules. The consequent changes in bond strength and in vibron frequencies are evident in the spectra. These findings present a new picture of dense hydrogen and highlight the advantages of a localized, 'chemical' description of the bonding.
C1 CARNEGIE INST WASHINGTON, CTR HIGH PRESSURE RES, WASHINGTON, DC 20015 USA.
   PRINCETON UNIV, DEPT CHEM, PRINCETON, NJ 08544 USA.
C3 Carnegie Institution for Science; Princeton University
RP HEMLEY, RJ (corresponding author), CARNEGIE INST WASHINGTON, GEOPHYS LAB, WASHINGTON, DC 20015 USA.
NR 39
TC 68
Z9 76
U1 2
U2 20
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 384
EP 387
DI 10.1038/369384a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400051
DA 2026-03-10
ER

PT J
AU DERMOTT, SF
   JAYARAMAN, S
   XU, YL
   GUSTAFSON, BAS
   LIOU, JC
AF DERMOTT, SF
   JAYARAMAN, S
   XU, YL
   GUSTAFSON, BAS
   LIOU, JC
TI A CIRCUMSOLAR RING OF ASTEROIDAL DUST IN RESONANT LOCK WITH THE EARTH
SO NATURE
LA English
DT Article
ID poynting-robertson drag; orbital resonances; evolution; emission; iras
AB Numerical simulations of the orbital evolution of asteroidal dust particles show that the Earth is embedded in a circumsolar ring of asteroidal dust, and has a cloud of dust permanently in its wake. This could account for the asymmetry of the zodiacal cloud observed by the Infrared Astronomical Satellite (IRAS). The resonant trapping and subsequent release of dust particles by the ring may provide a mechanism by which carbonaceous material is transported from the asteroid belt to the Earth.
RP DERMOTT, SF (corresponding author), UNIV FLORIDA, DEPT ASTRON, POB 112055, GAINESVILLE, FL 32611 USA.
NR 33
TC 208
Z9 220
U1 0
U2 5
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 719
EP 723
DI 10.1038/369719a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100051
DA 2026-03-10
ER

PT J
AU LEWIN, GR
   MCKINTOSH, E
   MCMAHON, SB
AF LEWIN, GR
   MCKINTOSH, E
   MCMAHON, SB
TI NMDA RECEPTORS AND ACTIVITY-DEPENDENT TUNING OF THE RECEPTIVE-FIELDS OF SPINAL-CORD NEURONS
SO NATURE
LA English
DT Article
ID peripheral-nerve injury; rat dorsal horn; sensory map; cat; plasticity; reorganization; regeneration; antagonist; activation; kainate
AB AFTER peripheral nerve section, sensory neurons regenerate but do not regain their original topographical position in the skin(1). Here we report that in the early stages of sciatic nerve regeneration, the cutaneous receptive fields (RFs) of dorsal horn neurons are larger than normal, reflecting the disorganized topography of the regenerated afferents. When nerve regeneration is complete, small contiguous RFs emerge, indicating a central compensation for the disrupted peripheral somatotopy. If the NMDA receptor antagonist MK801 is given during regeneration, RFs do not show this reorganization, but remain large and diffuse. We suggest that the coincident activity of afferents, newly innervating adjacent or overlapping cutaneous territory, acts through postsynaptic NMDA receptors(2) to strengthen the central effectiveness of these inputs at the expense of other non-adjacent and non-coincidently activated inputs. In this way, dorsal horn neurons may attain and retain restricted RFs in the face of a spatially dispersed afferent input.
C1 UNITED MED & DENT SCH GUYS & ST THOMASS HOSP,DEPT PHYSIOL,LONDON SE1 7EH,ENGLAND.
   SUNY STONY BROOK,DEPT NEUROBIOL & BEHAV,STONY BROOK,NY 11794.
C3 University of London; King's College London; State University of New York (SUNY) System; Stony Brook University
NR 29
TC 29
Z9 29
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 482
EP 485
DI 10.1038/369482a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600056
PM 8202138
DA 2026-03-10
ER

PT J
AU CRESPO, P
   XU, NZ
   SIMONDS, WF
   GUTKIND, JS
AF CRESPO, P
   XU, NZ
   SIMONDS, WF
   GUTKIND, JS
TI RAS-DEPENDENT ACTIVATION OF MAP KINASE PATHWAY MEDIATED BY G-PROTEIN BETA-GAMMA-SUBUNITS
SO NATURE
LA English
DT Article
ID nih 3t3 cells; alpha-subunits; receptor; expression; transformation; proliferation; stimulation; fibroblasts; inhibition; signals
AB MITOGEN-ACTIVATED protein kinases, MAP kinases or ERKs (extracellular signal-regulated kinases) are rapidly stimulated by growth-promoting factors acting on a variety of cell-surface receptors (1,2). In turn, ERKs phosphorylate and regulate key intracellular enzymes and transcription factors involved in the control of cellular proliferation(3,4). The tyrosine-kinase class of growth-factor receptors transmits signals to ERKs in a multistep process that involves Ras and a limited number of defined molecules(5). In contrast, ERK activation by G-protein-coupled receptors is poorly understood(3,6), as is the role of ras in this signalling pathway(7,8). We have explored in COS-7 cells the mechanism of ERKs activation by m1 and m2 muscarinic receptors, typical examples of receptors coupled through Gq proteins to induce phosphatidylinositol hydrolysis and to G(i) proteins to inhibit adenylyl cyclase, respectively(9). Here we present evidence that ERK activation is mediated by beta gamma subunits of heterotrimeric G proteins acting on a ras-dependent pathway.
C1 NIDR, CELLULAR DEV & ONCOL LAB, MOLEC SIGNALLING UNIT, BETHESDA, MD 20892 USA.
   NIDDKD, METAB DIS BRANCH, BETHESDA, MD 20892 USA.
C3 National Institutes of Health (NIH) - USA; NIH National Institute of Dental & Craniofacial Research (NIDCR); National Institutes of Health (NIH) - USA; NIH National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK)
NR 30
TC 791
Z9 865
U1 0
U2 12
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 418
EP 420
DI 10.1038/369418a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400062
PM 8196770
DA 2026-03-10
ER

PT J
AU TIESSEN, H
   CUEVAS, E
   CHACON, P
AF TIESSEN, H
   CUEVAS, E
   CHACON, P
TI THE ROLE OF SOIL ORGANIC-MATTER IN SUSTAINING SOIL FERTILITY
SO NATURE
LA English
DT Article
ID nutrient dynamics; forest; radiocarbon; cultivation; succession; rates; c-14
AB MANY tropical soils are poor in inorganic nutrients and rely on the recycling of nutrients from soil organic matter to maintain fertility. In undisturbed rainforests such nutrients are recycled via the litter(1); 'slash-and-burn'agriculture, meanwhile, depends on the mineralization of organic nutrients from the plant remains(2,3) or on (short-lived) inputs from ash(4). This dependence on organic nutrients in tropical soils has the result that tests of soil quality which only give isolated measures of inorganic nutrient status are unreliable(5), and that the effects of fertilization can be inconsistent because of leaching or fixation of inorganic nutrients. Here we attempt to quantify the role of organic matter in sustaining the fertility of soils from three different climate zones. We estimate rates of carbon turnover from ecological measurements and C-14 dating. and determine its relation to the soil carbon and nutrient budgets. We find that agriculture without supplementary fertilization was economical for 65 years on temperate prairie and for sis years in a tropical semi-arid thorn forest. An extremely nutrient-poor Amazonian soil showed no potential for agriculture beyond the three-year lifespan of the forest litter mat, once biological nutrient cycles were interrupted by slash-burning. These observations suggest that quantification of organic-matter cycling may provide an important guide to the agricultural potential of soils.
C1 INST VENEZOLANO INVEST CIENT,CTR ECOL,CARACAS,VENEZUELA.
   UNIV NACL EXPTL SIMON RODRIGUEZ,CARACAS,VENEZUELA.
C3 Venezuelan Institute Science Research
RP TIESSEN, H (corresponding author), UNIV SASKATCHEWAN,DEPT SOIL SCI,SASKATOON S7N 0W0,SK,CANADA.
NR 26
TC 684
Z9 823
U1 7
U2 352
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 783
EP 785
DI 10.1038/371783a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800054
DA 2026-03-10
ER

PT J
AU GOLDWURM, A
   CORDIER, B
   PAUL, J
   BALLET, J
   BOUCHET, L
   ROQUES, JP
   VEDRENNE, G
   MANDROU, P
   SUNYAEV, R
   CHURAZOV, E
   GILFANOV, M
   FINOGENOV, A
   VIKHLININ, A
   DYACHKOV, A
   KHAVENSON, N
   KOVTUNENKO, V
AF GOLDWURM, A
   CORDIER, B
   PAUL, J
   BALLET, J
   BOUCHET, L
   ROQUES, JP
   VEDRENNE, G
   MANDROU, P
   SUNYAEV, R
   CHURAZOV, E
   GILFANOV, M
   FINOGENOV, A
   VIKHLININ, A
   DYACHKOV, A
   KHAVENSON, N
   KOVTUNENKO, V
TI POSSIBLE EVIDENCE AGAINST A MASSIVE BLACK-HOLE AT THE GALACTIC-CENTER
SO NATURE
LA English
DT Article
ID gamma-ray observations; x-ray; sigma; discovery; energy; emission; galaxy
AB THE centre of our Galaxy is known to contain a large condensation of mass(1), and it has been suggested that a massive black hole (of several million solar masses) is located there. Massive black holes have been proposed to explain active galactic nuclei, and if the Galactic Centre is a less-powerful version of such sources it should radiate X-rays and gamma-rays(1). But although earlier observations(2-6) have shown that the region does emit X-rays and gamma-rays, the true centre, corresponding to the object Sagittarius A*, does not emit strongly at least up to energies of 30 keV (refs 4-6). Whether Sgr A* emits radiation at higher energies, however, was not resolved. Here we present the results of a deep imaging survey of the Galactic Centre, performed with the Sigma/GRANAT telescope. We determine the locations of the nine hard X-ray sources-six of them being observed for the first time in the spectral band-to an accuracy of about 2 arcmin, but find no source associated with Sgr A*. The hard X-ray luminosity of Sgr A* is a factor of. 4 x 10(7) less than that expected for a black hole of a million solar masses accreting gas at the maximum stable rate, challenging the idea that there is a black hole at the Galactic Centre.
C1 CTR ETUD SPATIALE RAYONNEMENTS, F-31029 TOULOUSE, FRANCE.
   MOSCOW SPACE RES INST, MOSCOW 117296, RUSSIA.
C3 Universite de Toulouse; Universite Toulouse III - Paul Sabatier; Russian Academy of Sciences; Space Research Institute of the Russian Academy of Sciences
RP GOLDWURM, A (corresponding author), CTR ETUD SACLAY, CEA, DSM, DAPNIA, SERV ASTROPHYS, F-91191 GIF SUR YVETTE, FRANCE.
NR 27
TC 81
Z9 83
U1 0
U2 1
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 589
EP 591
DI 10.1038/371589a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900045
DA 2026-03-10
ER

PT J
AU JAMESON, BA
   MCDONNELL, JM
   MARINI, JC
   KORNGOLD, R
AF JAMESON, BA
   MCDONNELL, JM
   MARINI, JC
   KORNGOLD, R
TI A RATIONALLY DESIGNED CD4 ANALOG INHIBITS EXPERIMENTAL ALLERGIC ENCEPHALOMYELITIS
SO NATURE
LA English
DT Article
ID monoclonal-antibody
AB EXPERIMENTAL allergic encephalomyelitis (EAE) is an acute inflammatory autoimmune disease of the central nervous system that can be elicited in rodents and is the major animal model for the study of multiple sclerosis (MS)(1,2). The pathogenesis of both EAE and MS directly involves the CD4(+) helper T-cell subset(3-5) Anti-CD4 monoclonal antibodies inhibit the development of EAE in rodents(6-9), and are currently being used in human clinical trials for MS. We report here that similar therapeutic effects can be achieved in mice using a small (rationally designed) synthetic analogue of the CD4 protein surface. It greatly inhibits both clinical incidence and severity of EAE with a single injection, but does so without depletion of the CD4(+) subset and without the inherent immunogenicity of an antibody. Furthermore, this analogue is capable of exerting its effects on disease even after the onset of symptoms.
RP JAMESON, BA (corresponding author), THOMAS JEFFERSON UNIV, JEFFERSON CANC INST, PHILADELPHIA, PA 19107 USA.
NR 14
TC 135
Z9 215
U1 0
U2 5
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 744
EP 746
DI 10.1038/368744a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300059
PM 8152486
DA 2026-03-10
ER

PT J
AU FERRONOVICK, S
   JAHN, R
AF FERRONOVICK, S
   JAHN, R
TI VESICLE FUSION FROM YEAST TO MAN
SO NATURE
LA English
DT Article
ID integral membrane-protein; gtp-binding proteins; vesicular transport; neurotransmitter release; endoplasmic-reticulum; secretory pathway; golgi-complex; tetanus toxin; in-vitro; synaptotagmin
AB Membrane budding and fusion occur in all eukaryotic cells. Their underlying mechanisms have been studied in mammalian neurons and in yeast, a simple eukaryote. The differences between these two systems would suggest that fusion events in yeast and the neuron would operate by different mechanisms, but recent advances indicate that this is not true.
C1 YALE UNIV,SCH MED,HOWARD HUGHES MED INST,NEW HAVEN,CT 06510.
C3 Howard Hughes Medical Institute; Yale University
RP FERRONOVICK, S (corresponding author), YALE UNIV,SCH MED,DEPT CELL BIOL & PHARMACOL,NEW HAVEN,CT 06510, USA.
NR 56
TC 593
Z9 636
U1 0
U2 25
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 191
EP 193
DI 10.1038/370191a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100042
PM 8028665
DA 2026-03-10
ER

PT J
AU FARINELLA, P
   FROESCHLE, C
   FROESCHLE, C
   GONCZI, R
   HAHN, G
   MORBIDELLI, A
   VALSECCHI, GB
AF FARINELLA, P
   FROESCHLE, C
   FROESCHLE, C
   GONCZI, R
   HAHN, G
   MORBIDELLI, A
   VALSECCHI, GB
TI ASTEROIDS FALLING INTO THE SUN
SO NATURE
LA English
DT Article
ID secular resonances; taurid complex; state
AB THE orbits of comets and near-Earth asteroids evolve chaotically, mainly in response to the gravitational influence of the planets. For comets, it is known that such perturbations can result in trajectories that either collide with or graze the Sun(1-3). Indeed, it has been calculated(3) that 6% of the known short-period comets (including comet Encke) will become Sun-grazers an a timescale of similar to 10(5) years. But there has been no previous indication that asteroids may suffer a similar fate. To address this question, we have integrated numerically the orbits of several near-Earth asteroids. We find that these asteroids can also undergo solar collisions, through several dynamical routes involving orbital resonances with the giant planets, on timescales of the order of 10(6) years. Of the 47 objects studied, we found 19 cases in which the asteroid collided with the Sun, implying that solar collisions are a more common fate than planetary collisions or ejection from the Solar System. Past Sun-grazing events may also have been recorded in the surface composition and spectral properties of some existing near-Earth asteroids.
C1 OBSERV COTE AZUR,F-06304 NICE 4,FRANCE.
   DLR,INST PLANETENERKUNDUNG,BERLIN,GERMANY.
   CNR,INST ASTROPHYS SPATIALE,REPARTO PLANETOL,ROME,ITALY.
C3 Universite Cote d'Azur; Observatoire de la Cote d'Azur; Helmholtz Association; German Aerospace Centre (DLR); Consiglio Nazionale delle Ricerche (CNR)
RP FARINELLA, P (corresponding author), UNIV PISA,DIPARTIMENTO MATEMAT,I-56100 PISA,ITALY.
NR 20
TC 167
Z9 175
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 314
EP 317
DI 10.1038/371314a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400046
DA 2026-03-10
ER

PT J
AU LAFONT, F
   BURKHARDT, JK
   SIMONS, K
AF LAFONT, F
   BURKHARDT, JK
   SIMONS, K
TI INVOLVEMENT OF MICROTUBULE MOTORS IN BASOLATERAL AND APICAL TRANSPORT IN KIDNEY-CELLS
SO NATURE
LA English
DT Article
ID darby canine kidney; intestinal epithelial-cells; plasma-membrane proteins; mdck cells; cytoplasmic dynein; surface polarity; actin-filaments; caco-2; identification; glycoprotein
AB THE maintenance of a polarized cell surface requires vectorial transport of vesicles to the apical and the basolateral membrane domains(1). Transport of newly synthesized apical proteins and trans-cytosis from the basolateral to the apical surface have Motors been demonstrated to depend on microtubules(2-9). In contrast, movement of membrane proteins to the basolateral surface has been claimed to occur by diffusion and to be microtubule- and actin-independent(2,4,5,7,10-12). We have re-examined the role of microtubules using a recently developed polarized transport assay in permeabilized Madin-Darby canine kidney cells(13,14). Here we report that both apical and basolateral transport is inhibited by nocodazole treatment. Transport to the basolateral surface was inhibited by immunodepletion of cytosolic kinesin. In contrast, apical transport involved both dynein and kinesin. Our data demonstrate that in epithelial cells, microtubule motors are involved in the movement of apical and basolateral vesicles. Moreover, we propose that the differential requirement for microtubule-based motors is related to the microtubule organization.
C1 EUROPEAN MOLEC BIOL LAB, CELL BIOL PROGRAMME, D-69112 HEIDELBERG, GERMANY.
C3 European Molecular Biology Laboratory (EMBL)
NR 30
TC 170
Z9 180
U1 0
U2 5
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 801
EP 803
DI 
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200059
PM 7997271
DA 2026-03-10
ER

PT J
AU NICOLAIDES, NC
   PAPADOPOULOS, N
   LIU, B
   WEI, YF
   CARTER, KC
   RUBEN, SM
   ROSEN, CA
   HASELTINE, WA
   FLEISCHMANN, RD
   FRASER, CM
   ADAMS, MD
   VENTER, JC
   DUNLOP, MG
   HAMILTON, SR
   PETERSEN, GM
   DELACHAPELLE, A
   VOGELSTEIN, B
   KINZLER, KW
AF NICOLAIDES, NC
   PAPADOPOULOS, N
   LIU, B
   WEI, YF
   CARTER, KC
   RUBEN, SM
   ROSEN, CA
   HASELTINE, WA
   FLEISCHMANN, RD
   FRASER, CM
   ADAMS, MD
   VENTER, JC
   DUNLOP, MG
   HAMILTON, SR
   PETERSEN, GM
   DELACHAPELLE, A
   VOGELSTEIN, B
   KINZLER, KW
TI MUTATIONS OF 2 PMS HOMOLOGS IN HEREDITARY NONPOLYPOSIS COLON-CANCER
SO NATURE
LA English
DT Article
ID dna mismatch repair; colorectal-cancer; sequence
AB HEREDITARY nonpolyposis colorectal cancer (HNPCC) is one of man's commonest hereditary diseases(1). Several studies have implicated a defect in DNA mismatch repair in the pathogenesis of this disease(2-8). In particular, hMSH2 and hMLH1 homologues of the bacterial DNA mismatch repair genes mutS and mutL, respectively, were shown to be mutated in a subset of HNPCC cases(9-16). Here we report the nucleotide sequence, chromosome localization and mutational analysis of hPMS1 and hPMS2, two additional homologues of the prokaryotic mutL gene. Both hPMS1 and hPMS2 were found to be mutated in the germline of HNPCC patients. This doubles the number of genes implicated in HNPCC and may help explain the relatively high incidence of this disease.
C1 JOHNS HOPKINS ONCOL CTR,BALTIMORE,MD 21231.
   HUMAN GENOME SCI INC,ROCKVILLE,MD 20850.
   INST GENOM RES,GAITHERSBURG,MD 20878.
   WESTERN GEN HOSP,MRC,HUMAN GENET UNIT,EDINBURGH EH4 2XU,MIDLOTHIAN,SCOTLAND.
   JOHNS HOPKINS UNIV,SCH MED,DEPT PATHOL,BALTIMORE,MD 21205.
   JOHNS HOPKINS UNIV,SCH MED,DEPT ONCOL,BALTIMORE,MD 21205.
   JOHNS HOPKINS UNIV,SCH HYG & PUBL HLTH,DEPT EPIDEMIOL,BALTIMORE,MD 21205.
   UNIV HELSINKI,DEPT MED GENET,SF-00290 HELSINKI,FINLAND.
C3 Johns Hopkins University; Johns Hopkins Medicine; GlaxoSmithKline; Glaxosmithkline USA; Human Genome Sciences Inc; J. Craig Venter Institute; University of Edinburgh; Johns Hopkins University; Johns Hopkins University; Johns Hopkins University; University of Helsinki
NR 29
TC 1420
Z9 1555
U1 0
U2 47
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 75
EP 80
DI 10.1038/371075a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100055
PM 8072530
DA 2026-03-10
ER

PT J
AU PRICE, R
   COHEN, S
AF PRICE, R
   COHEN, S
TI A MORAL QUESTION FOR PATENT LEGISLATION .1.
SO NATURE
LA English
DT Article
AB In considering the grounds on which to award patents for applications of germline gene therapy, the European Patent Office may have to decide on the basis of ''morality''. This should not be its job.
RP PRICE, R (corresponding author), TAYLOR JOYNSON GARRETT,LONDON EC4Y 0DX,ENGLAND.
NR 0
TC 1
Z9 1
U1 1
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 589
EP 589
DI 10.1038/369589a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400059
PM 8202163
DA 2026-03-10
ER

PT J
AU SANCHEZ, I
   HUGHES, RT
   MAYER, BJ
   YEE, K
   WOODGETT, JR
   AVRUCH, J
   KYRIAKIS, JM
   ZON, LI
AF SANCHEZ, I
   HUGHES, RT
   MAYER, BJ
   YEE, K
   WOODGETT, JR
   AVRUCH, J
   KYRIAKIS, JM
   ZON, LI
TI ROLE OF SAPK/ERK KINASE-1 IN THE STRESS-ACTIVATED PATHWAY REGULATING TRANSCRIPTION FACTOR C-JUN
SO NATURE
LA English
DT Article
ID map kinase; protein-kinase; phosphorylation; expression; tyrosine; cloning; family; mek
AB THE stress-activated protein kinases (SAPKs), which are distantly related to the MAP kinases, are the dominant c-Jun amino-terminal protein kinases activated in response to a variety of cellular stresses, including treatment with tumour-necrosis factor-a and interleukin-beta (refs 1, 2). SAPK phosphorylation of c-Jun probably activates the c-Jun transactivation function(3). SAPKs are part of a signal transduction cascade related to, but distinct from, the MAPK pathway(1). We have now identified a novel protein kinase, called SAPK/ERK kinase-1 (SEK1), which is structurally related to the MAP kinase kinases (MEKs)(4). SEK1 is a potent activator of the SAPKs in vitro and in vivo. An inactive SEK1 mutant blocks SAPK activation by extracellular stimuli without interfering with the MAPK pathway. Although alternative mechanisms of SAPK activation may exist, as an immediate upstream activator of the SAPKs, SEK1 further defines a signalling cascade that couples cellular stress agonists to the c-Jun transcription factor.
C1 HARVARD UNIV, SCH MED, DEPT MED, BOSTON, MA 02129 USA.
   HARVARD UNIV, CHILDRENS HOSP, SCH MED, DIV HEMATOL ONCOL, BOSTON, MA 02115 USA.
   HARVARD UNIV, CHILDRENS HOSP, SCH MED, DEPT MICROBIOL & MOLEC GENET, BOSTON, MA 02115 USA.
   HARVARD UNIV, CHILDRENS HOSP, SCH MED, HOWARD HUGHES MED INST, BOSTON, MA 02115 USA.
   HARVARD UNIV, CHILDRENS HOSP, SCH MED, DANA FARBER CANC INST, BOSTON, MA 02115 USA.
   PRINCESS MARGARET HOSP, ONTARIO CANC INST, TORONTO M4X 1K9, ON, CANADA.
C3 Harvard University; Harvard Medical School; Harvard University; Harvard Medical School; Harvard University Medical Affiliates; Boston Children's Hospital; Harvard University; Harvard University Medical Affiliates; Boston Children's Hospital; Harvard Medical School; Harvard University; Harvard Medical School; Harvard University Medical Affiliates; Boston Children's Hospital; Howard Hughes Medical Institute; Harvard University; Harvard University Medical Affiliates; Dana-Farber Cancer Institute; Harvard Medical School; Boston Children's Hospital; University of Toronto; University Health Network Toronto; Princess Margaret Cancer Centre
RP SANCHEZ, I (corresponding author), MASSACHUSETTS GEN HOSP E, MED SERV, DIABET RES LAB, 149 13TH ST, BOSTON, MA 02129 USA.
NR 28
TC 969
Z9 1025
U1 0
U2 6
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 794
EP 798
DI 
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200057
PM 7997269
DA 2026-03-10
ER

PT J
AU MASLOV, DA
   AVILA, HA
   LAKE, JA
   SIMPSON, L
AF MASLOV, DA
   AVILA, HA
   LAKE, JA
   SIMPSON, L
TI EVOLUTION OF RNA EDITING IN KINETOPLASTID PROTOZOA
SO NATURE
LA English
DT Article
ID trypanosoma-brucei; guide rnas; crithidia-fasciculata; subunit; gene; mitochondria; transcript; domains; region; dna
AB THE editing of RNA in trypanosomatid mitochondria involves the insertion and occasional deletion of uridine residues within coding regions of maxicircle messenger RNA transcripts. The extent to which the transcripts of homologous genes undergo editing differs in different species. In some, entire genes are edited (pan-editing), whereas in others, editing is limited to the 5' termini of editing domains (5' editing)(1,2). Here we investigate which type of editing is ancestral and which is derived, by analysing RNA editing in the different lineages, using a kinetoplastid phylogeny reconstructed from nuclear small subunit ribosomal RNA sequences. We conclude that the ancestral cryptogenes were pan-edited, and we hypothesize that the 5'-edited homologues were generated by several independent events from partially edited RNAs, in which case editing may be a more primitive mechanism than previously thought.
C1 UNIV CALIF LOS ANGELES, DEPT BIOL, LOS ANGELES, CA 90024 USA.
   UNIV CALIF LOS ANGELES, INST MOLEC BIOL, LOS ANGELES, CA 90024 USA.
   UNIV CALIF LOS ANGELES, HOWARD HUGHES MED INST, LOS ANGELES, CA 90024 USA.
C3 University of California System; University of California Los Angeles; University of California System; University of California Los Angeles; Howard Hughes Medical Institute; University of California System; University of California Los Angeles
NR 36
TC 135
Z9 139
U1 0
U2 9
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 345
EP 348
DI 10.1038/368345a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500049
PM 8127370
DA 2026-03-10
ER

PT J
AU MURAKAMI, M
   AMII, H
   ITO, Y
AF MURAKAMI, M
   AMII, H
   ITO, Y
TI SELECTIVE ACTIVATION OF CARBON-CARBON BONDS NEXT TO A CARBONYL GROUP
SO NATURE
LA English
DT Article
ID c-c; cleavage; olefins; complex; ketones
AB ORGANOMETALLIC complexes are used to effect a wide range of catalytic transformations in organic synthesis, such as the activation of C-H bonds(1,2). Carbon-carbon bonds, however, are generally unreactive towards transition metals under homogeneous conditions. C-C bond activation by a process of oxidative addition to soluble transition-metal complexes has been limited mostly to stoichiometric (not catalytic) reactions(1,3-7,18), to highly strained substrates such as cyclopropane and cubane(1,8-11) or to chelating ketones(19). Here we present a synthetically useful process of selective C-C bond activation in which the C-C bond adjacent to a carbonyl group is opened by insertion of a soluble rhodium(I) complex. The resulting organometallic intermediate can be transformed to a variety of products in a way that regenerates the rhodium complex. We anticipate that this catalytic scheme will have considerable utility in organic synthesis.
RP MURAKAMI, M (corresponding author), KYOTO UNIV,FAC ENGN,DEPT SYNTHET CHEM,YOSHIDA,KYOTO 60601,JAPAN.
NR 19
TC 269
Z9 294
U1 3
U2 71
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 540
EP 541
DI 10.1038/370540a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700048
DA 2026-03-10
ER

PT J
AU LINDE, AT
   SACKS, IS
   JOHNSTON, MJS
   HILL, DP
   BILHAM, RG
AF LINDE, AT
   SACKS, IS
   JOHNSTON, MJS
   HILL, DP
   BILHAM, RG
TI INCREASED PRESSURE FROM RISING BUBBLES AS A MECHANISM FOR REMOTELY TRIGGERED SEISMICITY
SO NATURE
LA English
DT Article
ID long-valley caldera; volcanic systems; california
AB AFTERSHOCKS Of large earthquakes tend to occur close to the main rupture zone, and can be used to constrain its dimensions. But following the 1992 Landers earthquake (magnitude M(w)= 7.3) in southern California,many aftershocks were reported(1) in areas remote from the mainshock. Intriguingly, this remote seismicity occurred in small clusters near active volcanic and geothermal systems. For one of these clusters (Long Valley, about 400 km from the Landers earthquake), crustal deformation associated with the seismic activity was also monitored, Here we argue that advective overpressure(2-7) provides a viable mechanism for remote seismicity triggered by the Landers earthquake. Both the deformation and seismicity data are consistent with pressure increases owing to gas bubbles rising slowly within a volume of magma. These bubbles may have been shaken loose during the passage of seismic waves generated by the mainshock.
C1 US GEOL SURVEY,MENLO PK,CA 94025.
   UNIV COLORADO,DEPT GEOL SCI,BOULDER,CO 80309.
C3 United States Department of the Interior; United States Geological Survey; University of Colorado System; University of Colorado Boulder
RP LINDE, AT (corresponding author), CARNEGIE INST WASHINGTON,DEPT TERR MAGNETISM,5241 BROAD BRANCH RD NW,WASHINGTON,DC 20015, USA.
NR 20
TC 110
Z9 117
U1 1
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 408
EP 410
DI 10.1038/371408a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500039
DA 2026-03-10
ER

PT J
AU LEE, KJ
   MCCORMICK, WD
   PEARSON, JE
   SWINNEY, HL
AF LEE, KJ
   MCCORMICK, WD
   PEARSON, JE
   SWINNEY, HL
TI EXPERIMENTAL-OBSERVATION OF SELF-REPLICATING SPOTS IN A REACTION-DIFFUSION SYSTEM
SO NATURE
LA English
DT Article
AB IN his classic 1952 paper, Turing(1) suggested a possible connection between patterns in biological systems and patterns that could form spontaneously in chemical reaction-diffusion systems. Turing's analysis stimulated considerable theoretical research on mathematical models of pattern formation, but Turing-type patterns were not observed in controlled laboratory experiments until 1990(2,3). Subsequently there has been a renewed interest in chemical pattern formation and in the relationship of chemical patterns to the remarkably similar patterns observed in diverse physical and biological systems(4). Numerical simulations of a simple model chemical system have recently revealed spot patterns that undergo a continuous process of 'birth' through replication and 'death' through overcrowding(5). Here we report the observation of a similar phenomenon in laboratory experiments on the ferrocyanide-iodate-sulphite reaction. Repeated growth and replication can be observed for a wide range of experimental parameters, and can be reproduced by a simple two-species model, suggesting that replicating spots may occur in many reaction-diffusion systems.
C1 UNIV TEXAS,DEPT PHYS,AUSTIN,TX 78712.
   LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545.
C3 University of Texas System; University of Texas Austin; United States Department of Energy (DOE); Los Alamos National Laboratory
RP LEE, KJ (corresponding author), UNIV TEXAS,CTR NONLINEAR DYNAM,AUSTIN,TX 78712, USA.
NR 13
TC 430
Z9 440
U1 1
U2 54
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 215
EP 218
DI 10.1038/369215a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700050
DA 2026-03-10
ER

PT J
AU BARTLEY, TD
   HUNT, RW
   WELCHER, AA
   BOYLE, WJ
   PARKER, VP
   LINDBERG, RA
   LU, HS
   COLOMBERO, AM
   ELLIOTT, RL
   GUTHRIE, BA
   HOLST, PL
   SKRINE, JD
   TOSO, RJ
   ZHANG, M
   FERNANDEZ, E
   TRAIL, G
   VARNUM, B
   YARDEN, Y
   HUNTER, T
   FOX, GM
AF BARTLEY, TD
   HUNT, RW
   WELCHER, AA
   BOYLE, WJ
   PARKER, VP
   LINDBERG, RA
   LU, HS
   COLOMBERO, AM
   ELLIOTT, RL
   GUTHRIE, BA
   HOLST, PL
   SKRINE, JD
   TOSO, RJ
   ZHANG, M
   FERNANDEZ, E
   TRAIL, G
   VARNUM, B
   YARDEN, Y
   HUNTER, T
   FOX, GM
TI B61 IS A LIGAND FOR THE ECK RECEPTOR PROTEIN-TYROSINE KINASE
SO NATURE
LA English
DT Article
ID cell
AB A PROTEIN ligand for the ECK1 receptor protein-tyrosine kinase has been isolated by using the extracellular domain (ECK-X) of the receptor as an affinity reagent. Initially, concentrated cell culture supernatants were screened for receptor binding activity using immobilized ECK-X in a surface plasmon resonance detection system2,3. Subsequently, supernatants from selected cell lines were fractionated directly by receptor affinity chromatography, resulting in the single-step purification of B61, a protein previously identified as the product of an early response gene induced by tumour necrosis factor-alpha4. We report here that recombinant B61 induces autophosphorylation of ECK in intact cells, consistent with B61 being an authentic ligand for ECK. ECK is a member of a large orphan receptor protein-tyrosine kinase family headed by EPH5, and we suggest that ligands for other members of this family will be related to B61, and can be isolated in the same way.
C1 WEIZMANN INST SCI, DEPT CLIN IMMUNOL, IL-76100 REHOVOT, ISRAEL.
   SALK INST BIOL STUDIES, MOLEC BIOL & VIROL LAB, SAN DIEGO, CA 92186 USA.
C3 Weizmann Institute of Science; Salk Institute
RP BARTLEY, TD (corresponding author), AMGEN INC, AMGEN CTR, THOUSAND OAKS, CA 91320 USA.
NR 17
TC 232
Z9 270
U1 0
U2 8
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 558
EP 560
DI 10.1038/368558a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500058
PM 8139691
DA 2026-03-10
ER

PT J
AU JAKOBSEN, P
   BOKSENBERG, A
   DEHARVENG, JM
   GREENFIELD, P
   JEDRZEJEWSKI, R
   PARESCE, F
AF JAKOBSEN, P
   BOKSENBERG, A
   DEHARVENG, JM
   GREENFIELD, P
   JEDRZEJEWSKI, R
   PARESCE, F
TI DETECTION OF INTERGALACTIC IONIZED HELIUM ABSORPTION IN A HIGH-REDSHIFT QUASAR
SO NATURE
LA English
DT Article
ID lyman-limit absorption; he-i absorption; alpha clouds; spectra; forest; lines; photoionization; evolution; continuum; hydrogen
AB Observations obtained with the recently refurbished Hubble Space Telescope reveal strong absorption arising from singly ionized helium along the line of sight to a high-redshift quasar. The strength of the absorption suggests that it may arise in a diffuse ionized intergalactic medium. The detection also confirms that substantial amounts of helium existed in the early Universe, as predicted by Big Bang nucleosyntheis theory.
C1 ROYAL GREENWICH OBSERV,CAMBRIDGE CB3 0EZ,ENGLAND.
   CNRS,ASTRON SPATIALE LAB,F-13012 MARSEILLE,FRANCE.
   SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218.
C3 University of Cambridge; Centre National de la Recherche Scientifique (CNRS); Space Telescope Science Institute
RP JAKOBSEN, P (corresponding author), EUROPEAN SPACE TECHNOL CTR,EUROPEAN SPACE AGCY,DEPT SPACE SCI,DIV ASTROPHYS,2200 AG NOORDWIJK,NETHERLANDS.
NR 37
TC 197
Z9 203
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 35
EP 39
DI 10.1038/370035a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100049
DA 2026-03-10
ER

PT J
AU WANG, TC
   CARDIFF, RD
   ZUKERBERG, L
   LEES, E
   ARNOLD, A
   SCHMIDT, EV
AF WANG, TC
   CARDIFF, RD
   ZUKERBERG, L
   LEES, E
   ARNOLD, A
   SCHMIDT, EV
TI MAMMARY HYPERPLASIA AND CARCINOMA IN MMTV-CYCLIN D1 TRANSGENIC MICE
SO NATURE
LA English
DT Article
ID cell-cycle; mouse strain; oncogene; protein; expression; gene; int-2; chromosome-11q13; overexpression; abnormality
AB Physical associations between cyclins, viral oncogenes and tumour suppressor genes imply a central role for cyclins in growth control(1,2). Cyclin D1 was identified as a candidate oncogene (PRAD1) in tumour-specific DNA rearrangements(3,4) and is suspected to be a contributor to several types of neoplasms including breast cancer(5,6). Cyclin D1 also rescues G1 cyclin-defective Saccharomyces cerevisiae(7), and is a growth-regulated genes. Despite evidence suggesting that cyclin D1 is an oncogene, its ability to transform cells directly in culture remains controversial(9-16). To evaluate its potential to deregulate growth in vivo in a physiologically relevant tissue we overexpressed cyclin D1 in mammary cells in transgenic mice. We report here that overexpression of cyclin D1 resulted in abnormal mammary cell proliferation including the development of mammary adenocarcinomas. We conclude that overexpression of cyclin D1 deregulates cell proliferation and can induce tumorigenic changes in mammary tissues, suggesting that cyclin D1 indeed plays an important oncogenic role in breast cancer.
C1 MASSACHUSETTS GEN HOSP, CTR CANC, BOSTON, MA 02129 USA.
   UNIV CALIF DAVIS, SCH MED, DEPT PATHOL, DAVIS, CA 95616 USA.
   MASSACHUSETTS GEN HOSP, DEPT MED, ENDOCRINE ONCOL LAB, BOSTON, MA 02114 USA.
   MASSACHUSETTS GEN HOSP, CTR CANC, BOSTON, MA 02114 USA.
   MASSACHUSETTS GEN HOSP, DEPT PATHOL, BOSTON, MA 02114 USA.
   MASSACHUSETTS GEN HOSP, CHILDRENS SERV, BOSTON, MA 02129 USA.
   MASSACHUSETTS GEN HOSP, DEPT MED, GASTROINTESTINAL UNIT, BOSTON, MA 02114 USA.
C3 Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; University of California System; University of California Davis; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital
NR 25
TC 900
Z9 994
U1 0
U2 18
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 669
EP 671
DI 10.1038/369669a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900061
PM 8208295
DA 2026-03-10
ER

PT J
AU KOMBIAN, SB
   MALENKA, RC
AF KOMBIAN, SB
   MALENKA, RC
TI SIMULTANEOUS LTP OF NON-NMDA-RECEPTER-MEDIATED AND LTD OF NMDA-RECEPTER-MEDIATED RESPONSES IN THE NUCLEUS-ACCUMBENS
SO NATURE
LA English
DT Article
ID long-term depression; molecular mechanisms; membrane-property; neurons invitro; area ca1; rat; hippocampus; potentials; aspartate; dopamine
AB THE nucleus accumbens (NA), a ventral extension of the striatum, plays a role in several complex behaviour patterns(1) and also is a major site of action of drugs of abuse such as cocaine(1-3). Intrinsic NA cells are predominantly quiescent(4,5) and their activity depends on excitatory input from cortical and subcortical limbic afferents(6,7). Here we examine the mechanisms of synaptic plasticity at the synapse between prelimbic cortical afferents and cells in the core region of the NA(8-10). Manipulations that induce a Ca2+- dependent long-term potentiation (LTP) of non-NMDA (N-methyl-D-aspartate)-receptor-mediated responses also produce a simultaneous long-term depression (LTD) of NMDA-receptor-mediated responses. These results indicate that in a single cell the same change in postsynaptic Ca2+ concentration can have opposite effects on non-NMDA- and NMDA-receptor-mediated synaptic responses. This may be particularly important in the NA, where NMDA receptors are critical for mediating the behavioural actions of drugs of abuse(11-13).
C1 UNIV CALIF SAN FRANCISCO,DEPT PSYCHIAT,LPPI,SAN FRANCISCO,CA 94143.
   UNIV CALIF SAN FRANCISCO,DEPT PHYSIOL,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco; University of California System; University of California San Francisco
NR 30
TC 177
Z9 202
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 242
EP 246
DI 10.1038/368242a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000055
PM 7908412
DA 2026-03-10
ER

PT J
AU ZHANG, JF
   ELLINOR, PT
   ALDRICH, RW
   TSIEN, RW
AF ZHANG, JF
   ELLINOR, PT
   ALDRICH, RW
   TSIEN, RW
TI MOLECULAR DETERMINANTS OF VOLTAGE-DEPENDENT INACTIVATION IN CALCIUM CHANNELS
SO NATURE
LA English
DT Article
ID functional expression; sodium-channel; k+ channels; periodic paralysis; ion channels; cells; mechanisms; kinetics; blockade; antibody
AB VOLTAGE-DEPENDENT Ca2+ channels respond to membrane depolarization by conformational changes that control channel opening and eventual closing by inactivation(1-3). The kinetics of inactivation differ considerably between types of Ca2+ channels(1-8) and are important in determining the amount of Ca2+ entry during electrical activity and its resulting impact on diverse cellular events(3). The most intensively characterized forms of inactivation in potassium(9,10) and sodium channels(11-13) involve pore block by a tethered plug(14). In contrast, little is known about the molecular basis of Ca2+-channel inactivation. We studied the molecular mechanism of inactivation of voltage-gated calcium channels by making chimaeras from channels with different inactivation rates. We report here that the amino acids responsible for the kinetic differences are localized to membrane-spanning segment S6 of the first repeat of the alpha(1) subunit (IS6), and to putative extracellular and cytoplasmic domains flanking IS6. Involvement of this region in Ca2+-channel inactivation was unexpected and raises interesting comparisons with Na+ channels, where the III-IV loop is a critical structural determinant. Ca2+-channel inactivation has some features that resemble C-type inactivation of potassium channels.
C1 STANFORD UNIV,MED CTR,HOWARD HUGHES MED INST,DEPT MOLEC & CELLULAR PHYSIOL,STANFORD,CA 94305.
C3 Stanford University; Howard Hughes Medical Institute
NR 31
TC 184
Z9 206
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 97
EP 100
DI 10.1038/372097a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800081
PM 7969428
DA 2026-03-10
ER

PT J
AU JOOSTEN, MHAJ
   COZIJNSEN, TJ
   DEWIT, PJGM
AF JOOSTEN, MHAJ
   COZIJNSEN, TJ
   DEWIT, PJGM
TI HOST-RESISTANCE TO A FUNGAL TOMATO PATHOGEN LOST BY A SINGLE BASE-PAIR CHANGE IN AN AVIRULENCE GENE
SO NATURE
LA English
DT Article
ID bacterial spot disease; syringae pv glycinea; cladosporium-fulvum; race; proteins; avr9
AB HOST genotype specificity in interactions between biotrophic pathogens and plants in most cases complies with the gene-for-gene model1; success or failure of infection is determined by absence or presence of complementary genes, avirulence and resistance genes, in the pathogen and host plant, respectively. Resistance, expressed by the induction of a hypersensitive response in the host, is envisaged to be based on recognition of the pathogen, mediated through direct interaction between products of pathogen avirulence genes (the so-called race-specific elicitors) and receptors in the host plant, the putative products of resistance genes1. The interaction between the biotrophic fungus Cladosporium fulvum and its only host, tomato (Lycopersicon esculentum), is a well-established model system for studying fungus-plant gene-for-gene relationships1. Here we report the isolation of race-specific elicitor AVR4 of C. fulvum and the cloning of its encoding avirulence gene. We present evidence that, in nature, a single base-pair change in this avirulence gene leads to virulence of races previously avirulent on tomato genotypes carrying the complementary Cf4 resistance gene.
C1 WAGENINGEN UNIV AGR,DEPT PHYTOPATHOL,POB 8025,6700 EE WAGENINGEN,NETHERLANDS.
C3 Wageningen University & Research
NR 13
TC 317
Z9 382
U1 1
U2 40
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 384
EP 386
DI 10.1038/367384a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000073
PM 8114941
DA 2026-03-10
ER

PT J
AU LONSDALE, CJ
   DIAMOND, PJ
   SMITH, HE
   LONSDALE, CJ
AF LONSDALE, CJ
   DIAMOND, PJ
   SMITH, HE
   LONSDALE, CJ
TI COMPACT OH-MEGAMASER AND PROBABLE QUASAR ACTIVITY IN THE GALAXY ARP-220
SO NATURE
LA English
DT Article
ID ultraluminous infrared galaxy; molecular clouds; ic-4553; starburst; emission; nucleus; arp-220; origin
AB ARP 220 is the prototype far-infrared ultraluminous galaxy, and the origin of its luminosity-a burst of massive star formation or a quasar obscured by a layer of dense gas and dust-has been the subject of much debate(1,2) It also contains the prototypical OH megamaser(3)-an extremely luminous version of masers (microwave lasers) commonly found in our own galaxy. It has been thought that the dense gas in the inner few hundred parsecs of megamaser galaxies acts as a low-gain masing screen, pumped by the far-infrared radiation, which amplifies background continuum emission from the nuclear regions(4-6). Here we show, using new very-long-baseline interferometry observations, that the OH line peak in Arp 220 originates in a structure less than or equal to 1 pc across, positionally aligned with a weak continuum feature, and that most of the emission originates on scales of less than or equal to 10 pc. These results imply that the maser is physically 10-100 times smaller than previously thought(5,6), strongly suggesting that much of the far-infrared radiation from Arp 220 arises in a very small region, possibly a dense molecular torus, surrounding a quasar nucleus.
C1 NATL RADIO ASTRON OBSERV,SOCORRO,NM 87801.
   UNIV CALIF SAN DIEGO,CTR ASTROPHYS & SPACE SCI,LA JOLLA,CA 92093.
   UNIV CALIF SAN DIEGO,DEPT PHYS,LA JOLLA,CA 92093.
   CALTECH,CTR INFRARED PROC & ANAL,PASADENA,CA 91125.
   CALTECH,JET PROP LAB,PASADENA,CA 91125.
C3 National Radio Astronomy Observatory (NRAO); University of California System; University of California San Diego; University of California System; University of California San Diego; California Institute of Technology; National Aeronautics & Space Administration (NASA); NASA Jet Propulsion Laboratory (JPL); California Institute of Technology
RP LONSDALE, CJ (corresponding author), MIT,HAYSTACK OBSERV,OFF ROUTE 40,WESTFORD,MA 01886, USA.
NR 23
TC 38
Z9 39
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 117
EP 120
DI 10.1038/370117a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400048
DA 2026-03-10
ER

PT J
AU ANDERS, MH
AF ANDERS, MH
TI CONSTRAINTS ON NORTH-AMERICAN PLATE VELOCITY FROM THE YELLOWSTONE HOTSPOT DEFORMATION FIELD
SO NATURE
LA English
DT Article
ID snake river plain; flood basalts; quaternary; mantle; motions; plumes; tracks; idaho; basin; rift
AB OCEANIC hotspot tracks generally indicate that the mantle plumes that give rise to them are fixed in position (relative to a lower-mantle reference frame) for timespans of similar to 100 Myr(1-3). It has not been clear whether continental hotspots are equally stable; for example, there is evidence that the velocity of the Yellowstone hotspot has been quite irregular with respect to the North American plate over the past 16 Myr(4-7), but measurements of its velocity based on caldera locations have been too uncertain and irregular to be definitive. Here I describe a new method of obtaining the plume velocity, which uses the broader lithospheric effects of the hotspot rather than the locations of individual calderas. For the past 10 Myr, the results indicate a constant North American plate velocity of 2.2 cm yr(-1), which agrees with independent estimates from global plate motion inversions(8,9). This velocity is considerably lower than previous estimates obtained from caldera locations, and clearly differs from the much higher (but less well constrained) velocities of the previous 6 Myr (refs 5, 7).
C1 COLUMBIA UNIV,DEPT GEOL SCI,PALISADES,NY 10964.
C3 Columbia University
RP ANDERS, MH (corresponding author), COLUMBIA UNIV,LAMONT DOHERTY EARTH OBSERV,PALISADES,NY 10964, USA.
NR 27
TC 27
Z9 35
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 53
EP 55
DI 10.1038/369053a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000050
DA 2026-03-10
ER

PT J
AU CONRAD, B
   WEIDMANN, E
   TRUCCO, G
   RUDERT, WA
   BEHBOO, R
   RICORDI, C
   RODRIQUEZRILO, H
   FINEGOLD, D
   TRUCCO, M
AF CONRAD, B
   WEIDMANN, E
   TRUCCO, G
   RUDERT, WA
   BEHBOO, R
   RICORDI, C
   RODRIQUEZRILO, H
   FINEGOLD, D
   TRUCCO, M
TI EVIDENCE FOR SUPERANTIGEN INVOLVEMENT IN INSULIN-DEPENDENT DIABETES-MELLITUS ETIOLOGY
SO NATURE
LA English
DT Article
ID glutamic-acid decarboxylase; polymerase chain-reaction; renal graft-survival; mammary-tumor virus; molecular compatibility; t-cells; islets; usage; mice; mls
AB INSULIN-DEPENDENT diabetes mellitus (IDDM) is a T-cell-mediated autoimmune disease whose onset is believed to be triggered by unknown environmental factors acting on a predisposing genetic background. Islet-infiltrating T (IIT) cells from two IDDM patients, who had died at the onset of the disease from brain swelling as a complication of ketoacidosis, were analysed. The results provided evidence for the involvement of a pancreatic islet cell membrane-bound superantigen(1,2) as a diabetes aetiopathogenetic factor. There was a selective expansion of a T-cell receptor (TCR) variable segment of the beta-chain (V beta 7) in these IIT cells in association with unselected V alpha-chain segments; extensive junctional diversity of the TCR V beta 7 chains; and evidence of positive selection, after exposure to diabetic islet cell membrane preparations, of V beta 7(+) T-cell clones among peripheral blood lymphocytes from non-diabetic individuals.
C1 CHILDRENS HOSP PITTSBURGH,RANGOS RES CTR,DEPT PEDIAT,DIV IMMUNOGENET,PITTSBURGH,PA 15213.
   UNIV PITTSBURGH,SCH MED,DEPT PATHOL,PITTSBURGH,PA 15213.
   UNIV PITTSBURGH,SCH MED,DEPT SURG,PITTSBURGH,PA 15213.
C3 Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh
NR 26
TC 302
Z9 320
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 351
EP 355
DI 10.1038/371351a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400058
PM 8090207
DA 2026-03-10
ER

PT J
AU SNOW, JE
   HART, SR
   DICK, HJB
AF SNOW, JE
   HART, SR
   DICK, HJB
TI ND AND SR ISOTOPE EVIDENCE LINKING MID-OCEAN-RIDGE BASALTS AND ABYSSAL PERIDOTITES
SO NATURE
LA English
DT Article
ID southwest indian ridge; atlantic ridge; upper mantle; geochemistry; petrogenesis; lavas
AB PERIDOTITES found on the sea floor are widely believed to be residues left by mid-ocean-ridge basalt (MORB) melting. As such, their composition should provide insights into the nature of the sub-oceanic depleted mantle. But although these abyssal peridotites occur in mid-ocean ridge fracture zones(1,2), there is little other evidence in support of their genetic link with MORB, and doubts about it have been raised(3-5). Radiogenic isotopes should be able to provide a powerful test of the hypothesis, but previous studies(3,8-10) on whole rocks have not provided unambiguous answers as they are generally altered by sea water. Here we present measurements of the Nd and Sr isotope compositions of a suite of abyssal peridotite clinopyroxenes which should have resisted alteration. Despite residual seawater contamination of Sr in the clinopyroxenes, the data demonstrate that the peridotites are from a depleted mantle source, identical to that of MORB. This provides a strong indication that abyssal peridotites are residues of MORB melting.
RP SNOW, JE (corresponding author), WOODS HOLE OCEANOG INST,WOODS HOLE,MA 02543, USA.
NR 30
TC 115
Z9 126
U1 0
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 57
EP 60
DI 10.1038/371057a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100048
DA 2026-03-10
ER

PT J
AU UHLIN, U
   EKLUND, H
AF UHLIN, U
   EKLUND, H
TI STRUCTURE OF RIBONUCLEOTIDE REDUCTASE PROTEIN R1
SO NATURE
LA English
DT Article
ID escherichia-coli; lactobacillus-leichmannii; diphosphate reductase; subunit interaction; barrel enzymes; inhibition; refinement; mutant; site; r2
AB Ribonucleotide reductase is the only enzyme that catalyses de novo formation of deoxyribonucleotides and is thus a key enzyme in DNA synthesis. The radical-based reaction involves five cysteines. Two redox-active cysteines are located at adjacent antiparallel strands in a new type of ten-stranded alpha/beta-barrel, and two others at the carboxyl end in a flexible arm. The fifth cysteine, in a loop in the centre of the barrel, is positioned to initiate the radical reaction.
RP UHLIN, U (corresponding author), SWEDISH UNIV AGR SCI, UPPSALA BIOMED CTR, DEPT MOLEC BIOL, BOX 590, S-75124 UPPSALA, SWEDEN.
NR 47
TC 526
Z9 602
U1 0
U2 48
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 533
EP 539
DI 10.1038/370533a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700047
PM 8052308
DA 2026-03-10
ER

PT J
AU LOPEZ, GA
   JAN, YN
   JAN, LY
AF LOPEZ, GA
   JAN, YN
   JAN, LY
TI EVIDENCE THAT THE S6 SEGMENT OF THE SHAKER VOLTAGE-GATED K+ CHANNEL COMPRISES PART OF THE PORE
SO NATURE
LA English
DT Article
ID potassium channels; sodium-channels; giant-axons; barium ions; inactivation; block; drosophila; mutations; receptor; region
AB POTASSIUM channels are highly selective and allow the rapid flux of potassium ions through their pore1. Several studies have implicated the H5 (P or SS1-SS2) segment2,3 as part of the pore in voltage-gated ion channels4-10. The proposal that H5 spans at least 80% of the electric potential drop across the K+ channel pore5,11 is based on altered internal tetraethylammonium sensitivity arising from mutations of H5 residues that are 100% conserved among K+ channels having differing sensitivity to tetraethylammonium5-7,12,13. Here we report that the S6 segment is also involved in K+ ion permeation and in governing the sensitivity to internal tetraethylammonium and barium. Transplanting the S6 segment of NGK2 into Shaker causes this S6 chimaera to adopt the single-channel conductance and sensitivity to internal tetraethylammonium and barium ions from the NGK2 channel. The differences between NGK2 and Shaker in external tetraethylammonium sensitivity, but not single-channel conductance, can be attributed to the differences in their H5 sequences. Three non-conserved S6 residues have been found to affect either single-channel conductance or internal tetraethylammonium sensitivity.
C1 UNIV CALIF SAN FRANCISCO,DEPT PHYSIOL,SAN FRANCISCO,CA 94143.
   UNIV CALIF SAN FRANCISCO,DEPT BIOCHEM,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco; University of California System; University of California San Francisco
RP LOPEZ, GA (corresponding author), UNIV CALIF SAN FRANCISCO,HOWARD HUGHES MED INST,PARNASSUS & 3RD AVE,U-426,SAN FRANCISCO,CA 94143, USA.
NR 30
TC 163
Z9 174
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 179
EP 182
DI 10.1038/367179a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000063
PM 8114915
DA 2026-03-10
ER

PT J
AU LIEBERMAN, DN
   MODY, I
AF LIEBERMAN, DN
   MODY, I
TI REGULATION OF NMDA CHANNEL FUNCTION BY ENDOGENOUS CA2+-DEPENDENT PHOSPHATASE
SO NATURE
LA English
DT Article
ID d-aspartate receptors; okadaic acid; protein phosphatase; central neurons; rat-brain; calcineurin; activation; glutamate; dephosphorylation; hippocampus
AB PROTEIN kinases modulate the activity of several ligand-gated ion channels(1), including the NMDA (N-methyl-D-aspartate)(2) subtype of glutamate receptor. Although phosphorylation and dephosphorylation of glutamate receptors may participate in several lasting physiological and pathological alterations of neuronal excitability(3-7), the physiological control of this cycle for NMDA channels has not yet been established. Using cell-attached recordings in acutely dissociated adult rat dentate gyrus granule cells, we now demonstrate that inhibitors of an endogenous serine/threonine phosphatase prolong the duration of single NMDA channel openings, bursts, clusters and superclusters. Okadaic acid, a non-selective phosphatase inhibitor, prolongs channel openings only at a concentration that inhibits the Ca2+/calmodulin-dependent phosphatase 2B (calcineurin)(8), and is ineffective when Ca2+ entry through NMDA channels is prevented. Furthermore, FK506, an inhibitor of calcineurin(9,10), mimics the effects of okadaic acid. Thus in adult neurons, calcineurin, activated by calcium entry through native NMDA channels, shortens the duration of channel openings. Simulated synaptic currents(11) were enhanced after phosphatase inhibition, which is consistent with the importance of phosphorylation of the NMDA-receptor complex in the short- and longterm control of neuronal excitability.
C1 UNIV TEXAS,SW MED CTR,DEPT ANESTESIOL & PAIN MANAGEMENT,DALLAS,TX 75235.
   STANFORD UNIV,SCH MED,GRAD PROGRAM NEUROSCI,STANFORD,CA 94305.
C3 University of Texas System; University of Texas Southwestern Medical Center; University of Texas Dallas; Stanford University
NR 30
TC 431
Z9 471
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 235
EP 239
DI 10.1038/369235a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700057
PM 7514273
DA 2026-03-10
ER

PT J
AU MORRIS, P
   SHAMAN, J
   ATTAYA, M
   AMAYA, M
   GOODMAN, S
   BERGMAN, C
   MONACO, JJ
   MELLINS, E
AF MORRIS, P
   SHAMAN, J
   ATTAYA, M
   AMAYA, M
   GOODMAN, S
   BERGMAN, C
   MONACO, JJ
   MELLINS, E
TI AN ESSENTIAL ROLE FOR HLA-DM IN ANTIGEN PRESENTATION BY CLASS-II MAJOR HISTOCOMPATIBILITY MOLECULES
SO NATURE
LA English
DT Article
ID invariant chain peptides; processing mutant; dr molecules; binding-site; cell line; complex; region; gene; expression; responses
AB IN antigen-presenting cells, class II molecules of the major histocompatibility complex (MHC) bind peptides derived from endocytosed proteins1. In certain B-lymphoblastoid cell mutants, MHC class II molecule-peptide complex formation is impaired, resulting in deficient antigen-presenting function2. MHC deletion mutants with this defect map the responsible gene(s) to the class II region of the MHC3-5. Here we report that multiple independent mutants with the class II presentation defect harbour lesions in HLA-DMB, an MHC-linked gene encoding a class II-like beta-chain6,7. Expression of DMB complementary DNA in mutants lacking DMB messenger RNA restores the wild-type phenotype. These results establish HLA-DM as a critical regulatory molecule in class II-restricted antigen presentation and suggest that it functions at an intracellular site to promote class II molecule-peptide association.
C1 UNIV PENN,DEPT PEDIAT,PHILADELPHIA,PA 19104.
   VIRGINIA COMMONWEALTH UNIV,MED COLL VIRGINIA,DEPT MICROBIOL & IMMUNOL,RICHMOND,VA 23298.
C3 University of Pennsylvania; Virginia Commonwealth University
NR 29
TC 367
Z9 396
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 551
EP 554
DI 10.1038/368551a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500056
PM 8139689
DA 2026-03-10
ER

PT J
AU TIEMEI, C
   QUAN, Y
   EN, W
AF TIEMEI, C
   QUAN, Y
   EN, W
TI ANTIQUITY OF HOMO-SAPIENS IN CHINA
SO NATURE
LA English
DT Article
ID esr
AB TEN years ago a well-preserved skull of an early form of Home sapiens was unearthed from Pleistocene cave deposits at the Jinniushan site in China. Here we present electron-spin resonance (ESR) and uranium-series dates from five fossil animal teeth collected from the hominid locality. The minimum ESR ages (195-165 kyr) are about 50 kyr younger than the uranium-series dates. Taken together, the results suggest an age of about 200 kyr or older for the Jinniushan skull, making it among the oldest H. sapiens material found in China, and almost as old as some of the latest Chinese H. erectus. This raises the possibility of the coexistence of the two species in China. The morphology of the skull suggests a strong local component of evolution, consonant with the 'multiregional continuity' model of the evolution of H. sapiens.
C1 BEIJING UNIV,DEPT PHYS,BEIJING 100871,PEOPLES R CHINA.
C3 Peking University
RP TIEMEI, C (corresponding author), BEIJING UNIV,DEPT ARCHAEOL,BEIJING 100871,PEOPLES R CHINA.
NR 11
TC 29
Z9 38
U1 3
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 55
EP 56
DI 10.1038/368055a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900050
PM 8107882
DA 2026-03-10
ER

PT J
AU IWASHITA, Y
   KAWAGUCHI, S
   MURATA, M
AF IWASHITA, Y
   KAWAGUCHI, S
   MURATA, M
TI RESTORATION OF FUNCTION BY REPLACEMENT OF SPINAL-CORD SEGMENTS IN THE RAT
SO NATURE
LA English
DT Article
ID central nervous-system; axonal regeneration; corticospinal tract; plasticity; transplantation; transection; mechanisms; projection; recovery; guidance
AB RECONSTRUCTiON Of 2 Severed mammalian spinal cord with restoration of function has so far not been achieved1-12, although structural and functional restitution after spinal transection has been successful in some lower vertebrates12-14. In quail hick nd chick chick chimaeras, spinal cord segments were found to be functional after replacement by isotopic and isochronic grafting of the neural tube15,16. Here we achieve such a replacement in neonatal rats under less restricted topological and temporal conditions than were necessary for the avian chimaeras. The replaced segments united with the host spinal cord and promoted robust growth and regrowth of axons across the graft, enabling neural connections to be reconstructed that were hardly distinguishable from normal. The animals with replaced segments could walk, run and climb with almost normal hind-forelimb coordination. This functional restoration in these animals appeared to be permanent, raising the possibility of therapeutic application in humans.
C1 KYOTO UNIV, FAC MED, DEPT ORTHOPAED SURG, KYOTO 606, JAPAN.
C3 Kyoto University
RP IWASHITA, Y (corresponding author), KYOTO UNIV, FAC MED, DEPT INTEGRAT BRAIN SCI, KYOTO 606, JAPAN.
NR 30
TC 200
Z9 210
U1 0
U2 6
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 167
EP 170
DI 10.1038/367167a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000059
PM 8114911
DA 2026-03-10
ER

PT J
AU CHEN, XS
   SHELLER, JR
   JOHNSON, EN
   FUNK, CD
AF CHEN, XS
   SHELLER, JR
   JOHNSON, EN
   FUNK, CD
TI ROLE OF LEUKOTRIENES REVEALED BY TARGETED DISRUPTION OF THE 5-LIPOXYGENASE GENE
SO NATURE
LA English
DT Article
ID platelet-activating-factor; mouse ear edema; mast-cells; mice; stimulation; peritonitis; modulation; mediators; products; invitro
AB LEUKOTRIENES constitute a class of potent biological mediators of inflammation and anaphylaxis (for reviews see refs 1 and 2). Their biosynthesis derives from 5-lipoxygenase-catalysed oxygenation of arachidonic acid in granulocytes, macrophages and mast cells. To examine the physiological importance of leukotrienes, we have disrupted the 5-lipoxygenase gene by homologous recombination in embryonic stem cells. 5-Lipoxygenase-deficient (5LX(-/-)) mice develop normally and are healthy. They show a selective opposition to certain inflammatory insults. Although there is no difference in their reaction to endotoxin shock, the 5LX(-/-) animals resist the lethal effects of shock induced by platelet-activating factor. Reaction to ear inflammation induced by phorbol ester is normal, whereas inflammation induced by arachidonic acid is markedly reduced. Contrasts mere also found in two models of leukocyte chemotaxis in vivo. The phenotype of 5LX(-/-) mice under injurious insult identifies the role for leukotrienes in the pathophysiology of select inflammatory states.
C1 VANDERBILT UNIV,DEPT PHARMACOL,NASHVILLE,TN 37232.
   VANDERBILT UNIV,DEPT MED,NASHVILLE,TN 37232.
C3 Vanderbilt University; Vanderbilt University
NR 28
TC 343
Z9 373
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 179
EP 182
DI 10.1038/372179a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800056
PM 7969451
DA 2026-03-10
ER

PT J
AU HATTORI, M
   ADACHI, H
   TSUJIMOTO, M
   ARAI, H
   INOUE, K
AF HATTORI, M
   ADACHI, H
   TSUJIMOTO, M
   ARAI, H
   INOUE, K
TI MILLER-DIEKER LISSENCEPHALY GENE ENCODES A SUBUNIT OF BRAIN PLATELET-ACTIVATING-FACTOR
SO NATURE
LA English
DT Article
ID factor acetylhydrolase; factor paf; chromosome-17p13; purification; receptor; repeats; clones; pcr
AB PLATELET-ACTIVATING factor (PAF) is involved in a variety of biological and pathological processes(1) and PAF acetylhydrolase, which inactivates PAF by removing the acetyl group at the sn-2 position, is widely distributed in plasma and tissue cytosols(2,3). One isoform of PAP acetylhydrolase present in bovine brain cortex is a heterotrimer comprising subunits with relative molecular masses of 45K, 30K and 29K (ref. 4). We have now isolated the complementary DNA for the 45K subunit. Sequence analysis revealed a striking identity (99%) of the subunit with a protein encoded by the causative gene (LIS-1) for MiUer-Dieker lissencephaly(5), a human brain malformation manifested by a smooth cerebral surface and abnormal neuronal migration. This indicates that the LIS-1 gene product is a human homologue of the 45K subunit of intracellular PAF acetylhydrolase. Our results raise the possibility that PAF and PAF acetylhydrolase are important in the formation of the brain cortex during differentiation and development.
C1 SUNTORY INST BIOMED RES,MISHIMA 618,OSAKA,JAPAN.
C3 Suntory Holdings Ltd
RP HATTORI, M (corresponding author), UNIV TOKYO,FAC PHARMACEUT SCI,DEPT HLTH CHEM,BUNKYO KU,TOKYO 113,JAPAN.
NR 18
TC 438
Z9 476
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 216
EP 218
DI 10.1038/370216a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100052
PM 8028668
DA 2026-03-10
ER

PT J
AU SMITH, RD
   CHENG, X
   BRUCE, JE
   HOFSTADLER, SA
   ANDERSON, GA
AF SMITH, RD
   CHENG, X
   BRUCE, JE
   HOFSTADLER, SA
   ANDERSON, GA
TI TRAPPING, DETECTION AND REACTION OF VERY LARGE SINGLE MOLECULAR-IONS BY MASS-SPECTROMETRY
SO NATURE
LA English
DT Article
ID electrospray ionization
AB RECENT developments have made electrospray-ionization (ESI) mass spectrometry(1-3) an important technique for measuring molecular weights and studying the structures of large molecules of relative molecular masses approaching 200,000 (M(r) 200K). Analysis of still larger molecules is difficult, however: to obtain a mass/charge ratio within the detectable limits, the ions must bear several charges, but a collection of ions of differing multiple charges presents a Spectrum that is hard to interpret. This problem would be avoided if sufficient sensitivity can be achieved to detect individual molecules. Here we describe a technique that realizes this sensitivity for molecules of M(r) to similar to 7 x 10(6), and which has the potential to be extended to M(r) approximate to 10(9). We use ESI and Fourier-transform ion cyclotron resonance mass spectrometry(4) to obtain repeated measurements of the mass-to-charge ratio of single, highly charged molecular ions. We are able to observe stepwise changes in the charge of an isolated ion owing to its reaction with small molecules introduced into the detection cell. This technique should have wide applications for characterization of polymers and large biomolecules.
RP SMITH, RD (corresponding author), PACIFIC NW LAB, DEPT CHEM SCI, RICHLAND, WA 99352 USA.
NR 13
TC 127
Z9 149
U1 0
U2 27
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 137
EP 139
DI 10.1038/369137a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100045
DA 2026-03-10
ER

PT J
AU CHUNG, H
   CAFFREY, M
AF CHUNG, H
   CAFFREY, M
TI THE CURVATURE ELASTIC-ENERGY FUNCTION OF THE LIPID-WATER CUBIC MESOPHASE
SO NATURE
LA English
DT Article
ID x-ray-diffraction; membrane-lipids; phases; lamellar; transitions; systems; crystals; surface
AB CELL and lipid membranes are able to bend, as manifested during membrane fusion and the formation of non-lamellar lyotropic mesophases in water. But there is an energy cost to bending of lipid layers, called the curvature elastic energy. Although the functional form of this energy is known(1), a complete quantitative knowledge of the curvature elastic energy, which is central to predicting the relative stability of the large number of phases that lipid membranes can adopt, has been lacking. Here we use X-ray synchrotron diffraction measurements of the variation of lattice parameter with pressure and temperature for the periodic Ia3d (Q(230)) cubic phase of hydrated monoolein to calculate the complete curvature elastic-energy function for the lipid cubic mesophase. This allows us to predict the stabilities of different cubic and lamellar phases for this system as a function of composition.
RP CHUNG, H (corresponding author), OHIO STATE UNIV,DEPT CHEM,COLUMBUS,OH 43210, USA.
NR 24
TC 112
Z9 117
U1 0
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 224
EP 226
DI 10.1038/368224a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000048
PM 8145820
DA 2026-03-10
ER

PT J
AU HAIGH, JD
AF HAIGH, JD
TI THE ROLE OF STRATOSPHERIC OZONE IN MODULATING THE SOLAR RADIATIVE FORCING OF CLIMATE
SO NATURE
LA English
DT Article
ID northern-hemisphere winter; irradiance variations; ultraviolet irradiance; middle atmosphere; circulation model; global climate; cycle; temperature; qbo; variability
AB MANY recent studies have reported an apparent correlation between solar activity and the Earth's climate on the timescale of the ii-year solar cycle(1-4) and over longer periods(5-10), but to date no physical mechanism has been proposed that can satisfactorily explain the observations. In general, it has been assumed that changes in total solar irradiance outside the atmosphere will be reflected in proportionately equal changes at the tropopause (from where the influence on climate is determined). Here I present results from a two-dimensional radiative-chemical-transport model which show that the spectral composition of the solar variations and the photochemical production of stratospheric ozone together lead to a highly nonlinear relationship between the extraterrestrial and cross-tropopause solar radiative flux. Because of this relationship, at middle to high latitudes in the winter hemisphere less solar radiation reaches the troposphere during periods of higher solar activity. The consequent change in latitudinal temperature gradient also affects infrared radiative forcing and potentially planetary-wave activity. The general mechanism proposed here may explain some features of the observed correlations between solar variability and climate.
RP HAIGH, JD (corresponding author), UNIV LONDON IMPERIAL COLL SCI & TECHNOL,BLACKETT LAB,SPACE & ATMOSPHER PHYS GRP,LONDON SW7 2BZ,ENGLAND.
NR 31
TC 343
Z9 373
U1 0
U2 40
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 544
EP 546
DI 10.1038/370544a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700050
DA 2026-03-10
ER

PT J
AU WILSON, KP
   BLACK, JAF
   THOMSON, JA
   KIM, EE
   GRIFFITH, JP
   NAVIA, MA
   MURCKO, MA
   CHAMBERS, SP
   ALDAPE, RA
   RAYBUCK, SA
   LIVINGSTON, DJ
AF WILSON, KP
   BLACK, JAF
   THOMSON, JA
   KIM, EE
   GRIFFITH, JP
   NAVIA, MA
   MURCKO, MA
   CHAMBERS, SP
   ALDAPE, RA
   RAYBUCK, SA
   LIVINGSTON, DJ
TI STRUCTURE AND MECHANISM OF INTERLEUKIN-1-BETA CONVERTING-ENZYME
SO NATURE
LA English
DT Article
ID receptor antagonist protein; collagen-induced arthritis; death gene ced-3; cell-death; 3-dimensional structure; molecular-cloning; side-chain; papain; resolution; il-1-beta
AB Interleukin-1 beta converting enzyme (ICE) processes an inactive precursor to the proinflammatory cytokine, Interleukln-1 beta, and may regulate programmed cell death in neuronal cells. The high-resolution structure of human ICE In complex with an inhibitor has been determined by X-ray diffraction. The structure confirms the relationship between human ICE and cell-death proteins in other organisms. The active site spans both the 10 and 20K subunits, which associate to form a tetramer, suggesting a mechanism for ICE autoactivation.
RP WILSON, KP (corresponding author), VERTEX PHARMACEUT INC,40 ALLSTON ST,CAMBRIDGE,MA 02139, USA.
NR 45
TC 757
Z9 885
U1 1
U2 31
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 270
EP 275
DI 10.1038/370270a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900055
PM 8035875
DA 2026-03-10
ER

PT J
AU HARADA, A
   LI, J
   KAMACHI, M
AF HARADA, A
   LI, J
   KAMACHI, M
TI DOUBLE-STRANDED INCLUSION COMPLEXES OF CYCLODEXTRIN THREADED ON POLY(ETHYLENE GLYCOL)
SO NATURE
LA English
DT Article
ID rotaxane; chains
AB MUCH attention has been focused recently on the design and construction of nanoscale structures by supramolecular assembly(1-5). One of the most promising approaches to constructing nanoscale structures is the use of specific interactions between polymers and receptors, as exemplified by biological systems. Recently, polyrotaxanes-complexes in which several cyclic molecules are threaded on the main chains(6-11) or side chains(12) of polymers-have been synthesized with crown ethers or cyclodextrins as the cyclic components. Here we report the self-assembly of double-stranded inclusion complexes of poly(ethylene glycol) with gamma-cyclodextrin, in which two polymer chains are threaded through the macrocycles. These complexes might be useful precursors to more complex supramolecular assemblies such as polycatenanes.
RP HARADA, A (corresponding author), OSAKA UNIV, FAC SCI, DEPT MACROMOLEC SCI, TOYONAKA, OSAKA 560, JAPAN.
NR 14
TC 394
Z9 414
U1 3
U2 137
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 126
EP 128
DI 10.1038/370126a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400051
DA 2026-03-10
ER

PT J
AU SHALLICE, T
   FLETCHER, P
   FRITH, CD
   GRASBY, P
   FRACKOWIAK, RSJ
   DOLAN, RJ
AF SHALLICE, T
   FLETCHER, P
   FRITH, CD
   GRASBY, P
   FRACKOWIAK, RSJ
   DOLAN, RJ
TI BRAIN-REGIONS ASSOCIATED WITH ACQUISITION AND RETRIEVAL OF VERBAL EPISODIC MEMORY
SO NATURE
LA English
DT Article
ID prefrontal cortex; hippocampus; attention; networks; amnesia; humans; pet
AB IT is widely held that conscious recall of past experiences involves a specific system-episodic memory1. Patients with amnesia have gross impairments of episodic memory while other kinds of memory remain intact2,3, suggesting that a separable brain system underlies episodic memory. We have used positron emission tomography (PET) to identify components of this system in normal volunteers. A dual-task interference paradigm4 was used to isolate brain areas associated with acquisition, and a cueing paradigm5 to isolate the areas concerned with retrieval from verbal episodic memory. Acquisition was associated with activity in the left prefrontal cortex and the retrosplenial area, whereas retrieval was associated with activity in right prefrontal cortex and the precuneus. Our results provide clear evidence that episodic memory involves a network of specific prefrontal and posterior structures6,7 which can be fractionated into different component processes.
C1 UCL, DEPT PSYCHOL, GOWER ST, LONDON WC1E 6TB, ENGLAND.
   HAMMERSMITH HOSP, MRC, CYCLOTRON UNIT, LONDON W12 0HS, ENGLAND.
   ROYAL FREE HOSP, SCH MED, LONDON NW3 2QG, ENGLAND.
   NATL HOSP NEUROL & NEUROSURG, LONDON WC1 3BG, ENGLAND.
   INST NEUROL, LONDON WC1N 3BG, ENGLAND.
C3 University of London; University College London; Imperial College London; University of London; University College London; Royal Free London NHS Foundation Trust; UCL Medical School; University of London; University College London; UCL Medical School; University College London Hospitals NHS Foundation Trust; National Hospital for Neurology & Neurosurgery; University of London; University College London
NR 30
TC 738
Z9 803
U1 0
U2 26
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 633
EP 635
DI 10.1038/368633a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200060
PM 8145849
DA 2026-03-10
ER

PT J
AU TOPILKO, P
   SCHNEIDERMAUNOURY, S
   LEVI, G
   BARONVANEVERCOOREN, A
   CHENNOUFI, AB
   SEITANIDOU, T
   BABINET, C
   CHARNAY, P
AF TOPILKO, P
   SCHNEIDERMAUNOURY, S
   LEVI, G
   BARONVANEVERCOOREN, A
   CHENNOUFI, AB
   SEITANIDOU, T
   BABINET, C
   CHARNAY, P
TI KROX-20 CONTROLS MYELINATION IN THE PERIPHERAL NERVOUS-SYSTEM
SO NATURE
LA English
DT Article
ID schwann-cells; basic-protein; po protein; glycoprotein; mouse; gene; expression; mice; molecules; absence
AB THE molecular mechanisms controlling the process of myelination by Schwann cells remain elusive, despite recent progress in the identification and characterization of genes encoding myelin components (reviewed in ref. 1). We have created a null allele in the mouse Krox-20 gene, which encodes a zinc-finger transcription factor(2,3), by in-frame insertion of the Escherichia coli lacZ gene, and have shown that hindbrain segmentation is affected in Krox-20(-/-) embryos(4). We demonstrate here that Krox-20 is also activated in Schwann cells before the onset of myelination and that its disruption blocks Schwann cells at an early stage in their differentiation, thus preventing myelination in the peripheral nervous system. In Krox-20(-/-) mice, Schwann cells wrap their cytoplasmic processes only one and a half turns around the axon, and although they express the early myelin marker, myelin-associated glycoprotein(5), late myelin gene products are absent, including those for protein zero(6) and myelin basic protein(7). Therefore Krox-20 is likely to control a set of genes required for completion of myelination in the peripheral nervous system.
C1 ADV BIOTECHNOL CTR,I-16132 GENOA,ITALY.
   HOP LA PITIE SALPETRIERE,INSERM,U134,F-75651 PARIS 13,FRANCE.
   INST PASTEUR,CNRS,URA 361,F-75724 PARIS 15,FRANCE.
C3 Sorbonne Universite; Institut National de la Sante et de la Recherche Medicale (Inserm); Assistance Publique Hopitaux Paris (APHP); Hopital Universitaire Pitie-Salpetriere - APHP; Pasteur Network; Universite Paris Cite; Institut Pasteur Paris; Centre National de la Recherche Scientifique (CNRS)
RP TOPILKO, P (corresponding author), ECOLE NORMALE SUPER,INSERM,U368,46 RUE ULM,F-75230 PARIS 05,FRANCE.
FU Telethon [94] Funding Source: Medline
NR 24
TC 669
Z9 758
U1 1
U2 22
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 796
EP 799
DI 10.1038/371796a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800059
PM 7935840
DA 2026-03-10
ER

PT J
AU MARENGERE, LEM
   ZHOU, SY
   GISH, GD
   SCHALLER, MD
   PARSONS, JT
   STERN, MJ
   CANTLEY, LC
   PAWSON, T
AF MARENGERE, LEM
   ZHOU, SY
   GISH, GD
   SCHALLER, MD
   PARSONS, JT
   STERN, MJ
   CANTLEY, LC
   PAWSON, T
TI SH2 DOMAIN SPECIFICITY AND ACTIVITY MODIFIED BY A SINGLE RESIDUE
SO NATURE
LA English
DT Article
ID tyrosine-phosphorylated peptides; affinity phosphotyrosyl peptide; growth-factor receptors; signaling gene sem-5; transforming protein; src; binding; grb2; transduction; recognition
AB MANY intracellular targets of protein-tyrosine kinases possess Src homology 2 (SH2) domains that directly recognize phosphotyrosine-containing sites on autophosphorylated growth factor receptors and cytoplasmic proteins, and thereby mediate the activation of biochemical signalling pathways(1-7) SH2 domains possess relatively well conserved residues that form the phosphotyrosine-binding pocket(8-11), and more variable residues that are implicated in determining binding specificity by recognition of the three amino acids carboxy-terminal to phosphotyrosine (the +1 to +3 positions)(5,7,12,13). One such residue, occupying the EF1 position of the +3-binding pocket, is a Thr in the SH2 domain of the Src tyrosine kinase(12), but is predicted to be a Trp in the SH2 domain of the Sem-5/drk/Grb2 adaptor protein(5). Here eve report that changing this residue in the Src SH2 domain from Thr to Trp switches its selectivity to resemble that of the Sem-5-/drk/Grb2 SH2 domain. Furthermore, this mutant Src SH2 domain effectively substitutes for the SH2 domain of the Sem-5 protein in activation of the Ras pathway in vivo. These results identify a residue that can modify SH2 selectivity, and indicate that the biological activity of an SH2 domain correlates with its binding specificity.
C1 UNIV TORONTO, DEPT MOLEC & MED GENET, TORONTO M5S 1A8, ON, CANADA.
   HARVARD UNIV, SCH MED, DEPT CELL BIOL, BOSTON, MA 02115 USA.
   BETH ISRAEL HOSP, DEPT MED, BOSTON, MA 02115 USA.
   UNIV VIRGINIA, DEPT MICROBIOL, CHARLOTTESVILLE, VA 22908 USA.
   UNIV VIRGINIA, CTR CANC, CHARLOTTESVILLE, VA 22908 USA.
   YALE UNIV, BOYER CTR MOLEC MED, NEW HAVEN, CT 06536 USA.
C3 University of Toronto; Harvard University; Harvard Medical School; Harvard University; Harvard University Medical Affiliates; Beth Israel Deaconess Medical Center; University of Virginia; University of Virginia; Yale University
RP MARENGERE, LEM (corresponding author), MT SINAI HOSP, SAMUEL LUNENFELD RES INST, DIV MOLEC & DEV BIOL, 600 UNIV AVE, TORONTO M5G 1X5, ON, CANADA.
NR 31
TC 175
Z9 211
U1 0
U2 12
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 502
EP 505
DI 10.1038/369502a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600062
PM 7515480
DA 2026-03-10
ER

PT J
AU CULLY, DF
   VASSILATIS, DK
   LIU, KK
   PARESS, PS
   VANDERPLOEG, LHT
   SCHAEFFER, JM
   ARENA, JP
AF CULLY, DF
   VASSILATIS, DK
   LIU, KK
   PARESS, PS
   VANDERPLOEG, LHT
   SCHAEFFER, JM
   ARENA, JP
TI CLONING OF AN AVERMECTIN-SENSITIVE GLUTAMATE-GATED CHLORIDE CHANNEL FROM CAENORHABDITIS-ELEGANS
SO NATURE
LA English
DT Article
ID amino-acid receptors; xenopus-oocytes; insect muscle; binding-site; membrane; rna; ivermectin; modulation; expression; fibers
AB THE avermectins are a family of macrocyclic lactones used in the control of nematode and arthropod parasites(1). Ivermectin (22,23-dihydroavermectin B-1a) is widely used as an anthelmintic in veterinary medicine and is used to treat onchocerciasis or river blindness in humans(1,2). Abamectin (avermectin B-1a) is a miticide and insecticide used in crop protection(1). Avermectins interact with vertebrate and invertebrate GABA receptors(3-7) and invertebrate glutamate-gated chloride channels(8-11). The soil nematode Caenorhabditis elegans has served as a useful model to study the mechanism of action of avermectins(11-15). A C. elegans messenger RNA expressed in Xenopus oocytes encodes an avermectin-sensitive glutamate-gated chloride channel(11,14). To elucidate the structure and properties of this channel, we used Xenopus oocytes for expression cloning of two functional complementary DNAs encoding an avermectin-sensitive glutamate-gated chloride channel. We find that the electrophysiological and structural properties of these proteins indicate that they are new members of the ligand-gated ion channel superfamily.
C1 MERCK & CO INC, RES LABS, DEPT GENET & MOLEC BIOL, RAHWAY, NJ 07065 USA.
C3 Merck & Company; Merck & Company USA
RP CULLY, DF (corresponding author), MERCK & CO INC, RES LABS, DEPT CELLULAR BIOCHEM & PHYSIOL, RAHWAY, NJ 07065 USA.
NR 28
TC 630
Z9 743
U1 8
U2 113
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 707
EP 711
DI 10.1038/371707a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300058
PM 7935817
DA 2026-03-10
ER

PT J
AU NEWMAN, M
   STRZELECKA, T
   DORNER, LF
   SCHILDKRAUT, I
   AGGARWAL, AK
AF NEWMAN, M
   STRZELECKA, T
   DORNER, LF
   SCHILDKRAUT, I
   AGGARWAL, AK
TI STRUCTURE OF RESTRICTION-ENDONUCLEASE BAMHI AND ITS RELATIONSHIP TO ECORI
SO NATURE
LA English
DT Article
AB TYPE II restriction endonucleases are characterized by the remarkable specificity with which they cleave specific DNA sequences. Surprisingly, their protein sequences are in most cases unrelated, and no recurring structural motif has yet been identified1,2. We have determined the structure of restriction endonuclease BamHI at 1.95 angstrom resolution. BamHI shows striking resemblance to the structure of endonuclease EcoRI (refs 3, 4), despite the lack of sequence similarity between them. We also observe some curious differences between the two structures, and propose an evolutionary scheme that may explain them. The active site of BamHI is structurally similar to the active sites of EcoRI and EcoRV (ref. 5), but the mechanism by which BamHI activates a water molecule for nucleophilic attack may be different.
C1 COLUMBIA UNIV,DEPT BIOCHEM & MOLEC BIOPHYS,NEW YORK,NY 10032.
   NEW ENGLAND BIOLABS INC,BEVERLY,MA 01915.
C3 Columbia University; New England Biolabs
NR 18
TC 167
Z9 172
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 660
EP 664
DI 10.1038/368660a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200068
PM 8145855
DA 2026-03-10
ER

PT J
AU WIBLE, BA
   TAGLIALATELA, M
   FICKER, E
   BROWN, AM
AF WIBLE, BA
   TAGLIALATELA, M
   FICKER, E
   BROWN, AM
TI GATING OF INWARDLY RECTIFYING K+ CHANNELS LOCALIZED TO A SINGLE NEGATIVELY CHARGED RESIDUE
SO NATURE
LA English
DT Article
ID potassium channel; functional expression; ion channels; rectification; conductance; dependence; blocking; mg-2+; cells
AB INWARDLY rectifying K+ channels (IRKs) conduct current preferentially in the inward direction. This inward rectification has two components: voltage-dependent blockade by intracellular Mg2+ (Mg-i(2+))(1-7) and intrinsic gating(8,9). Two members of this channel family, IRK1 (ref. 10) and ROMK1 (ref. 11), differ markedly in affinity for Mg-i(2+) (ref. 12). We found that IRK1 and ROMK1 differ in voltage-dependent gating and searched for the gating structure by large-scale and site-directed mutagenesis. We found that a single amino-acid change within the putative transmembrane domain M2, aspartate (D) in IRK1 to the corresponding asparagine (N) in ROMK1, controls the gating phenotype. Mutation D172N in IRK1 produced ROMK1-like gating whereas the reverse mutation in ROMK1-N171D-produced IRK1-like gating. Thus, a single negatively charged residue seems to be a crucial determinant of gating.
C1 BAYLOR COLL MED,DEPT MOLEC PHYSIOL & BIOPHYS,HOUSTON,TX 77030.
   UNIV NAPLES FEDERICO II,SCH MED 2,DEPT HUMAN COMMUN SCI,PHARMACOL SECT,I-80121 NAPLES,ITALY.
C3 Baylor College of Medicine; University of Naples Federico II
NR 27
TC 228
Z9 249
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 246
EP 249
DI 10.1038/371246a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000052
PM 8078584
DA 2026-03-10
ER

PT J
AU MURFETT, J
   ATHERTON, TL
   MOU, B
   GASSER, CS
   MCCLURE, BA
AF MURFETT, J
   ATHERTON, TL
   MOU, B
   GASSER, CS
   MCCLURE, BA
TI S-RNASE EXPRESSED IN TRANSGENIC NICOTIANA CAUSES S-ALLELE-SPECIFIC POLLEN REJECTION
SO NATURE
LA English
DT Article
ID self-incompatibility locus; sequence variability; ribonuclease-activity; petunia-inflata; alata; gene; proteins; transformation; brassica; plants
AB MANY angiosperms employ self-incompatibility systems to prevent inbreeding1,2. The simple genetics of such systems3-6 have made them attractive models of plant cellular communication. Implicit in the single locus genetics is that only one or a few gene products are necessary for recognition and rejection of incompatible pollen. Results in the sporophytic system of the Brassicaceae suggest that different S-locus products are responsible for the pollen and pistil parts of the recognition and rejection response7,8. In solanaceous plants, which have a gametophytic self-incompatibility system, the S-locus product responsible for the pollen portion of the interaction has not been identified, but ribonucleases encoded by the S-locus (S-RNases) are strongly implicated in the style part of the recognition and rejection reaction9-14. In Nicotiana alata, pollen r cognition and rejection occur if its S-allele matches either S-allele in the style. The putative stylar S-RNase is abundant in the transmitting tract15, and pollen rejection may be related to action of S-RNaSe on pollen RNAs10.  Efforts to understand the molecular basis for pollen recognition and rejection have been limited by the lack of a system for manipulating and expressing S-RNases4-6,16. Here we use the promoter of a style-expressed gene from tomato to obtain high levels of S-RNase expression in transgenic Nicotiana. Recognition and rejection of N. alata pollen S-alleles occur faithfully in the transgenic plants. Our results show that S-RNases alone are sufficient for pollen rejection in this system.
C1 UNIV MISSOURI,DEPT BIOCHEM,117 SCHWEITZER HALL,COLUMBIA,MO 65211.
   UNIV CALIF DAVIS,MOLEC & CELLULAR BIOL SECT,DAVIS,CA 95616.
C3 University of Missouri System; University of Missouri Columbia; University of California System; University of California Davis
NR 30
TC 324
Z9 373
U1 3
U2 60
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 563
EP 566
DI 10.1038/367563a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300060
PM 8107825
DA 2026-03-10
ER

PT J
AU VANDENBERG, AV
   BRENNER, E
AF VANDENBERG, AV
   BRENNER, E
TI WHY 2 EYES ARE BETTER THAN ONE FOR JUDGMENTS OF HEADING
SO NATURE
LA English
DT Article
ID optical-flow; perception; movements; motion; image
AB ARE two eyes needed for judging direction of self-motion? Traditional analyses stress that the pattern of optic flow in one eye is sufficient(1-5). The main difficulty is how to deal with the eye or head rotation. Extraretinal signals help(6-8), but humans can also discount the effect of rotation purely on the basis of monocular flow(6,7,9-12) provided the scene contains depth(6,9,10). Depth differences give rise to changing binocular disparities when the observer moves. These disparities are ignored in monocular theories of judgements of heading. Using computer generated displays, we investigated whether stereoscopic presentation improves heading judgements for conditions that pose problems to the monocular observer. We found that adding disparities to simulated ego-motion through a cloud of dots made heading judgements up to four times more tolerant to motion noise. The same improvement was found when the disparities specify the initial distances throughout the motion sequence. We conclude that binocular disparities improve judgements of heading by imposing a depth order on the elements of the scene, not because they provide additional information on the elements' motion in depth.
RP VANDENBERG, AV (corresponding author), ERASMUS UNIV ROTTERDAM,FAC MED,POB 1738,3000 DR ROTTERDAM,NETHERLANDS.
NR 12
TC 90
Z9 98
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 700
EP 702
DI 10.1038/371700a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300055
PM 7935814
DA 2026-03-10
ER

PT J
AU HENDRY, PC
   LAWSON, NS
   LEE, RAM
   MCCLINTOCK, PVE
   WILLIAMS, CDH
AF HENDRY, PC
   LAWSON, NS
   LEE, RAM
   MCCLINTOCK, PVE
   WILLIAMS, CDH
TI GENERATION OF DEFECTS IN SUPERFLUID HE-4 AS AN ANALOG OF THE FORMATION OF COSMIC STRINGS
SO NATURE
LA English
DT Article
AB ALTHOUGH the birth of the Universe is inaccessible to experimental study, aspects of cosmological theories can nonetheless be explored in the laboratory. Tiny inhomogeneities in the mix of particles and radiation produced in the Big Bang grew into the clusters of galaxies that,ve see today, but how those inhomogeneities arose and grew is still unclear. Cosmologies based on grand unified theories suggest that a symmetry-breaking phase transition occurred via the Higgs mechanism about 10(-34) s after the Big Bang as the Universe cooled through a critical temperature of 10(27) K. It has been proposed by Kibble(1) that this transition may have generated defects in the geometry of space-time (such as cosmic strings), which provided the inhomogeneities on which galaxies subsequently condensed. Zurek(2-4) has suggested that it might be possible to model this cosmological phase transition by a laboratory analogue, the superfluid transition of liquid He-4 induced by fast adiabatic expansion through the critical density. Here we report the results of such an experiment. We observe copious production of quantized vortices(5), the superfluid analogue of cosmic strings. These results support Kibble's contention that such defects were available in the early Universe to seed galaxy formation.
C1 UNIV EXETER,DEPT PHYS,EXETER EX4 4QL,ENGLAND.
C3 University of Exeter
RP HENDRY, PC (corresponding author), UNIV LANCASTER,SCH PHYS & MAT,LANCASTER LA1 4YB,LANCS,ENGLAND.
NR 13
TC 236
Z9 250
U1 1
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 315
EP 317
DI 10.1038/368315a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500039
DA 2026-03-10
ER

PT J
AU PAUSE, A
   BELSHAM, GJ
   GINGRAS, AC
   DONZE, O
   LIN, TA
   LAWRENCE, JC
   SONENBERG, N
AF PAUSE, A
   BELSHAM, GJ
   GINGRAS, AC
   DONZE, O
   LIN, TA
   LAWRENCE, JC
   SONENBERG, N
TI INSULIN-DEPENDENT STIMULATION OF PROTEIN-SYNTHESIS BY PHOSPHORYLATION OF A REGULATOR OF 5'-CAP FUNCTION
SO NATURE
LA English
DT Article
ID 5' noncoding region; secondary structure; initiation; translation; mechanism; cells; expression; virus
AB The cloning is described of two related human complementary DNAs encoding polypeptides that interact specifically with the translation initiation factor eIF-4E, which binds to the messenger RNA 5'-cap structure. Interaction of these proteins with eIF-4E inhibits translation but treatment of cells with insulin causes one of them to become hyperphosphorylated and dissociate from eIF-4E, thereby relieving the translational inhibition. The action of this new regulator of protein synthesis is therefore modulated by insulin, which acts to stimulate the overall rate of translation and promote cell growth.
C1 MCGILL UNIV,DEPT BIOCHEM,MONTREAL H3G 1Y6,PQ,CANADA.
   MCGILL UNIV,MCGILL CANC CTR,MONTREAL H3G 1Y6,PQ,CANADA.
   BBSRC,INST ANIM HLTH,WOKING GU24 0NF,SURREY,ENGLAND.
   WASHINGTON UNIV,SCH MED,DEPT MOLEC BIOL & PHARMACOL,ST LOUIS,MO 63110.
C3 McGill University; McGill University; UK Research & Innovation (UKRI); Biotechnology and Biological Sciences Research Council (BBSRC); Pirbright Institute; Washington University (WUSTL)
NR 31
TC 1075
Z9 1315
U1 0
U2 34
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 762
EP 767
DI 10.1038/371762a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800049
PM 7935836
DA 2026-03-10
ER

PT J
AU HUGHES, KA
   CHARLESWORTH, B
AF HUGHES, KA
   CHARLESWORTH, B
TI A GENETIC-ANALYSIS OF SENESCENCE IN DROSOPHILA
SO NATURE
LA English
DT Article
ID melanogaster; selection; component; variance
AB Two attractive theories for the evolution of senescence are based on the principle that the force of natural selection decreases with age1-5. The theories differ in the type of age-specific gene action that they assume. Antagonistic pleiotropy2-5 postulates that pleiotropic genes with positive effects early in life and negative effects of comparable magnitude late in life are favoured by selection, whereas genes with the reverse pattern of action are selected against. Mutation accumulation1,3-5 assumes that deleterious mutant alleles with age-specific effects will equilibrate at a lower frequency if their effects are expressed early rather than late in life. Explicit models demonstrate that both mechanisms can lead to the evolution of senescent life histories under reasonable conditions3-5. Antagonistic pleiotropy has gained considerable empirical support4-6, but the evidence in support of mutation accumulation is more sparse4,5,7. Here we report that the genetic variability of mortality in male Drosophila melanogaster increases greatly at very late ages, as predicted by the mutation accumulation hypothesis3-5. The rate of increase in mortality with age exhibits substantial genetic and environmental variability. This result provides a possible explanation for recent observations of non-increasing mortality rates in very old flies8,9.
C1 UNIV CHICAGO, COMM EVOLUT BIOL, CHICAGO, IL 60637 USA.
   UNIV CHICAGO, DEPT ECOL & EVOLUT, CHICAGO, IL 60637 USA.
C3 University of Chicago; University of Chicago
NR 25
TC 148
Z9 160
U1 0
U2 16
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 64
EP 66
DI 10.1038/367064a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500059
PM 8107775
DA 2026-03-10
ER

PT J
AU JOSHI, MM
   LEWIS, SR
   READ, PL
   CATLING, DC
AF JOSHI, MM
   LEWIS, SR
   READ, PL
   CATLING, DC
TI WESTERN BOUNDARY CURRENTS IN THE ATMOSPHERE OF MARS
SO NATURE
LA English
DT Article
ID surface
AB WESTERN boundary currents (WBCs) are an intensification of north-south flow adjacent to an eastward-facing meridional boundary. Although most familiar in the oceans (where the Gulf Stream is the best known example), WBCs also occur in the Earth's troposphere, the main example being the East African Jet1, which is thought to play an important role in the Asiatic monsoon. Here we identify boundary currents in a different geophysical context: a numerical simulation of the atmosphere of Mars. In our simulation, WBCs exist in association with significant cross-equatorial flow and the presence of equatorial martian topography, which has vertical scale far exceeding terrestrial relief2. The intensity and width of these currents depend on model parameters, notably the surface drag. From a comparison of our results with other martian models we suggest that WBCs have already been simulated, although they were not previously identified as such3. The available observational evidence appears to be consistent with the presence of martian WBCs, which may be important in the generation of global and great dust storms.
RP JOSHI, MM (corresponding author), UNIV OXFORD,CLARENDON LAB,PARKS RD,OXFORD,ENGLAND.
NR 22
TC 26
Z9 27
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 548
EP 551
DI 10.1038/367548a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300055
DA 2026-03-10
ER

PT J
AU PHAM, EK
   CHANG, SG
AF PHAM, EK
   CHANG, SG
TI REMOVAL OF NO FROM FLUE-GASES BY ABSORPTION TO AN IRON(II) THIOCHELATE COMPLEX AND SUBSEQUENT REDUCTION TO AMMONIA
SO NATURE
LA English
DT Article
ID desulfurization; denitrification; cysteine
AB THE combustion of fossil fuels generates SO2 and NOx pollutants which cause acid rain and urban smog(1). Existing flue-gas desulphurization scrubbers involve wet limestone processes which are efficient for controlling SO2 emissions but are incapable of removing water-insoluble nitric oxide. The current technique for postcombustion control of nitrogen oxide emissions, ammonia-based selective catalytic reduction, suffers from various problems(2,3), including poisoning of the catalysts by fly ash rich in arsenic or alkali, disposal of spent toxic catalysts and the effects of ammonia by-products on plant components downstream from the reactor. To circumvent the need for separate schemes to control SO2 and NOx, we have developed an iron(II) thiochelate complex that enhances the solubility of NO in aqueous solution by rapidly and efficiently absorbing NO to form iron nitrosyl complexes. The bound NO is then converted to ammonia by electrochemical reduction, regenerating the active iron(II) catalyst for continued NO capture. Our results suggest that this process can be readily integrated into existing wet limestone scrubbers for the simultaneous removal of SO2 and NOx.
RP PHAM, EK (corresponding author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,BERKELEY,CA 94720, USA.
NR 21
TC 124
Z9 144
U1 1
U2 90
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 139
EP 141
DI 10.1038/369139a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100046
DA 2026-03-10
ER

PT J
AU MILLAUER, B
   SHAWVER, LK
   PLATE, KH
   RISAU, W
   ULLRICH, A
AF MILLAUER, B
   SHAWVER, LK
   PLATE, KH
   RISAU, W
   ULLRICH, A
TI GLIOBLASTOMA GROWTH INHIBITED IN-VIVO BY A DOMINANT-NEGATIVE FLK-1 MUTANT
SO NATURE
LA English
DT Article
ID retroviral vectors; angiogenesis; receptor; expression
AB ANGIOGENESIS, the sprouting of capillaries from pre-existing blood vessels, is a fundamental process in the formation of the vascular system during embryonic development. In adulthood, angiogenesis takes place during corpus luteum formation and in pathological conditions such as wound healing, diabetic retinopathy, and tumorigenesis. Vascularization is essential for solid tumour growth and is thought to be regulated by tumour cell-produced factors, which have a chemotactic and mitogenic effect on endothelial cells1-4. Vascular endothelial growth factor (VEGF), a homodimeric glycoprotein of relative molecular mass 45,000, is the only mitogen, however, that specifically acts on endothelial cells, and it may be a major regulator of tumour angiogeness in vivo5,6. Its expression has been shown to be upregulated by hypoxia, and its cell-surface receptor, Flk-1, is exclusively expressed in endothelial cells7,8. Here we investigate the biological relevance of the VEGF/Flk-1 receptor/ligand system for angiogenesis using a retrovirus encoding a dominant-negative mutant of the Flk-1/VEGF receptor to infect endothelial target cells in vivo, and find that tumour growth is prevented in nude mice. Our results emphasize the central role of the Flk-1 /VEGF system in angiogenesis in general and in the development of solid tumours in particular.
C1 MAX PLANCK INST BIOCHEM,DEPT MOLEC BIOL,KLOPFERSPITZ 18A,D-82152 MARTINSRIED,GERMANY.
   SUGEN INC,REDWOOD CITY,CA 94063.
   MAX PLANCK INST PHYSIOL & CLIN RES,WG KERCKHOFF INST,DEPT MOLEC CELL BIOL,D-61231 BAD NAUHEIM,GERMANY.
C3 Max Planck Society; Max Planck Society
NR 19
TC 1129
Z9 1268
U1 0
U2 34
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 576
EP 579
DI 10.1038/367576a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300064
PM 8107827
DA 2026-03-10
ER

PT J
AU COLLETT, TS
   BARON, J
AF COLLETT, TS
   BARON, J
TI BIOLOGICAL COMPASSES AND THE COORDINATE FRAME OF LANDMARK MEMORIES IN HONEYBEES
SO NATURE
LA English
DT Article
ID field; bees
AB MANY hymenopterans use visual landmarks to guide the last stages of their return to a familiar place, moving so that the pattern of landmarks imaged on their retina matches the pattern stored on previous visits to that place(1,2). What is the coordinate frame of these landmark memories, and how is it established? On the one hand, bees and flies learn complex visual shapes retinotopically(3,4), and landmark memories probably share this characteristic. On the other hand, bees record the position of landmarks in compass coordinates. Thus, Lindauer(5) showed that bees that had been trained to feed at the southernmost corner of a square table recognized the corner by its compass bearing from the table's centre. Taken together, these results suggest that these insects place retinotopically localized memories in Earth-based coordinates. We report here that honeybees accomplish this very simply: when learning about or searching for a goal, they face consistently in one compass direction, aided by the Earth's magnetic field. We suggest that the main benefit of inspecting the world from one favoured direction is to simplify the storage and retrieval of retinotopic memories.
RP COLLETT, TS (corresponding author), UNIV SUSSEX, SCH BIOL SCI, SUSSEX CTR NEUROSCI, BRIGHTON BN1 9QG, ENGLAND.
NR 21
TC 132
Z9 142
U1 0
U2 20
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 137
EP 140
DI 10.1038/368137a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000063
DA 2026-03-10
ER

PT J
AU WAGNER, MJ
   HUANG, RH
   EGLIN, JL
   DYE, JL
AF WAGNER, MJ
   HUANG, RH
   EGLIN, JL
   DYE, JL
TI AN ELECTRIDE WITH A LARGE 6-ELECTRON RING
SO NATURE
LA English
DT Article
ID salts
AB ELECTRIDES are crystalline salts that contain complexed alkali metal cations whose charge is balanced by trapped electrons(1). Theory(2,3) and experiment(4,5) indicate that the excess electron distribution is concentrated in cavities and channels formed by close-packing of the large complexed cations. Thus electrides might serve as models of a confined electron gas. Only three electrides have been structurally characterized previously(6-8). Here we report the structure of a new electride, [Cs+(15C5) (18C6).e(-)](6).(18C6), where 15C5 and 18C6 represent crown ethers with five and six oxygen atoms respectively. The unit cell has threefold symmetry, with a central 18C6 molecule surrounded by six Cs+ cations, each sandwiched between a 15C5 and 18C6 molecule. The six electrons released from-the Cs/crown ether interaction seem to be trapped in six cavities which form a puckered ring, three above and three below the plane of the central 18C6 molecule. The ground state is diamagnetic. This ring-like distribution of electrons contrasts with the chain-like connections between electron cavities observed in other electrides(6-8). Polycrystalline samples of this new electride have an electrical conductivity about a million times greater than those of the electrides Cs+(15C5)(2).e(-) and Cs+(18C6)(2).e(-). The size, shape and connectivity of the electron-containing cavities and channels evidently exert a critical influence on the properties of electrides.
C1 MICHIGAN STATE UNIV,DEPT CHEM,E LANSING,MI 48824.
   MICHIGAN STATE UNIV,CTR FUNDAMENTAL MAT RES,E LANSING,MI 48824.
C3 Michigan State University; Michigan State University
NR 15
TC 70
Z9 73
U1 2
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 726
EP 729
DI 10.1038/368726a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300053
DA 2026-03-10
ER

PT J
AU CARMELIET, P
   SCHOONJANS, L
   KIECKENS, L
   REAM, B
   DEGEN, J
   BRONSON, R
   DEVOS, R
   VANDENOORD, JJ
   COLLEN, D
   MULLIGAN, RC
AF CARMELIET, P
   SCHOONJANS, L
   KIECKENS, L
   REAM, B
   DEGEN, J
   BRONSON, R
   DEVOS, R
   VANDENOORD, JJ
   COLLEN, D
   MULLIGAN, RC
TI PHYSIOLOGICAL CONSEQUENCES OF LOSS OF PLASMINOGEN-ACTIVATOR GENE-FUNCTION IN MICE
SO NATURE
LA English
DT Article
ID urokinase-type; messenger-rna; tissue; mouse; localization; inhibitor; fibrinolysis; degradation; trophoblast; mechanisms
AB Indirect evidence suggests a crucial role for the fibrinolytic system and its physiological triggers, tissue-type (t-PA) and urokinase-type (u-PA) plasminogen activator, in many proteolytic processes. Inactivation of the t-PA gene impairs clot lysis and inactivation of the u-PA gene results in occasional fibrin deposition. Mice with combined t-PA and u-PA deficiency suffer extensive spontaneous fibrin deposition, with its associated effects on growth, fertility and survival.
C1 CATHOLIC UNIV LEUVEN, CTR MOLEC & VASC BIOL, B-3000 LOUVAIN, BELGIUM.
   MIT, WHITEHEAD INST BIOMED RES, CAMBRIDGE, MA 02142 USA.
   MIT, DEPT BIOL, CAMBRIDGE, MA 02142 USA.
   UNIV CINCINNATI, CHILDRENS HOSP RES FDN, CINCINNATI, OH 45229 USA.
   TUFTS UNIV, SCH VET MED, BOSTON, MA 02111 USA.
   CATHOLIC UNIV LEUVEN, HISTO & CYTOCHEM LAB, B-3000 LOUVAIN, BELGIUM.
C3 KU Leuven; Massachusetts Institute of Technology (MIT); Whitehead Institute; Massachusetts Institute of Technology (MIT); Cincinnati Children's Hospital Medical Center; Cincinnati Children's Hospital Research Foundation; University System of Ohio; University of Cincinnati; Tufts University; KU Leuven
NR 38
TC 935
Z9 993
U1 0
U2 25
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 419
EP 424
DI 10.1038/368419a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000052
PM 8133887
DA 2026-03-10
ER

PT J
AU CABANA, G
   RASMUSSEN, JB
AF CABANA, G
   RASMUSSEN, JB
TI MODELING FOOD-CHAIN STRUCTURE AND CONTAMINANT BIOACCUMULATION USING STABLE NITROGEN ISOTOPES
SO NATURE
LA English
DT Article
ID trophic level; lake trout; delta-c-13; delta-n-15; carbon; n-15; fish
AB THE nitrogen pools of animals are enriched in N-15 relative to their food(1), with the top predators having the highest concentrations of this stable isotope(2). The use of delta(15) N to indicate trophic position depends on the degree to which it reflects variation in the underlying food-web structure, rather than variable fractionation along the food chain. Here we compare adult lake trout, a top pelagic predator, from a series of lakes, and find that delta(15)N values vary from 7.5 to 17.5 parts per thousand, a surprisingly wide range for one species. The length of the food chain can explain this variation, supporting the idea that delta(15)N is a food-web descriptor. Food-chain length was measured by the presence or absence of two intermediate trophic levels, pelagic forage fish and the macrozooplankter, Mysis relicta, each of which when present contributes about three delta(15)N units to the trout signature. We find that delta(15)N can be used as a continuous, integrative measure of trophic position, which is supported by its correlation to mercury levels in lake trout.
RP CABANA, G (corresponding author), MCGILL UNIV,DEPT BIOL,1205 AVE DOCTEUR PENFIELD,MONTREAL H3A 1B1,PQ,CANADA.
NR 28
TC 711
Z9 822
U1 1
U2 264
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 255
EP 257
DI 10.1038/372255a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900047
DA 2026-03-10
ER

PT J
AU TAYLOR, KE
   PENNER, JE
AF TAYLOR, KE
   PENNER, JE
TI RESPONSE OF THE CLIMATE SYSTEM TO ATMOSPHERIC AEROSOLS AND GREENHOUSE GASES
SO NATURE
LA English
DT Article
ID cloud albedo; pollution; transport; impact; model
AB RECENTLY, Kiehl and Briegleb(1) evaluated the radiative forcing associated with the capacity of atmospheric sulphate aerosols to reflect solar radiation back into space, and compared this with the forcing associated with atmospheric greenhouse gases. They found that the (negative) climate forcing by the aerosols has strong regional character, with the greatest forcing over Northern Hemisphere land surfaces, whereas the (positive) forcing by greenhouse gases is distributed almost equally between the hemispheres and varies mainly as a function of latitude. Here we present simulations of the response of the climate system to these two types of forcing. We find that the global response to aerosol forcing is regionally heterogeneous, with a distribution that is different from the forcing pattern. The simulations also imply that, for equal magnitudes of forcing, the temperature response is markedly greater for carbon dioxide than for aerosol forcing. We conclude that to predict the global mean climate response to global mean forcing, it is necessary to separate out the different components of the forcing to which the climate system is sensitive.
C1 LAWRENCE LIVERMORE NATL LAB,DIV GLOBAL CLIMATE RES,LIVERMORE,CA 94551.
C3 United States Department of Energy (DOE); Lawrence Livermore National Laboratory
NR 25
TC 262
Z9 285
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 734
EP 737
DI 10.1038/369734a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100056
DA 2026-03-10
ER

PT J
AU DURKA, W
   SCHULZE, ED
   GEBAUER, G
   VOERKELIUS, S
AF DURKA, W
   SCHULZE, ED
   GEBAUER, G
   VOERKELIUS, S
TI EFFECTS OF FOREST DECLINE ON UPTAKE AND LEACHING OF DEPOSITED NITRATE DETERMINED FROM N-15 AND O-18 MEASUREMENTS
SO NATURE
LA English
DT Article
ID nitrogen isotope ratios; picea-abies forest; different compartments; ecosystems; spruce
AB ATTEMPTS to understand how atmospheric nitrogen deposition affects forest ecosystems(1,2) have been hampered by the lack of a direct method to trace the fate of the deposited nitrogen. Nitrate originating in the atmosphere has natural abundances of nitrogen and oxygen isotopes that differ measurably from those of soil nitrate(3). Here we present an analysis of the isotope ratios of nitrate in spring waters from eight forested watersheds, ranging from apparently healthy spruce plantations to those in decline owing to acidification. We find that for the healthy, slightly declining and limed sites, only 16-30% of the nitrate in spring water originates directly from the atmosphere without being processed in the soil, whereas for more severely damaged sites almost all of the atmospheric nitrate finds its way directly into the spring water. This suggests that acid-induced forest decline significantly inhibits nitrate consumption by soil microorganisms and trees, and that lining to ameliorate soil acidification restores the consumption of atmospheric nitrate. Nevertheless, in limed ecosystems total nitrate output remains high because of internal nitrate production by the ecosystem.
C1 HYDROISITOP,D-85301 SCHWEITENKIRCHEN,GERMANY.
RP DURKA, W (corresponding author), UNIV BAYREUTH,LEHRSTUHL PFLANZENOKOL,D-95440 BAYREUTH,GERMANY.
NR 18
TC 327
Z9 386
U1 2
U2 119
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 765
EP 767
DI 10.1038/372765a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200048
DA 2026-03-10
ER

PT J
AU IWAMURA, Y
   IRIKI, A
   TANAKA, M
AF IWAMURA, Y
   IRIKI, A
   TANAKA, M
TI BILATERAL HAND REPRESENTATION IN THE POSTCENTRAL SOMATOSENSORY CORTEX
SO NATURE
LA English
DT Article
ID vertical neuronal arrays; conscious monkey; receptive-field; rhesus-monkey; callosal connections; corpus-callosum; parietal cortex; m fascicularis; organization; gyrus
AB IN accordance with its important role in prehensile activity, a large cortical area is devoted to representation of the digits. Within this large cortical zone in the macaque somatosensory cortex, the complexity of neuronal receptive field characteristics increases from area 3b to areas 1 and 2 (refs 1-7). This increase in complexity continues into the upper bank of the intraparietal sulcus, where the somatosensory cortex adjoins the parietal association cortex. In this bank, callosal connections are much denser than in the more anterior part of this cortical zone(8-17). We have now discovered a substantial number of neurons with receptive fields on the bilateral hands. It was previously thought that neuronal receptive fields were restricted to the contralateral side in this cortical zone. Neurons with bilateral receptive fields were not found after lesioning the postcentral gyrus in the contralateral hemisphere. The majority of these neurons had receptive fields of the most complex types, representing multiple digits, indicating that the interhemispheric h anser of information occurs at higher levels of the hierarchical processing in each hemisphere.
RP IWAMURA, Y (corresponding author), TOHO UNIV,SCH MED,DEPT PHYSIOL,5-21-16 OMORI NISHI,TOKYO 143,JAPAN.
NR 30
TC 249
Z9 268
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 554
EP 556
DI 10.1038/369554a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400047
PM 8202155
DA 2026-03-10
ER

PT J
AU JACOBSON, RH
   ZHANG, XJ
   DUBOSE, RF
   MATTHEWS, BW
AF JACOBSON, RH
   ZHANG, XJ
   DUBOSE, RF
   MATTHEWS, BW
TI 3-DIMENSIONAL STRUCTURE OF BETA-GALACTOSIDASE FROM ESCHERICHIA-COLI
SO NATURE
LA English
DT Article
ID escherichia-coli; nucleotide-sequence; alpha-complementation; weissenberg camera; diffraction data; lacz gene; crystallography; refinement; expression; program
AB THE beta-galactosidase from Escherichia coli was instrumental in the development of the operon model(1), and today is one of the most commonly used enzymes in molecular biology. Here we report the structure of this protein and show that it is a tetramer with 222- point symmetry. The 1,023-amino-acid polypeptide chain(2,3) folds into five sequential domains, with an extended segment at the amino terminus. The participation of this amino-terminal segment in a subunit interface, coupled with the observation that each active site is made up of elements from two different subunits, provides a structural rationale for the phenomenon of alpha-complementation. The structure represents the longest polypeptide chain for which an atomic structure has been determined. Our results show that it is possible successfully to study non-viral protein crystals with unit cell dimensions in excess of 500 Angstrom and with relative molecular masses in the region of 2,000K per asymmetric unit. Non-crystallographic symmetry averaging proved to be a very powerful tool in the structure determination, as has been shown in other contexts(31,32).
C1 UNIV OREGON,INST MOLEC BIOL,EUGENE,OR 97403.
   UNIV OREGON,HOWARD HUGHES MED INST,EUGENE,OR 97403.
   UNIV OREGON,DEPT PHYS,EUGENE,OR 97403.
C3 University of Oregon; University of Oregon; Howard Hughes Medical Institute; University of Oregon
NR 32
TC 563
Z9 616
U1 0
U2 102
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 761
EP 766
DI 10.1038/369761a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100066
PM 8008071
DA 2026-03-10
ER

PT J
AU HABRAKEN, Y
   SUNG, P
   PRAKASH, L
   PRAKASH, S
AF HABRAKEN, Y
   SUNG, P
   PRAKASH, L
   PRAKASH, S
TI HOLIDAY JUNCTION CLEAVAGE BY YEAST RAD1 PROTEIN
SO NATURE
LA English
DT Article
ID dna-repair; escherichia-coli; holliday junctions; endonuclease; resolution
AB IN Saccharomyces cerevisiae, of the many genes required for excision repair of ultraviolet-damaged DNA, only RAD1 and RAD10 also function in genetic recombination(1). Complex formation between the RAD1 and RAD10 gene products(1) activates an endonucleolytic function that nicks single-stranded DNA(2,3) and negatively supercoiled double-stranded DNA(2). To characterize the recombination role of the proteins Rad1 and Rad10, we have investigated their interaction with the Holliday junction, a four-stranded structure that results from single-stranded crossover between two duplex DNA molecules and whose resolution is obligatory for the generation of mature recombinants. We show that Rad1 binds specifically to a Holliday junction and, in the presence of magnesium, catalyses the endonucleolytic cleavage of the junction. Junction cleavage by Rad1 proceeds sufficiently without Rad10, thus identifying Rad1 as the catalytic subunit of Rad1/Rad10 endonuclease.
C1 UNIV TEXAS,MED BRANCH,SEALY CTR MOLEC SCI,GALVESTON,TX 77555.
C3 University of Texas System; University of Texas Medical Branch Galveston
NR 13
TC 41
Z9 50
U1 1
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 531
EP 534
DI 10.1038/371531a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900060
PM 7935767
DA 2026-03-10
ER

PT J
AU DILWORTH, SM
   BREWSTER, CEP
   JONES, MD
   LANFRANCONE, L
   PELICCI, G
   PELICCI, PG
AF DILWORTH, SM
   BREWSTER, CEP
   JONES, MD
   LANFRANCONE, L
   PELICCI, G
   PELICCI, PG
TI TRANSFORMATION BY POLYOMA-VIRUS MIDDLE T-ANTIGEN INVOLVES THE BINDING AND TYROSINE PHOSPHORYLATION OF SHC
SO NATURE
LA English
DT Article
ID phosphatidylinositol kinase-activity; site-directed mutagenesis; protein; invitro; pp60c-src; 3-kinase; domain; cells
AB POLYOMA virus middle T-antigen converts normal fibroblasts to a fully transformed, tumorigenic phenotype1. It achieves this, at least in part, by binding and activating one of the non-receptor tyrosine kinases, pp60c-src, pp62c-yes or pp59c-fyn (reviewed in refs 2 and 3). As a result, middle T-antigen itself is phosphorylated on tyrosine residues4,5, one of which (Tyr 315) acts as a binding site for the SH2 domains of phosphatidylinositol-3'OH kinase 85K sub-unit6-8. Here we show that another tyrosine phosphorylation site in middle T-antigen (Tyr 250; refs 4, 5) acts as a binding region for the SH2 domain of the transforming protein Shc9. This results in Shc also becoming tyrosine-phosphorylated and binding to the SH2 domain of Grb2 (ref. 10). This probably stimulates p21ras activity through the mammalian homologue of the Drosophila guanine-nucleotide-exchange factor Sos (reviewed in ref. 11). We suggest that middle T-antigen transforms cells by acting as a functional homologue of an activated tyrosine kinase-associated growth-factor receptor.
C1 ROYAL POSTGRAD MED SCH, DEPT VIROL, LONDON W12 0NN, ENGLAND.
   UNIV PERUGIA, IST CLIN MED 1, I-06100 PERUGIA, ITALY.
C3 Imperial College London; University of Perugia
RP DILWORTH, SM (corresponding author), ROYAL POSTGRAD MED SCH, DEPT CHEM PATHOL, DU CANE RD, LONDON W12 0NN, ENGLAND.
NR 29
TC 202
Z9 219
U1 0
U2 5
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 87
EP 90
DI 10.1038/367087a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500066
PM 7509037
DA 2026-03-10
ER

PT J
AU REDFIELD, RJ
AF REDFIELD, RJ
TI MALE MUTATION-RATES AND THE COST OF SEX FOR FEMALES
SO NATURE
LA English
DT Article
ID deleterious mutations; recombination; reproduction; evolution; advantage
AB ALTHOUGH we do not know why sex evolved, the twofold cost of meiosis for females provides a standard against which postulated benefits of sex can be evaluated(1). The most reliable benefit is sex's ability to reduce the impact of deleterious mutations(2,3). But deleterious mutations may themselves generate a large and previously overlooked female-specific cost of sex. DNA sequence comparisons have confirmed Haldane's suggestion that most mutations arise in the male germ line(4,5); recent estimates of alpha, the ratio of male to female mutation rates, are ten, six and two in humans, primates and rodents, respectively(6-8). Consequently, male gametes may give progeny more mutations than the associated sexual recombination eliminates. Here I describe computer simulations showing that the cost of male mutations can easily exceed the benefits of recombination, causing females to produce fitter progeny by parthenogenesis than by mating. The persistence of sexual reproduction by females thus becomes even more problematic.
C1 CANADIAN INST ADV RES,PROGRAM EVOLUT BIOL,VANCOUVER V6T 1Z4,BC,CANADA.
C3 Canadian Institute for Advanced Research (CIFAR)
RP REDFIELD, RJ (corresponding author), UNIV BRITISH COLUMBIA,DEPT ZOOL,6270 UNIV BLVD,VANCOUVER V6T 1Z4,BC,CANADA.
NR 18
TC 80
Z9 84
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 145
EP 147
DI 10.1038/369145a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100048
PM 8177318
DA 2026-03-10
ER

PT J
AU KWON, H
   IMBALZANO, AN
   KHAVARI, PA
   KINGSTON, RE
   GREEN, MR
AF KWON, H
   IMBALZANO, AN
   KHAVARI, PA
   KINGSTON, RE
   GREEN, MR
TI NUCLEOSOME DISRUPTION AND ENHANCEMENT OF ACTIVATOR BINDING BY A HUMAN SW1/SNF COMPLEX
SO NATURE
LA English
DT Article
ID transcriptional activation; yeast; gal4; dna; snf2/swi2; proteins; invitro; family; chromatin; domains
AB CHROMATIN structure can affect the transcriptional activity of eukaryotic structural genes by blocking access of sequence-specific activator proteins (activators) to their promoter-binding sites(1). For example, the DNA-binding domain of the yeast GAL4 protein interacts very poorly with nucleosome cores compared with naked DNA(2) (and see below), and binding of other activators is even more strongly inhibited(2,3). The way in which activators bind to nucleosomal DNA is therefore a critical aspect of transcriptional activation. Genetic studies have suggested that the multi-component SWI/SNF complex of Saccharomyces cerevisiae facilitates transcription by altering the structure of the chromatin(4,5). Here we identify and partially purify a human homologue of the yeast SWI/SNF complex (hSWI/SNF complex). We show that a partially purified hSWI/SNF complex mediates the ATP-dependent disruption of a nucleosome, thereby enabling the activators, GAL4-VP16 and GAL4-AH, to bind within a nucleosome core. We conclude that the hSWI/SNF complex acts directly to reorganize chromatin structure so as to facilitate binding of transcription factors.
C1 UNIV MASSACHUSETTS,SCH MED,HOWARD HUGHES MED INST,PROGRAM MOLEC MED,WORCESTER,MA 01605.
   MASSACHUSETTS GEN HOSP,DEPT MOLEC BIOL,BOSTON,MA 02114.
   HARVARD UNIV,SCH MED,DEPT GENET,BOSTON,MA 02115.
   STANFORD UNIV,CTR MOILEC & GENET MED,HOWARD HUGHES MED INST,STANFORD,CA 94305.
C3 Howard Hughes Medical Institute; University of Massachusetts System; University of Massachusetts Worcester; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Harvard University; Harvard Medical School; Howard Hughes Medical Institute; Stanford University
NR 24
TC 682
Z9 806
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 477
EP 481
DI 10.1038/370477a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700061
PM 8047169
DA 2026-03-10
ER

PT J
AU KERSANACH, R
   BRINKMANN, H
   LIAUD, MF
   ZHANG, DX
   MARTIN, W
   CERFF, R
AF KERSANACH, R
   BRINKMANN, H
   LIAUD, MF
   ZHANG, DX
   MARTIN, W
   CERFF, R
TI 5 IDENTICAL INTRON POSITIONS IN ANCIENT DUPLICATED GENES OF EUBACTERIAL ORIGIN
SO NATURE
LA English
DT Article
ID chloroplast glyceraldehyde-3-phosphate dehydrogenase; self-splicing activity; group-ii intron; sequence-analysis; nuclear gene; maize; evolution; cloning; family; pea
AB IN 1985 Cornish-Bowden wrote ''although there is now much to suggest that introns are an ancient relic of primordial genes, convincing proof must await the discovery of clearly corresponding intron arrangements in genes that arose by duplication before the separation of prokaryotes and eukaryotes''1. Genes for chloroplast and cytosolic glyceraldehyde-3-phosphate dehydrogenases of eukaryotes are descendants of an ancient gene family that existed in the common ancestor of extant eubacteria. During eukaryotic evolution, both genes were transferred to the nucleus from the antecedents of present-day chloroplasts and mitochondria. respectively2-5. Here we report the discovery of five spliceosomal introns at positions that are precisely conserved between nuclear genes for this chloroplast/cytosol enzyme pair. These data provide strong evidence in favour of the 'introns early' hypothesis, which proposes that introns were present in the earliest cells, consistent with the idea that introns facilitated the assembly of primordial genes by accelerating the rate of exon shuffling6-13.
C1 TECH UNIV CAROLO WILHELMINA BRAUNSCHWEIG,INST GENET,POSTFACH 3329,D-38023 BRAUNSCHWEIG,GERMANY.
C3 Braunschweig University of Technology
NR 30
TC 97
Z9 101
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 387
EP 389
DI 10.1038/367387a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000074
PM 8114942
DA 2026-03-10
ER

PT J
AU DUNCAN, J
   WARD, R
   SHAPIRO, K
AF DUNCAN, J
   WARD, R
   SHAPIRO, K
TI DIRECT MEASUREMENT OF ATTENTIONAL DWELL TIME IN HUMAN VISION
SO NATURE
LA English
DT Article
ID visual-attention; search; parallel; cortex
AB IN vision, attentional limitations are reflected in interference or reduced accuracy when two objects must be identified at once in a brief display(1,2). In our experiments a brief temporal separation was introduced between the two objects to be identified. We measured how long the first object continued to interfere with the second, and hence the time course of the first object's attentional demand. According to conventional serial models, attention is assigned rapidly to one object after another, with a dwell time of only a few dozen milliseconds per item(3,4). But we report here that interference lasts for several hundred milliseconds-an order of magnitude more than the prediction of conventional models. We suggest that visual attention is not a high-speed switching mechanism, but a sustained state during which relevant objects become available to influence behaviour. This conclusion is consistent with recent physiological results in the monkey(5).
C1 UNIV CALGARY,DEPT PSYCHOL,CALGARY T2N 1N4,AB,CANADA.
C3 University of Calgary
RP DUNCAN, J (corresponding author), MRC,APPL PSYCHOL UNIT,15 CHAUCER RD,CAMBRIDGE CB2 2EF,ENGLAND.
NR 18
TC 512
Z9 568
U1 2
U2 45
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 313
EP 315
DI 10.1038/369313a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900047
PM 8183369
DA 2026-03-10
ER

PT J
AU MACIAS, MJ
   MUSACCHIO, A
   PONSTINGL, H
   NILGES, M
   SARASTE, M
   OSCHKINAT, H
AF MACIAS, MJ
   MUSACCHIO, A
   PONSTINGL, H
   NILGES, M
   SARASTE, M
   OSCHKINAT, H
TI STRUCTURE OF THE PLECKSTRIN HOMOLOGY DOMAIN FROM BETA-SPECTRIN
SO NATURE
LA English
DT Article
ID ph domain; proteins; spectroscopy; complex; nmr
AB The 'pleckstrin homology' or PH domain is a 100-residue protein module. It is present in many kinases, different isoforms of phospholipase C, GTPase-activating proteins and nucleotide-exchange factors(1-4). Its function is not known, but many proteins that contain a PH domain interact with GTP-binding proteins(5). The PH domain in beta-adrenergic receptor kinase may be involved in binding to the beta gamma subunits of a trimeric G-protein(3,4,6,7). We report here the three-dimensional structure of the PH domain of the cytoskeletal protein spectrin using homonuclear nuclear magnetic resonance. The core of the molecule is an antiparallel beta-sheet consisting of seven strands. The C terminus is folded into a long alpha-helix, and another helix is present in one of the surface loops. The molecule is electrostatically polarized and contains a pocket which may be involved in the binding of a ligand. There is a distant relationship to the peptidyl-prolyl-cis-trans-isomerase FKBP in which this pocket is involved in the binding of the macrocyclic compound FK506 (refs 8-11).
C1 EUROPEAN MOLEC BIOL LAB,D-69012 HEIDELBERG,GERMANY.
C3 European Molecular Biology Laboratory (EMBL)
NR 14
TC 220
Z9 244
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 675
EP 677
DI 10.1038/369675a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900063
PM 8208297
DA 2026-03-10
ER

PT J
AU NITTLER, LR
   ALEXANDER, CMO
   GAO, X
   WALKER, RM
   ZINNER, EK
AF NITTLER, LR
   ALEXANDER, CMO
   GAO, X
   WALKER, RM
   ZINNER, EK
TI INTERSTELLAR OXIDE GRAINS FROM THE TIESCHITZ ORDINARY CHONDRITE
SO NATURE
LA English
DT Article
ID oxygen isotopic abundances; red giants; stars; meteorites; evolution; al-26; murchison
AB MOST material in the Solar System has an isotopic composition that represents an average of the different stars that contributed material to the protostellar cloud. Primitive meteorites, on the other hand, preserve grains that retain the isotopic signatures of their individual stellar sources(1) and thus provide valuable insight into stellar and galactic evolution, nucleosynthesis, and solar nebular processes. A large number of pre-solar silicon carbide, graphite and diamond grains have now been isolated(1,2), but only three interstellar oxide grains have hitherto been recovered(3-7), even though oxygen-rich stars are believed to be the dominant source of dust in the Galaxy(8,9). We report here the isolation of 21 interstellar oxide grains from the Tieschitz meteorite. The grains exhibit a wide range of oxygen isotope compositions, indicating that they originated in several distinct stellar sources having different masses and initial compositions. There is also evidence for the presence of the short-lived radionuclide Al-26 in nine of the grains at the time they formed. Although the isotopic compositions of many of the grains are consistent with both observations and theoretical models of oxygen-rich red giant stars, a significant fraction have no observed stellar counterpart.
C1 WASHINGTON UNIV, DEPT PHYS, ST LOUIS, MO 63130 USA.
C3 Washington University (WUSTL)
RP NITTLER, LR (corresponding author), WASHINGTON UNIV, MCDONNELL CTR SPACE SCI, 1 BROOKINGS DR, ST LOUIS, MO 63130 USA.
NR 32
TC 187
Z9 200
U1 0
U2 9
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 443
EP 446
DI 10.1038/370443a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700050
DA 2026-03-10
ER

PT J
AU SUKHAREV, SI
   BLOUNT, P
   MARTINAC, B
   BLATTNER, FR
   KUNG, C
AF SUKHAREV, SI
   BLOUNT, P
   MARTINAC, B
   BLATTNER, FR
   KUNG, C
TI A LARGE-CONDUCTANCE MECHANOSENSITIVE CHANNEL IN E. COLI ENCODED BY MSCL ALONE
SO NATURE
LA English
DT Article
ID escherichia-coli; ion channels; transport; gene
AB ALL cellular organisms respond to vibration, touch, gravity or changes in osmolarity, although the molecules on which such mechanosensations depend are unknown. Candidates include certain channels that gate in response to membrane stretch(1,2). Patch-clamp experiments with Escherichia coli envelope have revealed a mechanosensitive channel with very large conductance (MscL) and one with a smaller conductance (MscS)(3-6) which may be important in osmoregulation. Here we have solubilized and fractionated the envelope, reconstituted the MscL activity in vitro, and traced it to a small protein, whose gene, mscL, we then cloned. Insertional disruption of mscL removes the channel activity, whereas reexpression of mscL borne on an expression plasmid restores it. MscL-channel activities were observed in material from a cell-free expression system with mscL as the only template. The mscL nucleotide sequence predicts a unique protein of only 136 amino acids, with a highly hydrophobic core and very different from porins or other known proteins.
C1 UNIV WISCONSIN,MOLEC BIOL LAB,MADISON,WI 53706.
   UNIV WISCONSIN,DEPT GENET,MADISON,WI 53706.
C3 University of Wisconsin System; University of Wisconsin Madison; University of Wisconsin System; University of Wisconsin Madison
NR 13
TC 626
Z9 729
U1 0
U2 70
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 265
EP 268
DI 10.1038/368265a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000062
PM 7511799
DA 2026-03-10
ER

PT J
AU HOWARD, RS
   LIVELY, CM
AF HOWARD, RS
   LIVELY, CM
TI PARASITISM, MUTATION ACCUMULATION AND THE MAINTENANCE OF SEX
SO NATURE
LA English
DT Article
ID recombination; reproduction
AB Two classes of models attempt to explain why obligate parthenogenesis only rarely replaces sexual reproduction in natural populations, in spite of the apparent reproductive advantage that parthenogens gain by producing only female offspring1. The mutation-accumulation models suggest that sex is adaptive because it purges the genome of harmful recurrent mutations2,3. The ecological genetic models postulate that sex is adaptive in variable environments, particularly when the relevant variation is generated by coevolutionary interactions with parasites4-7. Both of these models have considerable merit, but would seem to have limitations. The mutation-accumulation models require high rates of mutation3,8; the coevolutionary models require that parasites have severe fitness effects on their hosts9. In addition, parasites could select for clonal diversity and thereby erode any advantage that sex gains by producing variable progeny10. Here we consider the interaction between mutation accumulation and host-parasite cevolution. The results suggest that even moderate effects by parasites combined with reasonable rates of mutation could render sex evolutionarily stable against repeated invasion by clones.
RP HOWARD, RS (corresponding author), INDIANA UNIV,DEPT BIOL,BLOOMINGTON,IN 47405, USA.
NR 16
TC 260
Z9 286
U1 0
U2 78
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 554
EP 557
DI 10.1038/367554a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300057
PM 8107824
DA 2026-03-10
ER

PT J
AU OHKUMA, Y
   ROEDER, RG
AF OHKUMA, Y
   ROEDER, RG
TI REGULATION OF TFIIH ATPASE AND KINASE-ACTIVITIES BY TFIIE DURING ACTIVE INITIATION COMPLEX-FORMATION
SO NATURE
LA English
DT Article
ID rna polymerase-ii; transcription factor tfiie; carboxyl-terminal-domain; preinitiation complex; largest subunit; nonphosphorylated form; tata factor; phosphorylation; purification; motifs
AB THE general transcripton factor TFIIE, together with other general transcription factors, is essential for transcription initiation by RNA polymerase II1-5 TFIIE stimulates the TFIIH-dependent kinase activity that phosphorylates the carboxy-terminal domain of the largest subunit of RNA polymerase II6, and possesses a helicase activity(7). Here we show that human TFIIH has DNA-dependent ATPase activity and we characterize the stimulatory effect of TFIIE on both the ATPase and kinase activities. We demonstrate that extensive phosphorylation of RNA polymerase II occurs in a TFIIE-dependent manner in both the absence and presence of DNA but, in the latter case, only at a late stage of preinitiation complex assembly. We also show that TFIIH specifically phosphorylates three general transcription factors, human TFIID tau (TBP), TFIIE-alpha and TFIIF-alpha (RAP74).
RP OHKUMA, Y (corresponding author), ROCKEFELLER UNIV,BIOCHEM & MOLEC BIOL LAB,NEW YORK,NY 10021, USA.
NR 29
TC 148
Z9 203
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 160
EP 163
DI 10.1038/368160a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000070
PM 8166891
DA 2026-03-10
ER

PT J
AU ROBERTS, MB
   STRINGER, CB
   PARFITT, SA
AF ROBERTS, MB
   STRINGER, CB
   PARFITT, SA
TI A HOMINID TIBIA FROM MIDDLE PLEISTOCENE SEDIMENTS AT BOXGROVE, UK
SO NATURE
LA English
DT Article
ID quaternary
AB FOSSIL hominids from the earlier Middle Pleistocene of Europe are very rare and the Mauer mandible is generally accepted as the most ancient, with an estimated age of 500 kyr(1,2). We report here on the discovery of a human tibia, in association with stone tools, from calcareous silts at the Lower Palaeolithic site of Boxgrove, West Sussex, UK3,4 (Fig. 1). The silt units are correlated by mammalian biostratigraphy to an, as yet unnamed, major temperate stage or interglacial that immediately pre-dates the Anglian cold stage(5). Accordingly, the temperate sediments are equated with oxygen isotope stage 13 (ref. 6) and are therefore roughly coeval with the Mauer mandible. The massive tibia is the oldest hominid fragment from the British Isles and provides the first information about the manufacturers of the early Acheulian industries of Europe. It is assigned to Home cf. heidelbergensis.
C1 NAT HIST MUSEUM, DEPT PALAEONTOL, LONDON SW7 5BD, ENGLAND.
C3 Natural History Museum London
RP ROBERTS, MB (corresponding author), UCL, INST ARCHAEOL, FIELD ARCHAEOL UNIT, LONDON WC1H 0PY, ENGLAND.
NR 37
TC 112
Z9 119
U1 1
U2 6
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 311
EP 313
DI 10.1038/369311a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900046
PM 8183368
DA 2026-03-10
ER

PT J
AU STRASSER, A
   HARRIS, AW
   CORCORAN, LM
   CORY, S
AF STRASSER, A
   HARRIS, AW
   CORCORAN, LM
   CORY, S
TI BCL-2 EXPRESSION PROMOTES B-LYMPHOID BUT NOT T-LYMPHOID DEVELOPMENT IN SCID MICE
SO NATURE
LA English
DT Article
ID transgenic mice; cell-receptor; bone-marrow; mouse; survival; activation; apoptosis
AB EXPRESSION of antigen receptors is vital for the development of B and T lymphocytes. In mice with the scid mutation1,2, which are unable to make productive rearrangements of their immunoglobulin and T-cell receptor (TCR) genes, lymphopoiesis aborts at an early stage. The death of the immature lymphocytes by apoptosis3 is postulated to result from a failure to receive a survival signal induced by receptor engagement4. Consistent with this hypothesis, introduction of immunoglobulin or TCR transgenes into scid mice promoted an increase in B- or T-lymphoid cells, respectively5-7. As the protein encoded by the bcl-2 gene can inhibit cell death8,9, we tested whether lymphopoiesis could be rescued in scid mice by crossing in a bcl-2 transgene. Strikingly, the bcl-2/scid mice accumulated almost normal numbers of B-lymphoid cells which lacked surface immunoglobulin but expressed markers of maturity. T-cell development remained blocked. Introducing a TCR transgene enabled bcl-2/scid mice to develop normal numbers of CD4+8+ thymocytes even in the absence of immunological selection, suggesting that T cells become competent to respond to bcl-2 protein only after the TCR complex is displayed at the cell surface.
C1 ROYAL MELBOURNE HOSP, WALTER & ELIZA HALL INST MED RES, PARKVILLE, VIC 3050, AUSTRALIA.
C3 Walter & Eliza Hall Institute; Melbourne Health; Royal Melbourne Hospital
NR 28
TC 147
Z9 154
U1 0
U2 1
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 457
EP 460
DI 10.1038/368457a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000064
PM 8133891
DA 2026-03-10
ER

PT J
AU JESSOP, PG
   IKARIYA, T
   NOYORI, R
AF JESSOP, PG
   IKARIYA, T
   NOYORI, R
TI HOMOGENEOUS CATALYTIC-HYDROGENATION OF SUPERCRITICAL CARBON-DIOXIDE
SO NATURE
LA English
DT Article
ID formic-acid; fluids; dihydrogen; ruthenium; complexes; activation; chemistry; rhodium; system; co2
AB THE use of carbon dioxide as a starting material for the synthesis of organic compounds has long been a goal for synthetic chemists. The hydogenation of carbon dioxide to formic acid, methanol and other organic substances is particularly attractive, but has remained difficult. This route to formic acid has been described recently, based on the use of organometallic rhodium catalysts in dimethyl sulphoxide(1) and aqueous(2) solvents. We report here the efficient production of formic acid in a supercritical mixture of carbon dioxide and hydrogen containing a catalytic ruthenium(II) phosphine complex. The use of a supercritical phase, in which hydrogen is highly miscible, leads to a very high initial rate of reaction-up to 1,400 moles of formic acid per mote of catalyst per hour. The same reaction under identical conditions but in liquid organic solvents is much slower. Our results suggest that supercritical fluids represent a promising medium for homogeneous catalysis.
C1 RES DEV CORP JAPAN, MOLEC CATALYSIS PROJECT, TOYOTA, AICHI 47003, JAPAN.
C3 Japan Science & Technology Agency (JST)
NR 25
TC 615
Z9 672
U1 5
U2 351
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 231
EP 233
DI 10.1038/368231a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000051
DA 2026-03-10
ER

PT J
AU LAMBRIGHT, DG
   NOEL, JP
   HAMM, HE
   SIGLER, PB
AF LAMBRIGHT, DG
   NOEL, JP
   HAMM, HE
   SIGLER, PB
TI STRUCTURAL DETERMINANTS FOR ACTIVATION OF THE ALPHA-SUBUNIT OF A HETEROTRIMERIC G-PROTEIN
SO NATURE
LA English
DT Article
ID amino-acid-sequence; rod outer segments; elongation-factor-tu; gtp-binding protein; adenylate-cyclase; crystal-structure; saccharomyces-cerevisiae; signal transduction; guanine-nucleotides; escherichia-coli
AB The 1.8 Angstrom crystal structure of transducin alpha-GDP, when compared to that of the activated complex with GTP-gamma S, reveals the nature of the conformational changes that occur on activation of a heterotrimeric G-protein alpha-subunit. Structural changes initiated by direct contacts with the terminal phosphate of GTP propagate to regions that have been implicated in effector activation. The changes are distinct from those observed in other members of the GTPase superfamily.
C1 YALE UNIV,SCH MED,DEPT MOLEC BIOPHYS & BIOCHEM,NEW HAVEN,CT 06510.
   YALE UNIV,BOYER CTR MOLEC MED,HOWARD HUGHES MED INST,NEW HAVEN,CT 06510.
   UNIV ILLINOIS,DEPT PHYSIOL & BIOPHYS,CHICAGO,IL 60612.
C3 Yale University; Yale University; Howard Hughes Medical Institute; University of Illinois System; University of Illinois Chicago; University of Illinois Chicago Hospital
NR 44
TC 537
Z9 652
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 621
EP 628
DI 10.1038/369621a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900047
PM 8208289
DA 2026-03-10
ER

PT J
AU SAHAGIAN, DL
   SCHWARTZ, FW
   JACOBS, DK
AF SAHAGIAN, DL
   SCHWARTZ, FW
   JACOBS, DK
TI DIRECT ANTHROPOGENIC CONTRIBUTIONS TO SEA-LEVEL RISE IN THE 20TH-CENTURY
SO NATURE
LA English
DT Article
ID caspian sea; groundwater resources; saudi-arabia; aquifer
AB GLOBAL compilations of tide records indicate that sea level has been rising throughout the twentieth century1,2, with potentially dangerous consequences for low-lying coastal regions. Thermal expansion of ocean water3 and melting of alpine glaciers4 in response to increased atmospheric temperatures may have been responsible for some of this change, but human activities can also influence sea level directly. For example, the rise in sea level would have been even larger5 if large quantities of water had not been stored in reservoirs, and channelled into aquifers by irrigation projects. Here we show, however, that these and other human activities have together caused a net increase in sea levels over the past century. We estimate that a combination of groundwater withdrawal, surface water diversion and land-use changes has caused at least a third of the observed rise, and suggest that the contributions of climate-related effects must therefore be smaller than has been previously supposed.
C1 AMER MUSEUM NAT HIST,DEPT INVERTEBRATES,NEW YORK,NY 10024.
C3 American Museum of Natural History (AMNH)
RP SAHAGIAN, DL (corresponding author), OHIO STATE UNIV,DEPT GEOL SCI,COLUMBUS,OH 43210, USA.
NR 31
TC 77
Z9 82
U1 1
U2 40
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 54
EP 57
DI 10.1038/367054a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500055
DA 2026-03-10
ER

PT J
AU LOWIN, B
   HAHNE, M
   MATTMANN, C
   TSCHOPP, J
AF LOWIN, B
   HAHNE, M
   MATTMANN, C
   TSCHOPP, J
TI CYTOLYTIC T-CELL CYTOTOXICITY IS MEDIATED THROUGH PERFORIN AND FAS LYTIC PATHWAYS
SO NATURE
LA English
DT Article
ID lymphocytes-t; apoptosis; antibody; mice
AB THE recent generation of perforin knock-out mice(1,2) has demonstrated a crucial role for the pore-forming perforin in cytolytic T-lymphocyte (CTL)-mediated cytolysis. Perforin-deficient mice failed to clear lymphocytic choriomeningitis virus in vivo, yet substantial killing activity still remained in perforin-free CTLs in vitro, indicating the presence of (a) further lytic pathway(s). Fas is an apoptosis-signalling receptor molecule on the surface of a number of different cells. Here we report that both perforin-deficient and Fas-ligand-deficient CTLs show impaired lytic activity on all target cells tested, The killing activity was completely abolished when both pathways were inactivated by using target cells from Fas-receptor-deficient lpr mice and perforin-free CTL effector cells. Fas-ligand-based killing activity was triggered upon T-cell receptor occupancy and was directed to the cognate target cell. Thus, two complementary, specific cytotoxic mechanisms are functional in CTLs, one based on the secretion of lytic proteins and one which depends on cell-surface ligand-receptor interaction.
C1 UNIV LAUSANNE,INST BIOCHEM,CH-1066 EPALINGES,SWITZERLAND.
C3 University of Lausanne
NR 19
TC 990
Z9 1066
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 650
EP 652
DI 10.1038/370650a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000050
PM 7520535
DA 2026-03-10
ER

PT J
AU PLEY, HW
   FLAHERTY, KM
   MCKAY, DB
AF PLEY, HW
   FLAHERTY, KM
   MCKAY, DB
TI 3-DIMENSIONAL STRUCTURE OF A HAMMERHEAD RIBOZYME
SO NATURE
LA English
DT Article
ID self-cleavage reaction; virus satellite rna; efficient cleavage; molecular-dynamics; purine amino; oligoribonucleotides; phosphorothioate; guanosines; mechanism; sequence
AB The hammerhead ribozyme is a small catalytic RNA motif made up of three base-paired stems and a core of highly conserved, non-complementary nucleotides essential for catalysis. The X-ray crystallographic structure of a hammerhead RNA-RNA ribozyme-inhibitor complex at 2.6 Angstrom resolution reveals that the base-paired stems are A-form helices and that the core has two structural domains. The first domain is formed by the sequence 5'-CUGA following stem I and is a sharp turn identical to the uridine turn of transfer RNA, whereas the second is a non-Watson-Crick three-base-pair duplex with a divalent-ion binding site. The phosphodiester backbone of the DNA inhibitor strand is splayed out at the phosphate 5' to the cleavage site. The structure indicates that the ribozyme may destabilize a substrate strand in order to facilitate twisting of the substrate to allow cleavage of the scissile bond.
C1 STANFORD UNIV, SCH MED, DEPT BIOL STRUCT, BECKMAN LABS STRUCT BIOL, STANFORD, CA 94305 USA.
C3 Stanford University
NR 36
TC 967
Z9 1132
U1 2
U2 80
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 68
EP 74
DI 10.1038/372068a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800071
PM 7969422
DA 2026-03-10
ER

PT J
AU TAX, FE
   YEARGERS, JJ
   THOMAS, JH
AF TAX, FE
   YEARGERS, JJ
   THOMAS, JH
TI SEQUENCE OF C-ELEGANS LAG-2 REVEALS A CELL-SIGNALING DOMAIN SHARED WITH DELTA AND SERRATE OF DROSOPHILA
SO NATURE
LA English
DT Article
ID epidermal growth-factor; egf-like repeats; caenorhabditis-elegans; transmembrane protein; homologous genes; neurogenic gene; lin-12; glp-1; encodes; notch
AB THE lin-12 and glp-1 genes of Caenorhabditis elegans encode members of the Notch family of transmembrane proteins(1,2). Genetic studies indicate that the lin-12 and glp-1 proteins act as receptors in specific developmental cell interactions(3-6) and that their functions are partially redundant(7). lin-12 glp-1 double mutants display certain embryonic defects not found in either single mutant(7,8). The phenotype of this double mutant is called Lag, and recessive mutations in either of the genes lag-1 or lag-2 can also result in the Lag phenotype(7), indicating that these two genes may participate in the same cell interactions that require lin-12 or glp-1. We report here that lag-2 encodes a predicted transmembrane protein of 402 amino acids. The predicted extracellular region of lag-2 is similar to amino-terminal regions of Delta and Serrate, two Drosophila proteins that are thought to function as ligands for Notch(9-14). The region of similarity includes sequences related to epidermal growth factor (EGF) repeats. We have isolated lag-2(sa37), a dominant allele that shows specific genetic interactions with lin-12. The sa37 mutation causes a Gly-->Asp change in a conserved residue of an EGF motif. Because of its overall structure, its sequence similarity to Delta and Serrate, and its genetic interactions, ne suggest that lag-2 encodes an intercellular signal for the lin-12 and glp-1 receptors.
RP TAX, FE (corresponding author), UNIV WASHINGTON,DEPT GENET,SEATTLE,WA 98195, USA.
NR 31
TC 238
Z9 320
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 150
EP 154
DI 10.1038/368150a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000067
PM 8139658
DA 2026-03-10
ER

PT J
AU ULLRICH, O
   HORIUCHI, H
   BUCCI, C
   ZERIAL, M
AF ULLRICH, O
   HORIUCHI, H
   BUCCI, C
   ZERIAL, M
TI MEMBRANE ASSOCIATION OF RAB5 MEDIATED BY GDP-DISSOCIATION INHIBITOR AND ACCOMPANIED BY GDP/GTP EXCHANGE
SO NATURE
LA English
DT Article
ID gtp-binding protein; regulatory protein; smg p25a
AB THE Rab GTPases function as specific regulators of membrane transport(1-4) The GTP/GDP cycle is believed to control shuttling of Rab proteins between the cytosol and organelle membranes. In vitro, Rab proteins are removed from membranes by a protein that inhibits GDP dissociation (rabGDI)(5), which leads to formation of a cytosolic complex of Rab with the inhibitor protein(6-8). Here we use a purified Rab5-rabGDI complex in a permeabilized cell system to investigate how the cytosolic complexed form of Rab reassociates with the membrane. We find that exogenous Rab5 is correctly targeted and induces the formation of enlarged early endosomes, demonstrating that it is functionally active. Binding of Rab5 to the acceptor membrane is accompanied by release of the rabGDI protein into the cytosol. A transient GDP-Rab5 intermediate was detected which was subsequently converted into the GTP-bound form. Our results indicate that there is a multistep mechanism for the insertion of Rab5 into the membrane which is mediated by a guanine-nucleotide-exchange factor.
C1 EUROPEAN MOLEC BIOL LAB,D-69012 HEIDELBERG,GERMANY.
C3 European Molecular Biology Laboratory (EMBL)
NR 17
TC 272
Z9 309
U1 0
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 157
EP 160
DI 10.1038/368157a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000069
PM 8139660
DA 2026-03-10
ER

PT J
AU RUETER, P
   RABUS, R
   WILKES, H
   AECKERSBERG, F
   RAINEY, FA
   JANNASCH, HW
   WIDDEL, F
AF RUETER, P
   RABUS, R
   WILKES, H
   AECKERSBERG, F
   RAINEY, FA
   JANNASCH, HW
   WIDDEL, F
TI ANAEROBIC OXIDATION OF HYDROCARBONS IN CRUDE-OIL BY NEW TYPES OF SULFATE-REDUCING BACTERIA
SO NATURE
LA English
DT Article
ID hydrothermal vent site; 16s rdna analysis; microbial-degradation; guaymas basin; north-sea; sulfate; petroleum; toluene; sediments
AB MANY crude oil constituents are biodegradable in the presence of oxygen; however, a substantial anaerobic degradation has never been demonstrated(1,2). An unusually low content of n-alkanes in oils of certain deposits is commonly attributed to selective utilization of these hydrocarbons by aerobic microorganisms(3,4). On the other hand, oil wells and production fluids were shown to harbour anaerobic sulphate-reducing bacteria(5-8), but their actual electron donors and carbon sources were unknown. On the basis of nutritional properties of various bacterial isolates it was assumed that fatty acids and H-2 are potential electron donors for sulphate reduction in situ(5-8). Here we demonstrate that hydrocarbons in crude oil are used directly by sulphate-reducing bacteria growing under strictly anoxic conditions. A moderately thermophilic pure culture selectively utilizes n-alkanes in oil for sulphate reduction to sulphide. In addition, a mesophilic sulphate-reducing enrichment culture is shown to oxidize alkylbenzenes in oil. Thus, sulphate-reducing bacteria utilizing aliphatic and aromatic hydrocarbons as electron donors may present a significant source of sulphide in oil deposits and oil production plants.
C1 MAX PLANCK INST MARINE MIKROBIOL, D-28359 BREMEN, GERMANY.
   FORSCHUNGSZENTRUM JULICH, FORSCHUNGSZENTRUM, INST ERDOL & ORGAN GEOCHEM ICG4, D-52428 JULICH, GERMANY.
   DEUTSCH SAMMLUNG MIKROORGANISMEN & ZELLKULTUREN, D-38124 BRAUNSCHWEIG, GERMANY.
   WOODS HOLE OCEANOG INST, WOODS HOLE, MA 02543 USA.
C3 Max Planck Society; Helmholtz Association; Julich Research Centre; Leibniz Association; Leibniz Institut fur Deutsche Sammlung von Mikroorganismen und Zellkulturen (DSMZ); Woods Hole Oceanographic Institution
NR 26
TC 362
Z9 414
U1 1
U2 131
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 455
EP 458
DI 10.1038/372455a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200054
PM 7984238
DA 2026-03-10
ER

PT J
AU CEPEK, KL
   SHAW, SK
   PARKER, CM
   RUSSELL, GJ
   MORROW, JS
   RIMM, DL
   BRENNER, MB
AF CEPEK, KL
   SHAW, SK
   PARKER, CM
   RUSSELL, GJ
   MORROW, JS
   RIMM, DL
   BRENNER, MB
TI ADHESION BETWEEN EPITHELIAL-CELLS AND T-LYMPHOCYTES MEDIATED BY E-CADHERIN AND THE ALPHA(E)BETA(7) INTEGRIN
SO NATURE
LA English
DT Article
ID monoclonal-antibody; vla-4; expression; molecules; receptor; proteins; homology; antigen; subunit; family
AB IN contrast to sessile cell types, lymphocytes migrate through the vasculature to become diffusely distributed in tissues or organized in lymphoid structures. A complex array of adhesion molecules including selectins, integrins and their counter-receptors mediate lymphocyte homing and migration into tissues and may be constitutively expressed or induced(1,2). However, the molecules that mediate the tissue-specific retention of lymphocytes within the parenchyma have not been identified. Along the epithelium at the basolateral surface of enterocytes, intestinal intraepithelial lymphocytes are found. These T cells of the mucosal immune system serve as a model for the tissue-specific compartmentalization of lymphocytes. We investigated whether the localization of these intestinal intraepithelial lymphocytes could be mediated by specific interactions between adhesion molecules expressed selectively on this subpopulation of T cells and tissue-restricted adhesion molecules on epithelial cells. Here we show that heterotypic adhesive interactions between epithelial cells and intraepithelial lymphocytes in vitro are mediated by E-cadherin and the alpha(E) beta(7) integrin.
C1 HARVARD UNIV,DIV MED SCI,BOSTON,MA 02115.
   YALE UNIV,DEPT PATHOL,NEW HAVEN,CT 06510.
C3 Harvard University; Yale University
RP CEPEK, KL (corresponding author), HARVARD UNIV,BRIGHAM & WOMENS HOSP,SCH MED,DEPT RHEUMATOL & IMMUNOL,LYMPHOCYTE BIOL SECT,BOSTON,MA 02115, USA.
NR 27
TC 1030
Z9 1154
U1 0
U2 34
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 190
EP 193
DI 10.1038/372190a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800059
PM 7969453
DA 2026-03-10
ER

PT J
AU BENDER, M
   SOWERS, T
   DICKSON, ML
   ORCHARDO, J
   GROOTES, P
   MAYEWSKI, PA
   MEESE, DA
AF BENDER, M
   SOWERS, T
   DICKSON, ML
   ORCHARDO, J
   GROOTES, P
   MAYEWSKI, PA
   MEESE, DA
TI CLIMATE CORRELATIONS BETWEEN GREENLAND AND ANTARCTICA DURING THE PAST 100,000 YEARS
SO NATURE
LA English
DT Article
ID vostok ice-core; isotopic composition; glacial period; polar ice; record; ocean; paleoclimate; oxygen; gisp2; cycle
AB THE ice cores recovered from central Greenland by the GRIP(1,2) and GISP2(3) projects record 22 interstadial (warm) events during the part of the last glaciation spanning 20-105 kyr before present. The ice core from Vostok, east Antarctica, records nine interstadials during this period(4,5). Here we explore links between Greenland and Antarctic climate during the last glaciation using a high-resolution chronology derived by correlating oxygen isotope data for trapped O-2 in the GISP2 and Vostok cores. We find that interstadials occurred in east Antarctica whenever those in Greenland lasted longer than 2,000 years. Our results suggest that partial deglaciation and changes in ocean circulation are partly responsible for the climate teleconnection between Greenland and Antarctica. Ice older than 115 kyr in the GISP2 core shows rapid variations in the delta(18)O of O-2 that have no counterpart in the Vostok record. The age-depth relationship, and thus the climate record, in this part of the GISP2, core appears to be significantly disturbed.
C1 COLUMBIA UNIV, LAMONT DOHERTY GEOL OBSERV, PALISADES, NY 10964 USA.
   UNIV WASHINGTON, DEPT GEOL SCI, SEATTLE, WA 98105 USA.
   UNIV WASHINGTON, QUATERNARY RES CTR, SEATTLE, WA 98105 USA.
   UNIV NEW HAMPSHIRE, INST STUDY EARTH OCEANS & SPACE, GLACIER RES GRP, DURHAM, NH 03824 USA.
   USA, COLD REG RES & ENGN LAB, HANOVER, NH 03755 USA.
C3 Columbia University; University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle; University System Of New Hampshire; University of New Hampshire; United States Department of Defense; United States Army; U.S. Army Corps of Engineers; U.S. Army Engineer Research & Development Center (ERDC); Cold Regions Research & Engineering Laboratory (CRREL)
RP BENDER, M (corresponding author), UNIV RHODE ISL, GRAD SCH OCEANOG, KINGSTON, RI 02881 USA.
NR 50
TC 312
Z9 354
U1 0
U2 56
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 663
EP 666
DI 10.1038/372663a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700082
DA 2026-03-10
ER

PT J
AU WENDLING, F
   MARASKOVSKY, E
   DEBILI, N
   FLORINDO, C
   TEEPE, M
   TITEUX, M
   METHIA, N
   BRETONGORIUS, J
   COSMAN, D
   VAINCHENKER, W
AF WENDLING, F
   MARASKOVSKY, E
   DEBILI, N
   FLORINDO, C
   TEEPE, M
   TITEUX, M
   METHIA, N
   BRETONGORIUS, J
   COSMAN, D
   VAINCHENKER, W
TI C-MPL LIGAND IS A HUMORAL REGULATOR OF MEGAKARYOCYTOPOIESIS
SO NATURE
LA English
DT Article
ID colony-stimulating factor; factor receptor superfamily; molecular-cloning; gamma-chain; b-cells; growth; purification; member; thrombopoietin; identification
AB MEGAKARYOCYTOPOIESIS is the cellular developmental process that leads to platelet production. At least two humoral growth factors mag be necessary for megakaryocyte proliferation and maturation. One is a megakaryocyte-colony stimulating factor (MK-CSF) which induces the proliferation and differentiation of megakaryocyte progenitors(1,2), and the second, thrombopoietin, is a megakaryocyte maturation factor(3). Neither of these factors has been fully characterized. The proto-oncogene c-mpl, an orphan member of the haematopoietin receptor family(4-6), is specifically involved in megakaryocyte regulation(7). Here we present evidence that the c-mpl-encoded receptor binds a ligand (c-Mpl ligand) which is a humoral factor implicated in platelet homeostasis. Our results suggest that c-Mpl ligand, thrombopoietin and MK-CSF might be the same molecule.
C1 HOP HENRI MONDOR,INSERM,U91,F-94010 CRETEIL,FRANCE.
   IMMUNEX RES & DEV CORP,SEATTLE,WA 98101.
C3 Universite Paris-Est-Creteil-Val-de-Marne (UPEC); Assistance Publique Hopitaux Paris (APHP); Hopital Universitaire Henri-Mondor - APHP; Institut National de la Sante et de la Recherche Medicale (Inserm)
RP WENDLING, F (corresponding author), INST GUSTAVE ROUSSY,INSERM,U362,F-94805 VILLEJUIF,FRANCE.
NR 23
TC 653
Z9 715
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 571
EP 574
DI 10.1038/369571a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400053
PM 8202160
DA 2026-03-10
ER

PT J
AU KNOPSGERRITS, PP
   DEVOS, D
   THIBAULTSTARZYK, F
   JACOBS, PA
AF KNOPSGERRITS, PP
   DEVOS, D
   THIBAULTSTARZYK, F
   JACOBS, PA
TI ZEOLITE-ENCAPSULATED MN(II) COMPLEXES AS CATALYSTS FOR SELECTIVE ALKENE OXIDATION
SO NATURE
LA English
DT Article
ID manganese
AB COMPLEXES of manganese(II) with bipyridine (bpy) have the potential to act as catalysts for oxidation of alkanes and alkenes when the complex is oxidized in acidic conditions(1-6). But their catalytic activity in solution is limited by their catalase activity(7)-their tendency to decompose H2O2. Because of their polynuclear nature such complexes cannot induce epoxidation of alkenes, and other epoxidation catalysts suffer from self-oxidation and side reactions(8-11). Moreover, all of these homogeneous catalytic processes require phase-transfer conditions. Here we report that, when encapsulated in the supercages of zeolites X and Y, cis-[Mn(bpy)(2)](2+) complexes can catalyse selective epoxidation of alkenes without complications from competing processes such as self-oxidation or catalase activity. Epoxidation of cycloalkenes is followed by acid-catalysed ring-opening, carbon-carbon bond cleavage and formation of alkenedioic acids (Fig. 1). All of the various intermediates in the process can be obtained selectively by controlling the reaction conditions and zeolite acidity. Thus this supramolecular system provides a clean, one-step heterogeneous catalytic route to useful industrial products.
C1 KATHOLIEKE UNIV LEUVEN,CTR OPPERVLAKTECHEM & KATALYSE,B-3001 HEVERLEE,BELGIUM.
C3 KU Leuven
NR 22
TC 209
Z9 218
U1 1
U2 69
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 543
EP 546
DI 10.1038/369543a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400043
DA 2026-03-10
ER

PT J
AU ROSENMUND, C
   CARR, DW
   BERGESON, SE
   NILAVER, G
   SCOTT, JD
   WESTBROOK, GL
AF ROSENMUND, C
   CARR, DW
   BERGESON, SE
   NILAVER, G
   SCOTT, JD
   WESTBROOK, GL
TI ANCHORING OF PROTEIN-KINASE-A IS REQUIRED FOR MODULATION OF AMPA/KAINATE RECEPTORS ON HIPPOCAMPAL-NEURONS
SO NATURE
LA English
DT Article
ID methyl-d-aspartate; regulatory subunit; ion channels; camp; cloning; kainate; rii; localization; accumulation; expression
AB PHOSPHORYLATION of molecules involved in synaptic transmission by multifunctional protein kinases modulates both pre- and postsynaptic events in the central nervous system(1,2). The positioning of kinases near their substrates may be an important part of the regulatory mechanism. The A-kinase-anchoring proteins (AKAPs; ref. 3) are known to bind the regulatory subunit of cyclic AMP-dependent protein kinase A with nanomolar affinity. Here we show that anchoring of protein kinase A by AKAPs is required for the modulation of alpha-amino-3-hydroxy-5'methyl-4-isoxazole-propionic acid (AMPA)/kainate channels(4,5). Intracellular perfusion of cultured hippocampal neurons with peptides derived from the conserved kinase binding region of AKAPs prevented the protein kinase A-mediated regulation of AMPA/kainate currents as well as fast excitatory synaptic currents. This effect could be overcome by adding the purified catalytic subunit of protein kinase. A control peptide lacking kinase-binding activity had no effect. To our knowledge, these results provide the first evidence that anchoring of protein kinase A is crucial in the regulation of synaptic function.
C1 OREGON HLTH SCI UNIV,VOLLUM INST,PORTLAND,OR 97201.
   OREGON HLTH SCI UNIV,DEPT NEUROL,PORTLAND,OR 97201.
C3 Oregon Health & Science University; Oregon Health & Science University
NR 29
TC 322
Z9 359
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 853
EP 856
DI 10.1038/368853a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700071
PM 8159245
DA 2026-03-10
ER

PT J
AU ASHMAN, TL
   SCHOEN, DJ
AF ASHMAN, TL
   SCHOEN, DJ
TI HOW LONG SHOULD FLOWERS LIVE
SO NATURE
LA English
DT Article
ID leaf longevity; cost
AB FLORAL longevity, the length of time a flower remains open and functional, varies among plant species. Flowers of some species live less than one day (morning glory), whereas others live for several weeks (orchids)(1-3). By viewing floral longevity as a resource allocation stratey(2,4), we now incorporate the study of its evolution into the well developed theoretical framework provided by evolutionarily stable strategy models that address variation in life history(5,6). Flowers must remain open to contribute to plant fitness through ovule fertilization and pollen dissemination, when they require resources for respiratory maintenance and pollinator attraction. Accordingly, floral senescence should occur when the expected fitness gain per unit of floral maintenance investment diminishes to the point,where it becomes more profitable to construct a new flower than to maintain an existing one. Our experimental evidence supports floral longevity as an adaptation that balances rates of pollen receipt and removal against thr cost of floral maintenance.
C1 MCGILL UNIV, DEPT BIOL, MONTREAL H3A 1B1, PQ, CANADA.
C3 McGill University
NR 23
TC 301
Z9 346
U1 2
U2 109
PU NATURE RESEARCH
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 788
EP 791
DI 10.1038/371788a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800056
DA 2026-03-10
ER

PT J
AU TAKAGAKI, Y
   MANLEY, JL
AF TAKAGAKI, Y
   MANLEY, JL
TI A POLYADENYLATION FACTOR SUBUNIT IS THE HUMAN HOMOLOG OF THE DROSOPHILA SUPPRESSOR OF FORKED PROTEIN
SO NATURE
LA English
DT Article
ID pre-messenger-rnas; poly(a) polymerase; saccharomyces-cerevisiae; specificity factor; binding domain; melanogaster; cleavage; expression; sequence; genes
AB POLYADENYLATION of messenger RNA precursors is a complex process that requires multiple protein factors (for reviews, see refs 1, 2). Cleavage stimulation factor (CstF) is one of these, functioning together with cleavage-polyadenylation specificity factor, two cleavage factors, and poly(A)(+) polymerase(3-7) CstF is composed of three subunits of M(r) 77, 64 and 50K(8,9). The 64K(10) and 50K(11) subunits contain, respectively, an RNP-type RNA-binding domain that contacts the pre-mRNA and transducin repeats characteristic of G-protein beta-subunits. Here we report the cloning and characterization of the 77K subunit of human CstF (referred to as 77K). We show that the 77K subunit is required for formation of active CstF and bridges the 64K and 50K subunits. Sequence analyses indicate that the 77K subunit is the homologue of the protein encoded by the Drosophila melanogaster suppressor of forked (su(f)) gene(12). Mutations in su(f) can enhance or suppress the effects of transposable element insertions(13), and our data indicate that this is due to changes in polyadenylation. Both the 77K subunit and the su(f) protein share homology with Saccharomyces cerevisiae RNA14 previously shown to be involved in mRNA metabolism(14). Our results thus also indicate that components of the complex polyadenylation machinery are conserved from yeast to man.
RP TAKAGAKI, Y (corresponding author), COLUMBIA UNIV,DEPT BIOL SCI,NEW YORK,NY 10027, USA.
NR 30
TC 119
Z9 138
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 471
EP 474
DI 10.1038/372471a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200059
PM 7984242
DA 2026-03-10
ER

PT J
AU ROBINSON, CV
   GROSS, M
   EYLES, SJ
   EWBANK, JJ
   MAYHEW, M
   HARTL, FU
   DOBSON, CM
   RADFORD, SE
AF ROBINSON, CV
   GROSS, M
   EYLES, SJ
   EWBANK, JJ
   MAYHEW, M
   HARTL, FU
   DOBSON, CM
   RADFORD, SE
TI CONFORMATION OF GROEL-BOUND ALPHA-LACTALBUMIN PROBED BY MASS-SPECTROMETRY
SO NATURE
LA English
DT Article
ID molten globule state; group hydrogen-exchange; egg-white lysozyme; structural characterization; 2-dimensional nmr; chaperonin groel; 1.7-a resolution; central cavity; hen lysozyme; protein
AB The conformation of a three-disulphide derivative of bovine alpha-lactalbumin bound to the molecular chaperone GroEL has been investigated by monitoring directly its hydrogen exchange kinetics using electrospray ionization mass spectrometry. The bound protein is weakly protected from exchange to an extent closely similar to that of an uncomplexed molten globule state of the three-disulphide protein. Binding to GroEL in this system appears to involve relatively disordered partly folded states resembling intermediates formed in the very early stages of kinetic folding of many proteins in vitro.
C1 UNIV OXFORD,OXFORD CTR MOLEC SCI,NEW CHEM LAB,OXFORD OX1 3QT,ENGLAND.
   UNIV OXFORD,OXFORD CTR MOLEC SCI,DYSON PERRINS LAB,OXFORD OX1 3QT,ENGLAND.
   EUROPEAN MOLEC BIOL LAB,D-69117 HEIDELBERG,GERMANY.
   MEM SLOAN KETTERING CANC CTR,CELLULAR BIOCHEM & BIOPHYS PROGRAM,NEW YORK,NY 10021.
   MEM SLOAN KETTERING CANC CTR,HOWARD HUGHES MED INST,NEW YORK,NY 10021.
C3 University of Oxford; University of Oxford; European Molecular Biology Laboratory (EMBL); Memorial Sloan Kettering Cancer Center; Memorial Sloan Kettering Cancer Center; Howard Hughes Medical Institute
NR 51
TC 206
Z9 219
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 646
EP 651
DI 10.1038/372646a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700077
PM 7990955
DA 2026-03-10
ER

PT J
AU LONBERG, N
   TAYLOR, LD
   HARDING, FA
   TROUNSTINE, M
   HIGGINS, KM
   SCHRAMM, SR
   KUO, CC
   MASHAYEKH, R
   WYMORE, K
   MCCABE, JG
   MUNOZOREGAN, D
   ODONNELL, SL
   LAPACHET, ESG
   BENGOECHEA, T
   FISHWILD, DM
   CARMACK, CE
   KAY, RM
   HUSZAR, D
AF LONBERG, N
   TAYLOR, LD
   HARDING, FA
   TROUNSTINE, M
   HIGGINS, KM
   SCHRAMM, SR
   KUO, CC
   MASHAYEKH, R
   WYMORE, K
   MCCABE, JG
   MUNOZOREGAN, D
   ODONNELL, SL
   LAPACHET, ESG
   BENGOECHEA, T
   FISHWILD, DM
   CARMACK, CE
   KAY, RM
   HUSZAR, D
TI ANTIGEN-SPECIFIC HUMAN-ANTIBODIES FROM MICE COMPRISING 4 DISTINCT GENETIC MODIFICATIONS
SO NATURE
LA English
DT Article
ID cell-specific enhancer; monoclonal-antibody; immunoglobulin; recombination; rejection; locus
AB HUMAN sequence monoclonal antibodies, which in theory combine high specificity with low immunogenicity, represent a class of potential therapeutic agents. But nearly 20 years after Kohler and Milstein first developed methods for obtaining mouse antibodies(1), no comparable technology exists for reliably obtaining high-affinity human antibodies directed against selected targets. Thus, rodent antibodies(2), and in vitro modified derivatives of rodent antibodies(3-5), are still being used and tested in the clinic. The rodent system has certain clear advantages; mice are easy to immunize, are not tolerant to most human antigens, and their B cells form stable hybridoma cell lines. To exploit these advantages, we have developed transgenic mice that express human IgM, IgG and Ig kappa in the absence of mouse IgM or Ig kappa. We report here that these mice contain human sequence transgenes that undergo V(D)J joining, heavy-chain class switching, and somatic mutation to generate a repertoire of human sequence immunoglobulins. They are also homozygous for targeted mutations that disrupt V(D)J rearrangement at the endogenous heavy- and kappa light-chain loci. We have immunized the mice with human proteins and isolated hybridomas secreting human IgG kappa antigen-specific antibodies.
C1 GENPHARM INT,MT VIEW,CA 94043.
NR 18
TC 294
Z9 2023
U1 1
U2 26
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 856
EP 859
DI 10.1038/368856a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700072
PM 8159246
DA 2026-03-10
ER

PT J
AU COLLEDGE, WH
   CARLTON, MBL
   UDY, GB
   EVANS, MJ
AF COLLEDGE, WH
   CARLTON, MBL
   UDY, GB
   EVANS, MJ
TI DISRUPTION OF C-MOS CAUSES PARTHENOGENETIC DEVELOPMENT OF UNFERTILIZED MOUSE EGGS
SO NATURE
LA English
DT Article
ID proto-oncogene product; protooncogene product; meiotic maturation; xenopus eggs; kinase; gene; fertilization; expression; activation; oocytes
AB THE c-mos proto-oncogene encodes a 37-39K cytoplasmic serine/threonine kinase(1) implicated in the meiotic maturation events during murine spermatogenesis(2) and oogenesis(3-6). In Xenopus, ectopic expression of pp39(mos) can promote both the meiotic maturation of oocytes(7-9) and also arrest the cleavage of blastomeres(10) To elucidate the role of pp39(mos) we have generated homozygous mutant mice by gene targeting in embryonic stem cells(11). These mice are viable and mutant males are fertile, demonstrating that pp39(mos) is not essential for spermatogenesis. In contrast, mutant females, have a reduced fertility because of the failure of mature eggs to arrest during meiosis. c-mos(-1-) oocytes undergo germinal vesicle breakdown and extrusion of both polar bodies followed in some cases by progression into cleavage. Mutant females also develop ovarian cysts. These results demonstrate that a major role for pp39(mos) is to prevent the spontaneous parthenogenetic activation of unfertilized eggs.
C1 UNIV CAMBRIDGE,DEPT GENET,CAMBRIDGE CB2 1QR,CAMBS,ENGLAND.
   RUAKURA AGR CTR,HAMILTON,NEW ZEALAND.
C3 University of Cambridge; AgResearch - New Zealand
RP COLLEDGE, WH (corresponding author), UNIV CAMBRIDGE,WELLCOME CRC INST CANC & DEV BIOL,TENNIS COURT RD,CAMBRIDGE CB2 1QR,CAMBS,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 23
TC 418
Z9 459
U1 0
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 65
EP 68
DI 10.1038/370065a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100060
PM 8015609
DA 2026-03-10
ER

PT J
AU KORZHINSKY, MA
   TKACHENKO, SI
   SHMULOVICH, KI
   TARAN, YA
   STEINBERG, GS
AF KORZHINSKY, MA
   TKACHENKO, SI
   SHMULOVICH, KI
   TARAN, YA
   STEINBERG, GS
TI DISCOVERY OF A PURE RHENIUM MINERAL AT KUDRIAVY VOLCANO
SO NATURE
LA English
DT Article
ID sulfide; complex; mo; re
AB KUDRIAVY volcano on Iturup island in the Kuril are is an active calc-alkaline volcano. It has not erupted this century; its current volcanic activity is characterized by hot (up to 910 degrees C) gas jets which have been stable for at least 30 years. The composition of the gaseous emissions is typical of high-temperature fumaroles, but we report here the discovery of unusual subsurface sublimates associated with one gas jet-a sulphide mineral containing rhenium as the only cation. To our knowledge, this is the first reported occurrence of a pure rhenium mineral. The concentration of rhenium in the fumarole gas is only 2-10 p.p.b., so the condensation of pure rhenium sulphide from this gas requires both enrichment of rhenium by eight orders of magnitude and remarkable selectivity. Rhenium is generally believed to exist in only trace amounts at the Earth's surface, but our findings demonstrate that it can be readily mobilized, dispersed and concentrated by degassing magmas.
C1 RUSSIAN ACAD SCI,INST VOLCAN GEOL & GEOCHEM,PETROPAVLOVSK KAMC 683006,RUSSIA.
   INST VOLCANOL & GEODYNAM ANSRF,YUZHNO SAKHALINSK 693008,RUSSIA.
C3 Institute of Volcanology & Seismology, Far Eastern Branch, RAS; Russian Academy of Sciences
RP KORZHINSKY, MA (corresponding author), RUSSIAN ACAD SCI,INST EXPTL MINERAL,CHERNOGOLOVKA 142432,RUSSIA.
NR 10
TC 128
Z9 147
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 51
EP 52
DI 10.1038/369051a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000049
DA 2026-03-10
ER

PT J
AU MUHLRAD, D
   PARKER, R
AF MUHLRAD, D
   PARKER, R
TI PREMATURE TRANSLATIONAL TERMINATION TRIGGERS MESSENGER-RNA DECAPPING
SO NATURE
LA English
DT Article
ID messenger-rna decay; nonsense mutations; endonucleolytic cleavage; saccharomyces-cerevisiae; rich sequences; degradation; poly(a); yeast; deadenylation; step
AB THE degradation of messenger RNA in eukaryotic cells is initiated by endonucleolytic cleavage(1,2) or by shortening of the poly(A) tail(3-6), which for some mRNAs activates a deadenylation-dependent decapping reaction(7). One type of rapid mRNA degradation in eukaryotes is caused by premature termination of translation(8,9). This turnover process prevents the translation of aberrant mRNAs(10,11), may affect the abundance and splicing pattern of nuclear transcripts(12,13), and may be involved in the aetiology of human genetic disease(14). Here we show that premature translational termination in yeast triggers decapping, independent of deadenylation, thereby exposing the transcript to 5'-to-3' degradation. Inactivation of the 5'-to-3' exonuclease reveals an additional 3'-to-5' pathway of mRNA turnover. These observations provide in vivo evidence for two new mechanisms of mRNA decay.
RP MUHLRAD, D (corresponding author), UNIV ARIZONA,DEPT MOLEC & CELLULAR BIOL,LIFE SCI S,TUCSON,AZ 85721, USA.
NR 23
TC 342
Z9 394
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 578
EP 581
DI 10.1038/370578a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700061
PM 8052314
DA 2026-03-10
ER

PT J
AU LU, DS
   WILLARD, D
   PATEL, IR
   KADWELL, S
   OVERTON, L
   KOST, T
   LUTHER, M
   CHEN, WB
   WOYCHIK, RP
   WILKISON, WO
   CONE, RD
AF LU, DS
   WILLARD, D
   PATEL, IR
   KADWELL, S
   OVERTON, L
   KOST, T
   LUTHER, M
   CHEN, WB
   WOYCHIK, RP
   WILKISON, WO
   CONE, RD
TI AGOUTI PROTEIN IS AN ANTAGONIST OF THE MELANOCYTE-STIMULATING-HORMONE RECEPTOR
SO NATURE
LA English
DT Article
ID molecular-cloning; melanocortin receptor; expression; locus; assay; cells; mice
AB THE genetic loci agouti and extension control the relative amounts of eumelanin (brown-black) and phaeomelanin (yellow-red) pigments in mammals(1): extension encodes the receptor for melanocyte-stimulating hormone (MSH)(2) and agouti encodes a novel 131-amino-acid protein containing a signal sequence(3,4). Agouti, which is produced in the hair follicle(5), acts on follicular melanocytes(6) to inhibit alpha-MSH-induced eumelanin production, resulting in the subterminal band of phaeomelanin often visible in mammalian fur. Here we use partially purified agouti protein to demonstrate that agouti is a high-affinity antagonist of the MSH receptor and blocks alpha-MSH stimulation of adenylyl cyclase, the effector through which alpha-MSH induces eumelanin synthesis, Agouti was also found to be an antagonist of the melanocortin-4 receptor(7,8), a related MSH-binding receptor. Consequently, the obesity caused by ectopic expression of agouti in the lethal yellow (A(y)) mouse(9) may be due to the inhibition of melanocortin reteptor(s) outside the hair follicle.
C1 GLAXO INC, RES INST, DIV MOLEC SCI, RES TRIANGLE PK, NC 27709 USA.
   OREGON HLTH SCI UNIV, VOLLUM INST ADV BIOMED RES, PORTLAND, OR 97201 USA.
   OAK RIDGE NATL LAB, DIV BIOL, OAK RIDGE, TN 37831 USA.
C3 GlaxoSmithKline; Glaxosmithkline USA; Oregon Health & Science University; United States Department of Energy (DOE); Oak Ridge National Laboratory
NR 25
TC 941
Z9 1086
U1 1
U2 67
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 799
EP 802
DI 10.1038/371799a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800060
PM 7935841
DA 2026-03-10
ER

PT J
AU ZOHARY, E
   SHADLEN, MN
   NEWSOME, WT
AF ZOHARY, E
   SHADLEN, MN
   NEWSOME, WT
TI CORRELATED NEURONAL DISCHARGE RATE AND ITS IMPLICATIONS FOR PSYCHOPHYSICAL PERFORMANCE
SO NATURE
LA English
DT Article
ID visual area mt; cortical-neurons; single neurons; monkey; discrimination; microstimulation; orientation; frequency; stimuli; motion
AB SINGLE neurone can signal subtle changes in the sensory environment with surprising fidelity, often matching the perceptual sensitivity of trained psychophysical observers This similarity poses an intriguing puzzle: why is psychophysical sensitivity not greater than that of single neurons? Pooling responses across neurons should average out noise in the activity of single cells, leading to substantially improved psychophysical performance. If, however, noise is correlated among these neurons, the beneficial effects of pooling would be diminished(10-12). To assess correlation within a pool, the responses of pairs of neurons were recorded simultaneously during repeated stimulus presentations. We report here that the observed covariation in spike count was relatively weak, the correlation coefficient averaging 0.12. A theoretical analysis revealed, however, that weak correlation can limit substantially the signalling capacity of the pool. In addition, theory suggests a relationship between neuronal responses and psychophysical decisions which may prove useful for identifying cell populations underlying specific perceptual capacities.
C1 STANFORD UNIV,SCH MED,DEPT NEUROBIOL,STANFORD,CA 94305.
C3 Stanford University
NR 22
TC 941
Z9 1105
U1 1
U2 41
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 140
EP 143
DI 10.1038/370140a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400057
PM 8022482
DA 2026-03-10
ER

PT J
AU WITTHUHN, BA
   SILVENNOINEN, O
   MIURA, O
   LAI, KS
   CWIK, C
   LIU, ET
   IHLE, JN
AF WITTHUHN, BA
   SILVENNOINEN, O
   MIURA, O
   LAI, KS
   CWIK, C
   LIU, ET
   IHLE, JN
TI INVOLVEMENT OF THE JAK-3 JANUS KINASE IN SIGNALING BY INTERLEUKIN-2 AND INTERLEUKIN-4 IN LYMPHOID AND MYELOID CELLS
SO NATURE
LA English
DT Article
ID protein-tyrosine kinase; receptor gamma-chain; erythropoietin receptor; interferon-alpha/beta; transduction; phosphorylation; pathway; family; il-2
AB MANY cytokines function through interaction with receptors of the cytokine receptor superfamily. Although lacking catalytic domains, cytokine receptors couple ligand binding to induction of protein tyrosine phosphorylation. Recent studie(1-10) have shown that one or more of the Janus kinase family members (Jaks) associate with cytokine receptors and are tyrosine phosphorylated and activated following ligand binding. Here we describe a new Jak family kinase, Jak-3, and demonstrate that Jak-3, and to a lesser extent Jak-1, are tyrosine phosphorylated and Jak-3 is activated in the responses to interleukin-2 and interleukin-4 in T cells and myeloid cells. Jak-3 activation requires the serine-rich, membrane-proximal domain of the interleukin-3 receptor beta-chain, but does not require the acidic domain that is required for association and activation of Src family kinases.
C1 ST JUDE CHILDRENS RES HOSP, DEPT BIOCHEM, MEMPHIS, TN 38105 USA.
   UNIV N CAROLINA, SCH MED, CHAPEL HILL, NC 27599 USA.
   UNIV N CAROLINA, LINEBERGER COMPREHENS CANC CTR, DEPT BIOL, CHAPEL HILL, NC 27599 USA.
C3 St Jude Children's Research Hospital; University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina School of Medicine; University of North Carolina; University of North Carolina Chapel Hill
NR 30
TC 595
Z9 631
U1 1
U2 24
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 153
EP 157
DI 10.1038/370153a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400061
PM 8022486
DA 2026-03-10
ER

PT J
AU KOHTZ, JD
   JAMISON, SF
   WILL, CL
   ZUO, P
   LUHRMANN, R
   GARCIABLANCO, MA
   MANLEY, JL
AF KOHTZ, JD
   JAMISON, SF
   WILL, CL
   ZUO, P
   LUHRMANN, R
   GARCIABLANCO, MA
   MANLEY, JL
TI PROTEIN-PROTEIN INTERACTIONS AND 5'-SPLICE-SITE RECOGNITION IN MAMMALIAN MESSENGER-RNA PRECURSORS
SO NATURE
LA English
DT Article
ID pre-messenger-rna; 5' splice site; small nuclear ribonucleoprotein; u1 snrna; assembly pathway; binding proteins; factor sc35; complex; invitro; purification
AB Exactly how specific splice sites are recognized during the processing of complex precursor messenger RNAs is not clear. Small nuclear ribonucleoprotein particles (snRNPs) are involved, but are not sufficient by themselves to define splice sites. Now a human protein essential for splicing in vitro, called alternative splicing factor/splicing factor 2, is shown to cooperate with the U1 snRNP particle in binding pre-mRNA. This cooperation is probably achieved by specific interactions between the arginine/serine-rich domain of the splicing factor and a similar region in a U1 snRNP-specific protein.
C1 DUKE UNIV,MED CTR,DEPT MOLEC CANC BIOL,DURHAM,NC 27710.
   DUKE UNIV,MED CTR,DEPT MICROBIOL,DURHAM,NC 27710.
   DUKE UNIV,MED CTR,DEPT MED,DURHAM,NC 27710.
C3 Duke University; Duke University; Duke University
RP KOHTZ, JD (corresponding author), COLUMBIA UNIV,DEPT BIOL SCI,NEW YORK,NY 10027, USA.
NR 50
TC 567
Z9 653
U1 1
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 119
EP 124
DI 10.1038/368119a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000056
PM 8139654
DA 2026-03-10
ER

PT J
AU MASSONNET, D
   FEIGL, K
   ROSSI, M
   ADRAGNA, F
AF MASSONNET, D
   FEIGL, K
   ROSSI, M
   ADRAGNA, F
TI RADAR INTERFEROMETRIC MAPPING OF DEFORMATION IN THE YEAR AFTER THE LANDERS EARTHQUAKE
SO NATURE
LA English
DT Article
ID 1992 landers; crustal deformation; southern california; june 1992; sequence; stress; field; displacements; faults; april
AB ALTHOUGH the 1992 Landers, California, earthquake sequence occurred in an area well sampled by geodetic networks(1-3), the postseismic deformation in the months following the earthquake has been measured at only 15 geodetic stations(4). Another shortcoming in the geodetic coverage occurs west of the primary rupture, where the existing geodetic observations suggest, but cannot resolve, sympathetic slip on secondary faults(1). Such measurements, which are needed to place the Landers earthquake sequence in the context of a recurring seismic cycle in California, can be obtained with the dense spatial coverage provided by satellite radar interferometry(5-9). Here we present radar maps of the surface deformation field which reveal features that would otherwise have been poorly sampled, particularly if the earthquake had occurred in a less accessible area. We see triggered slip at the level of several centimetres as far as 100 km from the primary rupture, and can resolve the geodetic signal of at least one small (magnitude similar to 5) aftershock. The amount of surface slip following the main shock is less than a decimetre, and is consistent with an exponential decay time of several months for the postseismic deformation.
C1 CNRS,F-31400 TOULOUSE,FRANCE.
C3 Centre National de la Recherche Scientifique (CNRS)
RP MASSONNET, D (corresponding author), CTR NATL ETUD SPATIALES,18 AVE EDOUARD BELIN,F-31055 TOULOUSE,FRANCE.
NR 27
TC 242
Z9 314
U1 1
U2 39
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 227
EP 230
DI 10.1038/369227a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700054
DA 2026-03-10
ER

PT J
AU DAVIES, JL
   KAWAGUCHI, Y
   BENNETT, ST
   COPEMAN, JB
   CORDELL, HJ
   PRITCHARD, LE
   REED, PW
   GOUGH, SCL
   JENKINS, SC
   PALMER, SM
   BALFOUR, KM
   ROWE, BR
   FARRALL, M
   BARNETT, AH
   BAIN, SC
   TODD, JA
AF DAVIES, JL
   KAWAGUCHI, Y
   BENNETT, ST
   COPEMAN, JB
   CORDELL, HJ
   PRITCHARD, LE
   REED, PW
   GOUGH, SCL
   JENKINS, SC
   PALMER, SM
   BALFOUR, KM
   ROWE, BR
   FARRALL, M
   BARNETT, AH
   BAIN, SC
   TODD, JA
TI A GENOME-WIDE SEARCH FOR HUMAN TYPE-1 DIABETES SUSCEPTIBILITY GENES
SO NATURE
LA English
DT Article
ID mellitus iddm; insulin gene; linkage analysis; quantitative traits; mendelian factors; hla; polymorphism; region; locus; mice
AB We have searched the human genome for genes that predispose to type 1 (insulin-dependent) diabetes mellitus using semi-automated fluorescence-based technology and linkage analysis. In addition to IDDM1 (in the major histocompatibility complex on chromosome 6p21) and IDDM2 (in the insulin gene region on chromosome 11p15), eighteen different chromosome regions showed some positive evidence of linkage to disease. Linkages to chromosomes iio (IDDM4) and 6q (IDDM5) were confirmed by replication, and chromosome is may encode a fifth disease locus. There are probably no genes with large effects aside from IDDM1. Therefore polygenic inheritance Is indicated, with a major locus at the major histocompatibility complex.
C1 UNIV OXFORD,WELLCOME TRUST CTR HUMAN GENET,OXFORD OX3 7BN,ENGLAND.
   UNIV BIRMINGHAM,BIRMINGHAM HEARTLANDS HOSP,DEPT MED DIABET ENDOCRINOL,BIRMINGHAM B9 5SS,W MIDLANDS,ENGLAND.
   HAMMERSMITH HOSP,MRC,CLIN RES CTR,LONDON W12 0NN,ENGLAND.
C3 University of Oxford; Wellcome Centre for Human Genetics; Heart of England NHS Foundation Trust; Heartlands Hospital; University of Birmingham; Imperial College London; Medical Research Council Clinical Trials Unit
RP DAVIES, JL (corresponding author), UNIV OXFORD,JOHN RADCLIFFE HOSP,NUFFIELD DEPT SURG,OXFORD OX3 9DU,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 50
TC 1227
Z9 1335
U1 0
U2 63
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 130
EP 136
DI 10.1038/371130a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100055
PM 8072542
DA 2026-03-10
ER

PT J
AU WARREN, RW
   NAGY, L
   SELEGUE, J
   GATES, J
   CARROLL, S
AF WARREN, RW
   NAGY, L
   SELEGUE, J
   GATES, J
   CARROLL, S
TI EVOLUTION OF HOMEOTIC GENE-REGULATION AND FUNCTION IN FLIES AND BUTTERFLIES
SO NATURE
LA English
DT Article
ID bithorax-complex; drosophila; expression
AB IT has been proposed that the evolution of homeotic genes parallels, and to some degree directs, the evolution of segment diversity in the myriapod-insect lineage(1-3). But the discovery of discrete Antennapedia complex (ANT-C) and bithorax complex (BX-C) gene members in crustacea(4) chelicerates(5), annelids(6-8) and various insects(9-11), as well as in vertebrates(12), indicates that the expansion and diversification of homeotic genes preceded the diversification of arthropods and insects. How, then, have these genes influenced the evolution of body plans? To address this question, we now examine homeotic gene expression and regulation in butterflies (Lepidoptera), which, unlike flies, possess larval abdominal limbs and two pairs of wings. We show that the difference in larval limb number between these insects results from striking changes in BX-C gene regulation in the butterfly abdomen, and we deduce that the wing-patterning genes regulated by Ultrabithorax have diverged in the course of butterfly and fly evolution. These findings have general implications for the role of homeotic genes in animal evolution.
C1 UNIV WISCONSIN, HOWARD HUGHES MED INST, MADISON, WI 53706 USA.
   UNIV WISCONSIN, MOLEC BIOL LAB, MADISON, WI 53706 USA.
C3 Howard Hughes Medical Institute; University of Wisconsin System; University of Wisconsin Madison; University of Wisconsin System; University of Wisconsin Madison
NR 31
TC 167
Z9 192
U1 0
U2 35
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 458
EP 461
DI 10.1038/372458a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200055
PM 7840822
DA 2026-03-10
ER

PT J
AU FLEURY, V
   KAUFMAN, JH
   HIBBERT, DB
AF FLEURY, V
   KAUFMAN, JH
   HIBBERT, DB
TI MECHANISM OF A MORPHOLOGY TRANSITION IN RAMIFIED ELECTROCHEMICAL GROWTH
SO NATURE
LA English
DT Article
ID zinc electrodeposition; deposition; velocity; selection; patterns; support
AB RAMIFIED patterns are common in nature, and have been much studied in the context of non-equilibrium growth and aggregation phenomena1-4. Processes that are known to produce ramified growth may lead to a range of morphologies, depending on experimental parameters such as growth speed. The mechanism of the transitions between different morphologies is not fully understood1-4. Electrochemical deposition of ramified deposits5-29 is often regarded as a model system for studying two-dimensional pattern formation. Here we present experimental results which allow us to propose a mechanism for the transition between fractal-like, ramified growth and rectilinear, filamentary growth of electrodeposits. We show that electroconvection of the metal ions in solution induces physical displacements of the growing branches, which results in fanning and splitting of the tips. At sufficiently high growth speeds, breaking of the symmetry with which this fanning occurs can lead to a change in growth morphology. We suggest that mechanical motions and disturbances may play a role in other pattern-forming systems.
C1 IBM CORP, DIV RES, ALMADEN RES CTR, SAN JOSE, CA 95114 USA.
   UNIV NEW S WALES, DEPT ANALYT CHEM, KENSINGTON, NSW 2033, AUSTRALIA.
C3 International Business Machines (IBM); IBM USA; University of New South Wales Sydney
RP FLEURY, V (corresponding author), ECOLE POLYTECH, PHYS MAT CONDENSEE LAB, F-91128 PALAISEAU, FRANCE.
NR 30
TC 125
Z9 137
U1 1
U2 35
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 435
EP 438
DI 10.1038/367435a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900046
DA 2026-03-10
ER

PT J
AU ALMOHANNA, FA
   CADDY, KWT
   BOLSOVER, SR
AF ALMOHANNA, FA
   CADDY, KWT
   BOLSOVER, SR
TI THE NUCLEUS IS INSULATED FROM LARGE CYTOSOLIC CALCIUM-ION CHANGES
SO NATURE
LA English
DT Article
ID smooth-muscle cells; c-fos expression; intracellular calcium; confocal microscopy; pore complex; neurons; transcription; transients; gradients; dynamics
AB EXTRACELLULAR events regulate functions in the cell nucleus by means of calcium ions acting through effector enzymes1-5. Recently, the traditional view of the nuclear pore as freely permeable to small ions6,7 has been questioned as a result of reports that nuclear calcium can be regulated independently of cytosolic calcium8-12.  We have used confocal microscopy of fluorescent Ca2+ indicators to investigate the Ca2+ dynamics between cytosol and nucleus in neurons. We find that a previously reported amplification of Ca2+ changes in the nucleus13-16 is a measurement artefact. Small changes of cytosolic Ca2+ cause equally rapid changes in nuclear Ca2+, consistent with the free diffusion of Ca2+ through nuclear pores.  In contrast,  large cytosolic Ca2+ increases (above 300 nM) are attempted in the nucleus.  Our results show the nuclear envelope shapes but does not block the  passage of Ca2+ signals from cytosol to nucleus.
C1 UNIV LONDON UNIV COLL,DEPT PHYSIOL,LONDON WC1E 6BT,ENGLAND.
C3 University of London; University College London
FU Wellcome Trust Funding Source: Medline
NR 25
TC 229
Z9 240
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 745
EP 750
DI 10.1038/367745a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100061
PM 7993399
DA 2026-03-10
ER

PT J
AU KEIL, RG
   HU, FS
   TSAMAKIS, EC
   HEDGES, JI
AF KEIL, RG
   HU, FS
   TSAMAKIS, EC
   HEDGES, JI
TI POLLEN IN MARINE-SEDIMENTS AS AN INDICATOR OF OXIDATION OF ORGANIC-MATTER
SO NATURE
LA English
DT Article
ID rates
AB Organic carbon burial in marine sediments generates virtually all atmospheric oxygen, and provides a long-term sink for about 20% of all carbon(1,2); it is therefore important to understand the mechanisms controlling organic carbon preservation. There is a fraction of organic matter that is preserved under reducing conditions but which can be rapidly oxidized if exposed to molecular oxygen(3-6). It is not clear, however, how much of the total organic matter preserved in marine sediments is oxygen-sensitive. Here we present results from a relict turbidite in the Madeira abyssal plain which suggest that pollen grains can be used as a sensitive tracer of oxygen-sensitive organic carbon. We find that pollen grains were completely degraded within 10 kyr in the presence of diffusively introduced oxygen, but were well preserved for at least 100 kyr under anoxic conditions. We also present pollen data from the Pacific Northwest continental shelf, which suggest that oxic degradation can explain the decrease in organic carbon with depth commonly observed in coastal sediments.
C1 UNIV WASHINGTON,COLL FOREST RESOURCES,SEATTLE,WA 98195.
C3 University of Washington; University of Washington Seattle
RP KEIL, RG (corresponding author), UNIV WASHINGTON,SCH OCEANOG,WB-10,SEATTLE,WA 98195, USA.
NR 32
TC 72
Z9 78
U1 1
U2 23
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 639
EP 641
DI 10.1038/369639a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900052
DA 2026-03-10
ER

PT J
AU BRIEL, UG
   HENRY, JP
AF BRIEL, UG
   HENRY, JP
TI AN X-RAY TEMPERATURE MAP OF THE MERGING GALAXY CLUSTER A2256
SO NATURE
LA English
DT Article
ID coma cluster; dark matter; einstein; rosat; mass
AB RICH clusters of galaxies are the largest bound masses in the Universe, but it has been difficult to determine just how massive they are(1,2). Observations of the velocities of individual galaxies, whose motions reflect the gravitational potential that they feel, have the difficulty that only the component of motion along the line of sight can be measured-the transverse component is unknown. X-ray observations seem to provide a better estimate of the mass(3-6), under the assumption that the hot X-ray-emitting gas is relaxed because of its isotropic velocity dispersion, but they have been hampered by a lack of adequate simultaneous spatial and spectral resolution. Here we present a map of the distribution of X-ray temperatures in the cluster Abell 2256, which has been thought to be nearly relaxed. Our map demonstrates that this is not the case, and implies that the assumption that the cluster is relaxed will lead to an underestimate of the true mass. As most clusters show stilt less evidence of being relaxed than A2256, their mass estimates may have larger errors.
C1 UNIV HAWAII,INST ASTRON,HONOLULU,HI 96822.
C3 University of Hawaii System
RP BRIEL, UG (corresponding author), MAX PLANCK INST EXTRATERR PHYS,D-85740 GARCHING,GERMANY.
NR 32
TC 79
Z9 81
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 439
EP 441
DI 10.1038/372439a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200048
DA 2026-03-10
ER

PT J
AU WAISBREN, SJ
   GEIBEL, JP
   MODLIN, IM
   BORON, WF
AF WAISBREN, SJ
   GEIBEL, JP
   MODLIN, IM
   BORON, WF
TI UNUSUAL PERMEABILITY PROPERTIES OF GASTRIC GLAND-CELLS
SO NATURE
LA English
DT Article
ID nh3; permeation; membranes
AB PHYSIOLOGISTS have long pondered the riddle of why the stomach is itself not digested by the very juice it secretes. One explanation is that a mucus-bicarbonate barrier, coating the stomach lumen as well as superficial portions of gastric glands, prevents autodigestion(1). However, this leaves unanswered the question of what protects cells deeper in the glands, which seem to lack a mucus barrier(2). These are the parietal and chief cells, which secrete acid and pepsin. Using perfused single gastric glands from rabbit, we recently found that intracellular pH is uniquely resistant to extreme degrees of luminal acidification(2), suggesting that the apical (luminal) barrier might also exclude ammonia and carbon dioxide, to which cell membranes are generally highly permeable(3,4). We now show that this is indeed the case. There are three reports of membranes with very low permeabilities to NH3 (refs 5-7), and none of membranes impermeable to CO2.
C1 YALE UNIV,SCH MED,DEPT SURG,GASTROINTESTINAL SURG PATHOBIOL RES UNIT,NEW HAVEN,CT 06510.
C3 Yale University
RP WAISBREN, SJ (corresponding author), YALE UNIV,SCH MED,DEPT CELLULAR & MOLEC PHYSIOL,NEW HAVEN,CT 06510, USA.
NR 20
TC 140
Z9 150
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 332
EP 335
DI 10.1038/368332a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500045
PM 8127367
DA 2026-03-10
ER

PT J
AU BUSTURIA, A
   LAWRENCE, PA
AF BUSTURIA, A
   LAWRENCE, PA
TI REGULATION OF CELL NUMBER IN DROSOPHILA
SO NATURE
LA English
DT Article
ID imaginal wing disk; pattern-formation; fushi-tarazu; fate map; melanogaster; embryo; larval; localization; parasegments; regeneration
AB DURING animal development, different parts grow independently (such as the left and right hands) but they stop growing when they reach the correct size. In most insects, growth of the epidermis is so controlled that, at each moult, there is a precise and proportionate increase in cell number(1). The mechanisms responsible for this size regulation are not known(2), but rigid programming of the number of cell divisions is not a requirement as even sister cells in an epithelial sheet divide variably(3-5). In the abdomen of dipterans, such as Drosophila, the opportunity for regulation is limited, because mitoses occur only in the embryo and during metamorphosis and not during larval growth. Here we used embryos with a reduced number of cells in the abdominal primordia to determine,whether they can regulate towards the normal during subsequent growth. In contrast to expectations(6-8), we find no evidence for regulation of cell number.
RP BUSTURIA, A (corresponding author), MRC, MOLEC BIOL LAB, HILLS RD, CAMBRIDGE CB2 2QH, ENGLAND.
NR 30
TC 25
Z9 28
U1 0
U2 5
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 561
EP 563
DI 10.1038/370561a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700056
PM 7914352
DA 2026-03-10
ER

PT J
AU WIENS, DA
   MCGUIRE, JJ
   SHORE, PJ
   BEVIS, MG
   DRAUNIDALO, K
   PRASAD, G
   HELU, SP
AF WIENS, DA
   MCGUIRE, JJ
   SHORE, PJ
   BEVIS, MG
   DRAUNIDALO, K
   PRASAD, G
   HELU, SP
TI A DEEP EARTHQUAKE AFTERSHOCK SEQUENCE AND IMPLICATIONS FOR THE RUPTURE MECHANISM OF DEEP EARTHQUAKES
SO NATURE
LA English
DT Article
ID intermediate-depth earthquakes; focus earthquakes; downgoing lithosphere; high-pressure; seismic zone; olivine; parameters; evolution; mantle
AB A distinguishing characteristic of deep earthquakes has been the absence of observable aftershock sequences(1,2). Here we report the first extensive deep-earthquake aftershock sequence to be observed; it was recorded by an array of eight broadband seismographs following the 9 March 1994 deep Tonga earthquake. The aftershocks show a power-law decay with time following the main shock, as is typical of shallow events. Most of the well located aftershocks are concentrated along a steeply dipping plane consistent with one of the nodal planes of the main-shock mechanism and the mechanisms of three large aftershocks. Assuming these aftershocks denote the main-shock rupture area, they define a 50 x 65 km fault plane extending across the entire width of the active seismic zone and into the surrounding aseismic region. The width of the aftershock zone is wider than the expected width of the metastable olivine sedge, demonstrating that either the width of the metastable olivine material exceeds previous estimates, or the aftershocks are not confined in such a wedge.
C1 UNIV HAWAII,HAWAII INST GEOPHYS & PLANETOL,HONOLULU,HI 96822.
   FIJI MINERAL RESOURCES DEPT,SUVA,FIJI.
   TONGA MINIST LANDS SURVEY & NAT RESOURCES,NUKUALOFA,TONGA.
C3 University of Hawaii System
RP WIENS, DA (corresponding author), WASHINGTON UNIV,DEPT EARTH & PLANETARY SCI,ST LOUIS,MO 63130, USA.
NR 30
TC 81
Z9 93
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 540
EP 543
DI 10.1038/372540a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200049
DA 2026-03-10
ER

PT J
AU PARKER, GA
   SIMMONS, LW
AF PARKER, GA
   SIMMONS, LW
TI EVOLUTION OF PHENOTYPIC OPTIMA AND COPULA DURATION IN DUNGFLIES
SO NATURE
LA English
DT Article
ID marginal value theorem; scatophaga-stercoraria; sperm competition; dung fly; fly; strategy; size; diet
AB THERE is growing evidence that adaptation may relate to precise conditions of an individual's phenotype, though previous studies have concentrated on discontinuous variation(1). We show here that the copula duration of male dungflies, a widely cited example of optimality in biology(2-5), is tuned precisely and continuously to the size of the copulating male. During copulation, new sperm displace previously stored sperm at a rate that shows exponentially diminishing returns(6). Thus at the optimal copula duration a male's paternity gains from continued copulation drop below that expected from searching for a new female. Small males have lower rates of sperm displacement(7); they also have less prospect of copulation by take-over of females from other males(8,9). Both effects predict that small males will copulate for longer, although displacement differences exert much the stronger influence. Observed copula durations are negatively correlated with size and concur with the optimality model across the natural male size range. This represents one of the first quantitative demonstrations of optimal responses covarying with a continuous aspect of phenotype. Phenotype-limited optimality profiles pose interesting evolutionary questions.
RP PARKER, GA (corresponding author), UNIV LIVERPOOL, DEPT ENVIRONM & EVOLUT BIOL, POB 147, LIVERPOOL L69 3BX, ENGLAND.
NR 23
TC 122
Z9 126
U1 0
U2 35
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 53
EP 56
DI 10.1038/370053a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100056
DA 2026-03-10
ER

PT J
AU AMOR, JC
   HARRISON, DH
   KAHN, RA
   RINGE, D
AF AMOR, JC
   HARRISON, DH
   KAHN, RA
   RINGE, D
TI STRUCTURE OF THE HUMAN ADP-RIBOSYLATION FACTOR-1 COMPLEXED WITH GDP
SO NATURE
LA English
DT Article
ID phospholipase-d; protein; binding; resolution; cofactor; arf
AB ADP-ribosylation factors (ARFs) are essential and ubiquitous in eukaryotes, being involved in vesicular transport and functioning as an activator of phospholipase D (refs 1, 2) and cholera toxin(3,4). The functions of ARF proteins in membrane traffic and organelle integrity(5,6) are intimately tied to its reversible association with membranes and specific interactions with membrane phospholipids. One common feature of these functions is their regulation by the binding and hydrolysis of GTP. Here we report the three-dimensional structure of full-length human ARF1 (M(r) 21,000) in its GDP-bound non-myristoylated form. The presence of a unique amino-terminal alpha-helix and loop, together with differences in Mg2+ ligation and the existence of a non-crystallographic dimer, set this structure apart from other GTP-binding proteins. These features provide a structural basis for the GTP-dependent modulation of membrane affinity, the lack of intrinsic GTPase activity, and the nature of effector binding surfaces.
C1 BRANDEIS UNIV,ROSENSTIEL BASIC MED SCI RES CTR,WALTHAM,MA 02254.
   BRANDEIS UNIV,DEPT BIOCHEM,PROGRAM BIOORGAN CHEM,WALTHAM,MA 02254.
   BRANDEIS UNIV,DEPT CHEM & BIOCHEM,WALTHAM,MA 02254.
   NCI,DEV THERAPEUT PROGRAM,BIOL CHEM LAB,BETHESDA,MD 20892.
C3 Brandeis University; Brandeis University; Brandeis University; National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI)
NR 29
TC 262
Z9 294
U1 1
U2 21
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 704
EP 708
DI 
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700094
PM 7990966
DA 2026-03-10
ER

PT J
AU DAVIES, K
AF DAVIES, K
TI RECEPTOR MALFUNCTION
SO NATURE
LA English
DT Article
AB The family of four fibroblast growth factor receptors is stimulating attention with the discovery of genetic defects tying three members to a variety of congenital bone malformations.
NR 9
TC 3
Z9 3
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 202
EP 202
DI 10.1038/372202a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800063
DA 2026-03-10
ER

PT J
AU GOUNNI, AS
   LAMKHIOUED, B
   OCHIAI, K
   TANAKA, Y
   DELAPORTE, E
   CAPRON, A
   KINET, JP
   CAPRON, M
AF GOUNNI, AS
   LAMKHIOUED, B
   OCHIAI, K
   TANAKA, Y
   DELAPORTE, E
   CAPRON, A
   KINET, JP
   CAPRON, M
TI HIGH-AFFINITY IGE RECEPTOR ON EOSINOPHILS IS INVOLVED IN DEFENSE AGAINST PARASITES
SO NATURE
LA English
DT Article
ID epidermal langerhans cells; fc-epsilon-ri; immunoglobulin-e; alpha-subunit; 2nd receptor; chain; gene; resistance; expression; products
AB PARASITIC infections are often associated with eosinophilia and high levels of immunoglobulin E (IgE). This observation has led to speculation that eosinophils and IgE may act together in the immune response against parasites. In support of this hypothesis, IgE and eosinophils participate in cytotoxic reactions directed against Schistosoma mansoni larvae in vitro1,2. Furthermore, epidemiological studies have shown an inverse correlation between levels of specific IgE and rates of infection with Schistosoma3-5. The low-affinity IgE receptor (FcepsilonRII/CD23) was first incriminated in eosinophil activation 6,7. The fact that the high-affinity IgE receptor (FcepsilonRI)8,9 is not only expressed on mast cells and basophils but also on Langerhans cells10,11 led us to investigate the presence of FcepsilonRI on eosinophils. Here we show that FcepsilonRI is expressed on eosinophils from hypereosinophilic patients, is involved in eosinophil degranulation, and participates in eosinophil-mediated cytotoxicity against S. mansoni. Our results indicate that FcepsilonRI may play a major part in immune defence against parasites.
C1 INST PASTEUR, CTR IMMUNOL & BIOL PARASITAIRE,UNITE MIXTE,INSERM, U167,CNRS 624, F-59019 LILLE, FRANCE.
   NIAID, MOLEC ALLERGY & IMMUNOL SECT, BETHESDA, MD 20892 USA.
   CTR HOSP REG UNIV LILLE, SERV DERMATOL A, F-59000 LILLE, FRANCE.
C3 Institut National de la Sante et de la Recherche Medicale (Inserm); Pasteur Network; Universite de Lille; Institut Pasteur Lille; National Institutes of Health (NIH) - USA; NIH National Institute of Allergy & Infectious Diseases (NIAID); Universite de Lille; CHU Lille
NR 23
TC 462
Z9 484
U1 0
U2 3
PU NATURE RESEARCH
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 183
EP 186
DI 10.1038/367183a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000064
PM 8114916
DA 2026-03-10
ER

PT J
AU BARTEL, N
   BIETENHOLZ, MF
   RUPEN, MP
   CONWAY, JE
   BEASLEY, AJ
   SRAMEK, RA
   ROMNEY, JD
   TITUS, MA
   GRAHAM, DA
   ALTUNIN, VI
   JONES, DL
   RIUS, A
   VENTURI, T
   UMANA, G
   FRANCIS, RL
   MCCALL, ML
   RICHER, MG
   STEVENSON, CC
   WEILER, KW
   VANDYK, SD
   PANAGIA, N
   CANNON, WH
   POPELAR, J
   DAVIS, RJ
AF BARTEL, N
   BIETENHOLZ, MF
   RUPEN, MP
   CONWAY, JE
   BEASLEY, AJ
   SRAMEK, RA
   ROMNEY, JD
   TITUS, MA
   GRAHAM, DA
   ALTUNIN, VI
   JONES, DL
   RIUS, A
   VENTURI, T
   UMANA, G
   FRANCIS, RL
   MCCALL, ML
   RICHER, MG
   STEVENSON, CC
   WEILER, KW
   VANDYK, SD
   PANAGIA, N
   CANNON, WH
   POPELAR, J
   DAVIS, RJ
TI THE SHAPE, EXPANSION RATE AND DISTANCE OF SUPERNOVA-1993J FROM VLBI MEASUREMENTS
SO NATURE
LA English
DT Article
ID radio supernovae; young supernova; interferometry; model; m82
AB SUPERNOVA 1993J is one of the closest supernovae discovered this century, allowing observations with very high linear resolution. Radio emission from the supernova became visible within days of the first optical peak, and has remained strong, making this an ideal source for very-long-baseline interferometry (VLBI) investigations1-7. Here we report the results of a series of VLBI observations, made from one to three months after the supernova explosion. We find that the supernova is circularly symmetric, which is somewhat surprising in view of suggestions that the progenitor was a member of a binary system8,9, and the asymmetry implied by optical observations10. The supernova shows no sign of deceleration, and the expansion velocities that we estimate from the VLBI measurements are consistent with the maximum optical line velocities11, suggesting that the radio emission indeed arises from the shock front, where the ejecta are hitting the gas that surrounded the progenitor star. We combine the angular expansion rate determined by the VLBI data with the optically derived expansion speed to estimate a distance to M81 of 4.0 +/- 0.6 Mpc, consistent with the value obtained from measurements of Cepheid variables in M81, 3.63 +/- 0.34 Mpc (ref. 12).
C1 NATL RADIO ASTRON OBSERV,SOCORRO,NM 87801.
   HAYSTACK OBSERV,WESTFORD,MA 01886.
   MAX PLANCK INST RADIOASTRON,D-53010 BONN,GERMANY.
   JET PROP LAB,PASADENA,CA 91109.
   FAC CIENCIAS MATEMAT MADRID,INST ASTRON & GEODESIA,E-28040 MADRID,SPAIN.
   CNR,INST RADIOASTRON,I-40126 BOLOGNA,ITALY.
   CNR,INST RADIOASTRON,NOTO,ITALY.
   USN,RES LAB,WASHINGTON,DC 20375.
   UNIV CALIF BERKELEY,DEPT ASTRON,BERKELEY,CA 94720.
   SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218.
   INST SPACE & TERR SCI,N YORK M3J 3K1,ON,CANADA.
   NAT RESOURCES CANADA,OTTAWA K1A OY3,ON,CANADA.
   NUFFIELD RADIO ASTRON OBSERV LABS,MACCLESFIELD SK11 9DL,CHESHIRE,ENGLAND.
C3 National Radio Astronomy Observatory (NRAO); Max Planck Society; National Aeronautics & Space Administration (NASA); NASA Jet Propulsion Laboratory (JPL); Consejo Superior de Investigaciones Cientificas (CSIC); CSIC-UCM - Instituto de Astronomia y Geodesia (IAG); Istituto Nazionale Astrofisica (INAF); Consiglio Nazionale delle Ricerche (CNR); Consiglio Nazionale delle Ricerche (CNR); United States Department of Defense; United States Navy; United States Naval Research Laboratory; NRL Chesapeake; University of California System; University of California Berkeley; Space Telescope Science Institute; Natural Resources Canada; University of Manchester
RP BARTEL, N (corresponding author), YORK UNIV,DEPT PHYS & ASTRON,N YORK M3J 1P3,ON,CANADA.
NR 32
TC 56
Z9 57
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 610
EP 613
DI 10.1038/368610a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200052
DA 2026-03-10
ER

PT J
AU BOTHERAS, L
AF BOTHERAS, L
TI HEALTH-CARE REFORMS AND THE PHARMACEUTICAL-INDUSTRY
SO NATURE
LA English
DT Article
AB As governments look ever more critically at the costs of drugs, those working in the pharmaceutical industry must become aware of the effects on their own career prospects.
RP BOTHERAS, L (corresponding author), MACMILLAN DAVIES,PHARMACEUT & HEALTHCARE,SALISBURY HOUSE,HERTFORD,HERTS,ENGLAND.
NR 1
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 460
EP 460
DI 10.1038/371460a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500050
PM 8090227
DA 2026-03-10
ER

PT J
AU LUTHI, A
   LAURENT, JP
   FIGUROV, A
   MULLER, D
   SCHACHNER, M
AF LUTHI, A
   LAURENT, JP
   FIGUROV, A
   MULLER, D
   SCHACHNER, M
TI HIPPOCAMPAL LONG-TERM POTENTIATION AND PLEURAL CELL-ADHESION MOLECULES L1 AND NCAM
SO NATURE
LA English
DT Article
ID immunoelectron-microscopic localization; passive-avoidance response; n-cam; neurite outgrowth; mouse cerebellum; memory; consolidation; association; component; membranes
AB SYNAPTIC membranes express cell adhesion molecules(1). Here we investigate the role of the neural cell adhesion molecules L1 and NCAM in hippocampal long-term potentiation (LTP), a sustained-use-dependent increase in synaptic efficacy that has been implicated in learning and memory(2). L1 and NCAM mediate cell interactions during neural development(3) and are strongly expressed in the hippocampus(4,5). They cooperate to strengthen L1-dependent cell adhesion(6-9) and are coupled to second messenger pathways(10-12). We show that LTP in CA1 neurons of rat hippocampal slices was reduced by application of various L1 and NCAM antibodies, recombinant L1 fragments, and upon dissociation of the L1/NCAM complex through oligomannosidic carbohydrates and NCAM peptides. Neither the activation of NMDA (N-methyl-D-aspartate) receptors nor the maintenance of LTP was affected. These results suggest that L1 and NCAM modulate the development or the stabilization of LTP(13).
C1 CTR MED UNIV GENEVA,DEPT PHARMACOL,CH-1211 GENEVA 4,SWITZERLAND.
   ETH ZURICH,DEPT NEUROBIOL,CH-8093 ZURICH,SWITZERLAND.
C3 University of Geneva; Swiss Federal Institutes of Technology Domain; ETH Zurich
RP LUTHI, A (corresponding author), F HOFFMANN LA ROCHE & CO LTD,PRECLIN RES,DIV PHARMA,CH-4002 BASEL,SWITZERLAND.
NR 25
TC 464
Z9 493
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 777
EP 779
DI 10.1038/372777a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200052
PM 7997264
DA 2026-03-10
ER

PT J
AU WEST, MA
   LUCOCQ, JM
   WATTS, C
AF WEST, MA
   LUCOCQ, JM
   WATTS, C
TI ANTIGEN-PROCESSING AND CLASS-II MHC PEPTIDE-LOADING COMPARTMENTS IN HUMAN B-LYMPHOBLASTOID CELLS
SO NATURE
LA English
DT Article
ID receptor-mediated endocytosis; intracellular-transport; invariant chain; late endosm; lymphocytes-b; molecules; transferrin; complex; ph; localization
AB THE peptide/class II major histocompatibility complex (MHC) complexes recognized by CD4(+) T cells have been characterized at the structural(1) and biochemical(2-4) levels and studies on the transport and maturation of class II MHC indicate that specialized sites may be involved in peptide acquisition(5-11). Here we report the characterization of the compartments involved in antigen processing and class II MHC loading relative to distinct functional domains of the endocytic pathway in antigen-specific human B lymphocytes(12-14). Peroxidase-mediated crosslinking analysis(15) in intact cells demonstrates that peptide loading of class II MHC takes place in a compartment accessible to membrane immunoglobulin but not to transferrin receptors, although processing may be initiated within the latter domain. The density of membrane vesicles carrying newly assembled class II MHC complexes was distinct from early and late endosomes and dense lysosomes. Endocytosed antigen-gold complexes enter a class II MHC-rich compartment morphologically very similar to that described previously(9) and within the time frame of biochemically detectable peptide loading.
C1 UNIV BERN,DEPT ANAT,CH-3000 BERN,SWITZERLAND.
C3 University of Bern
RP WEST, MA (corresponding author), UNIV DUNDEE,INST MED SCI,DEPT BIOCHEM,DUNDEE DD1 4HN,SCOTLAND.
FU Wellcome Trust Funding Source: Medline
NR 30
TC 348
Z9 366
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 147
EP 151
DI 10.1038/369147a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100049
PM 8177319
DA 2026-03-10
ER

PT J
AU STAEHLINGHAMPTON, K
   HOFFMANN, FM
   BAYLIES, MK
   RUSHTON, E
   BATE, M
AF STAEHLINGHAMPTON, K
   HOFFMANN, FM
   BAYLIES, MK
   RUSHTON, E
   BATE, M
TI DPP INDUCES MESODERMAL GENE-EXPRESSION IN DROSOPHILA
SO NATURE
LA English
DT Article
ID dorsal ventral axis; germ layers; cell fates; activin-a; box genes; pattern; embryo; induction; homolog; morphogenesis
AB INDUCTIVE interactions between germ layers are an essential feature of the development of many organisms. In several species these interactions are mediated by members of the transforming growth factor-beta (TGF beta) family(1,2). In amphibians, different concentrations of activin can induce different types of mesoderm in the animal cap assay(3-5). In Drosophila, a member of the TGF beta family, decapentaplegic (dpp)(6,7), acts as an inductive signal. Midway through embryogenesis, dpp is expressed in the visceral mesoderm, and enhances the expression of the homeotic gene labial in the underlying midgut endoderm(8,9). Earlier in development, however, dpp expression is limited to the dorsal ectoderm(10). At this stage in development, thickveins, a dpp receptor(11-13), is expressed in the mesoderm(12,13), and this suggests that ectodermal dpp might not only be required for development of dorsal ectoderm(14,15), but could also act inductively to mediate pattern formation in the underlying mesoderm. Here we show, by expressing dpp ectopically in the ectoderm and mesoderm and by examining dpp null mutant embryos, that dpp regulates expression of mesodermal genes.
C1 UNIV CAMBRIDGE,DEPT ZOOL,CAMBRIDGE CB2 3EJ,ENGLAND.
C3 University of Cambridge
RP STAEHLINGHAMPTON, K (corresponding author), UNIV WISCONSIN,MCARDLE LAB CANC RES,1400 UNIV AVE,MADISON,WI 53706, USA.
FU Wellcome Trust Funding Source: Medline
NR 29
TC 177
Z9 198
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 783
EP 786
DI 
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200054
PM 7997266
DA 2026-03-10
ER

PT J
AU GRAINGER, DJ
   KEMP, PR
   LIU, AC
   LAWN, RM
   METCALFE, JC
AF GRAINGER, DJ
   KEMP, PR
   LIU, AC
   LAWN, RM
   METCALFE, JC
TI ACTIVATION OF TRANSFORMING GROWTH-FACTOR-BETA IS INHIBITED IN TRANSGENIC APOLIPOPROTEIN(A) MICE
SO NATURE
LA English
DT Article
ID smooth-muscle cells; expressing human apolipoprotein(a); lipoprotein(a); proliferation; osteopontin; culture; invitro
AB A HIGH concentration of serum lipoprotein(a) is a risk factor for atherosclerosis(1-3). Lipoprotein(a) consists of low-density lipoprotein with the additional protein component, apolipoprotein(a), a homologue of plasminogen(4). Lipoprotein(a) and apolipoprotein(a) enhance proliferation of human vascular smooth muscle cells (hVSMCs) in culture by inhibiting activation of plasminogen to plasmin, thus blocking the proteolytic activation of transforming growth factor-beta (TGF-beta)(5), an autocrine inhibitor of hVSMC proliferation(5,6). The hypothesis that this pathway is a key step in atherogenesis(5) is tested on transgenic mice expressing the human apolipoprotein(a) gene. We show here that the activation of TGF-beta is inhibited in the aortic wall and serum of mice expressing apolipoprotein(a), as a consequence of apolipoprotein(a) inhibition of plasminogen activation. These effects are closely correlated with VSMC activation.
C1 STANFORD UNIV,SCH MED,DIV CARDIOVASC MED,STANFORD,CA 94305.
C3 Stanford University
RP GRAINGER, DJ (corresponding author), UNIV CAMBRIDGE,DEPT BIOCHEM,TENNIS COURT RD,CAMBRIDGE CB2 1QW,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 21
TC 343
Z9 369
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 460
EP 462
DI 10.1038/370460a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700056
PM 8047165
DA 2026-03-10
ER

PT J
AU NICHOLS, GT
   WYLLIE, PJ
   STERN, CR
AF NICHOLS, GT
   WYLLIE, PJ
   STERN, CR
TI SUBDUCTION ZONE-MELTING OF PELAGIC SEDIMENTS CONSTRAINED BY MELTING EXPERIMENTS
SO NATURE
LA English
DT Article
ID upper mantle; geological applications; phase-relationships; volcanic-rocks; 35 kilobars; arc magmas; water; isotopes; system
AB THE fate of pelagic sediments in subduction zones has an important bearing on global geochemical cycles and the thermal structure of subduction zones. Recent mass-balance calculations(1) have indicated that about 20% of subducted sediments are recycled to volcanic arcs. Trace-element studies(2) of these volcanic arcs imply that the subducted sediment melts while the gabbroic crust that underlies it dehydrates. This requires a rather specific thermal structure in subduction zones. Here we report laboratory melting experiments that allow us to derive melting curves for pelagic red clay at pressures of up to 40 kbar, equivalent to depths of 120 km within the mantle. The melting behaviour of wet red clay is similar to that for wet gabbro, but melting occurs at a slightly tower temperature, showing that sediment melting and gabbro dehydration can occur at the same temperature. The combination of trace-element data and phase diagrams such as that derived here mag thus be used to constrain the temperature of the slab-mantle boundary.
C1 UNIV COLORADO,DEPT GEOL SCI,BOULDER,CO 80309.
C3 University of Colorado System; University of Colorado Boulder
RP NICHOLS, GT (corresponding author), CALTECH,DIV GEOL & PLANETARY SCI,MAIL CODE 170-25,PASADENA,CA 91125, USA.
NR 40
TC 225
Z9 249
U1 1
U2 50
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 785
EP 788
DI 10.1038/371785a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800055
DA 2026-03-10
ER

PT J
AU DUBA, A
   HEIKAMP, S
   MEURER, W
   NOVER, G
   WILL, G
AF DUBA, A
   HEIKAMP, S
   MEURER, W
   NOVER, G
   WILL, G
TI EVIDENCE FROM BOREHOLE SAMPLES FOR THE ROLE OF ACCESSORY MINERALS IN LOWER-CRUSTAL CONDUCTIVITY
SO NATURE
LA English
DT Article
ID electrical-conductivity; rocks; carbon
AB THE high electrical conductivity of the lower continental crust, as inferred from geophysical measurements1, has defied a simple explanation. Both pore-saturating brines2 and interconnected carbon films3-5 have been proposed as conducting pathways, but their relative importance remains uncertain, and may vary from place to place6. So far, attempts to address this question in the laboratory have had to rely on samples of metamorphic rock collected from surface exposures7-10.  Although these rocks almost certainly originated in the lower crust, chemical alteration during their transport to, and residence at, the surface is likely to have affected their conducting properties. Here we report conductivity data for pristine crustal rocks recovered from depths of up to 4.6 km in the KTB boreholes in southern Germany. Our results show that the electrical conductivity of accessory phases such as Fe-Ti oxides and sulphides can enhance, or even surpass, the high conductivity produced by saline fluids.
C1 UNIV BONN,INST MINERAL,W-5300 BONN,GERMANY.
C3 University of Bonn
RP DUBA, A (corresponding author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA.
NR 18
TC 92
Z9 98
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 59
EP 61
DI 10.1038/367059a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500057
DA 2026-03-10
ER

PT J
AU ZHENG, B
   XUE, W
   KELSOE, G
AF ZHENG, B
   XUE, W
   KELSOE, G
TI LOCUS-SPECIFIC SOMATIC HYPERMUTATION IN GERMINAL CENTER T-CELLS
SO NATURE
LA English
DT Article
ID immunoglobulin genes; antigen receptor; immune-response; chain genes; mutation; generation; sequences; centers; memory; dna
AB SOMATIC hypermutation and affinity-driven selection of active immunoglobulin genes occur in germinal centres (GCs), resulting in the generation of high-affinity memory B cells(1-3). In contrast, T lymphocytes do not require the germinal centre microenvironment to establish memory and the T-cell antigen receptor (TCR) genes, though homologous to immunoglobulin genes, are believed to be incapable of hypermutation(5-7). Here we present direct evidence that the small population of antigen-specific T cells that are recruited into splenic GCs acquire mutations in the variable region of genes encoding TCR alpha-chains (V alpha) but not those of beta-chains. These locus-specific mutations reach frequencies comparable to mutated inmunoglobulin V-H exons recovered from the same site and exhibit similar substitution biases and DNA strand polarity. T cells bearing identical mutations appear in multiple GCs, raising the possibility that some cells bearing mutant TCRs may re-enter the peripheral lymphocyte pool.
RP ZHENG, B (corresponding author), UNIV MARYLAND,SCH MED,DEPT MICROBIOL & IMMUNOL,655 W BALTIMORE ST,BALTIMORE,MD 21201, USA.
NR 30
TC 118
Z9 126
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 556
EP 559
DI 10.1038/372556a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200054
PM 7990929
DA 2026-03-10
ER

PT J
AU DESAUVAGE, FJ
   HASS, PE
   SPENCER, SD
   MALLOY, BE
   GURNEY, AL
   SPENCER, SA
   DARBONNE, WC
   HENZEL, WJ
   WONG, SC
   KUANG, WJ
   OLES, KJ
   HULTGREN, B
   SOLBERG, LA
   GOEDDEL, DV
   EATON, DL
AF DESAUVAGE, FJ
   HASS, PE
   SPENCER, SD
   MALLOY, BE
   GURNEY, AL
   SPENCER, SA
   DARBONNE, WC
   HENZEL, WJ
   WONG, SC
   KUANG, WJ
   OLES, KJ
   HULTGREN, B
   SOLBERG, LA
   GOEDDEL, DV
   EATON, DL
TI STIMULATION OF MEGAKARYOCYTOPOIESIS AND THROMBOPOIESIS BY THE C-MPL LIGAND
SO NATURE
LA English
DT Article
ID factor receptor superfamily; rebound-thrombocytosis; partial-purification; human erythropoietin; colony formation; messenger-rna; gm-csf; invitro; sequence; invivo
AB Physiological platelet synthesis is thought to require the humoral activities of meg-CSF and thrombopoietin, which respectively promote proliferation and maturation of megakaryocytic cells. A meg-CSF/thrombopoietin-like protein that is present in plasma of irradiated pigs has been purified and cloned. This protein binds to and activates the c-mpl protein, a member of the cytokine receptor superfamily. The isolated Mpl ligand shares homology with erythropoietin and stimulates both megakaryocytopoiesis and thrombopoiesis.
C1 MAYO CLIN, DIV HEMATOL ONCOL, JACKSONVILLE, FL 32224 USA.
   GENENTECH INC, DEPT MOLEC BIOL, San Francisco, CA 94080 USA.
   GENENTECH INC, DEPT CARDIOVASC RES, San Francisco, CA 94080 USA.
   GENENTECH INC, DEPT PROT CHEM, San Francisco, CA 94080 USA.
   MAYO CLIN & MAYO FDN, DIV HEMATOL ONCOL, ROCHESTER, MN 55905 USA.
C3 Mayo Clinic; Roche Holding; Roche Holding USA; Genentech; Roche Holding; Genentech; Roche Holding USA; Roche Holding; Roche Holding USA; Genentech; Mayo Clinic
NR 48
TC 1208
Z9 1348
U1 1
U2 31
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 533
EP 538
DI 10.1038/369533a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400040
PM 8202154
DA 2026-03-10
ER

PT J
AU ZECH, D
   KELLER, H
   CONDER, K
   KALDIS, E
   LIAROKAPIS, E
   POULAKIS, N
   MULLER, KA
AF ZECH, D
   KELLER, H
   CONDER, K
   KALDIS, E
   LIAROKAPIS, E
   POULAKIS, N
   MULLER, KA
TI SITE-SELECTIVE OXYGEN-ISOTOPE EFFECT, IN OPTIMALLY DOPED YBA2CU3O6+X
SO NATURE
LA English
DT Article
ID high-tc superconductors; high-temperature superconductivity; ba-cu-o; shift; la2-xsrxcuo4; substitution
AB IN CONVENTIONAL superconductors, the large dependence of the superconducting transition temperature (T-c) on the isotope mass (T-c proportional to m(-alpha), with alpha approximate to 0.5) gives strong evidence for electron pairing by a phonon-mediated mechanism. The copper oxide superconductors, on the other hand, exhibit a small oxygen isotope effect (alpha approximate to 0.02; see, for example, refs 1-14), suggesting a mechanism more complex than simple phonon-mediated pairing(15). To obtain further insight into this mechanism, it is important to determine the contribution from different oxygen sites in the crystal lattice to the total oxygen isotope effect. Recently, a negative isotope effect associated with oxygen atoms in the copper oxide planes of the crystal structure was reported(13) for highly doped YBa2Cu3O6+x, implying that the apical/chain oxygens make a substantial contribution to the total oxygen isotope shift. Here we investigate this effect in optimally doped YBa2Cu3O6+x, by measuring separately the contributions to the total isotope shift of the planar and apical/chain oxygen sites. The sum of the site-selective isotope shifts equals that of the total measured shift, illustrating the self-consistency of our results. In contrast to the previous Work(13), we find that more than 80% of the total (positive) isotope effect is associated with the copper oxide planes.
C1 ETH ZURICH,FESTKORPERPHYS LAB,CH-8093 ZURICH,SWITZERLAND.
   NATL TECH UNIV ATHENS,DEPT PHYS,GR-15780 ATHENS,GREECE.
C3 Swiss Federal Institutes of Technology Domain; ETH Zurich; National Technical University of Athens
RP ZECH, D (corresponding author), UNIV ZURICH,INST PHYS,CH-8057 ZURICH,SWITZERLAND.
NR 26
TC 128
Z9 132
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 681
EP 683
DI 10.1038/371681a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300048
DA 2026-03-10
ER

PT J
AU HUANG, MX
   CHALFIE, M
AF HUANG, MX
   CHALFIE, M
TI GENE INTERACTIONS AFFECTING MECHANOSENSORY TRANSDUCTION IN CAENORHABDITIS-ELEGANS
SO NATURE
LA English
DT Article
ID sodium-channel; expression; neurons; protein
AB GENETIC screening has identified a group of mec (mechanosensory) genes that are required for the function of a set of six touch-receptor neurons in the nematode Caenorhabditis elegans1,2. Such genes potentially encode components of the mechanosensory apparatus. We have cloned one of these genes, mec-10, which is a member of the degenerin gene family (genes such as mec-4 and deg-1 (refs 3, 4) that can be mutated to cause neurodegeneration). Because components of an amiloride-sensitive sodium channel (alpha, beta and gammarENaC) from rat6-8 share considerable sequence similarity with the C. elegans genes, it is likely that degenerins may function as channel proteins. Here we show that two degenerin homologues (mec-4 and mec-10) are expressed in the same cells, although each provides a unique function. Based on genetic data of mutations affecting mec-10-induced degeneration, we propose that the products of three genes (mec-4, mec-10 and mec-6) form a complex needed for mechanosensation, and that several other mec genes may be important in regulating the putative channel complex.
RP HUANG, MX (corresponding author), COLUMBIA UNIV,DEPT BIOL SCI,1012 FAIRCHILD CTR,NEW YORK,NY 10027, USA.
NR 24
TC 351
Z9 421
U1 0
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 467
EP 470
DI 10.1038/367467a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900056
PM 7509039
DA 2026-03-10
ER

PT J
AU PETRIE, M
AF PETRIE, M
TI IMPROVED GROWTH AND SURVIVAL OF OFFSPRING OF PEACOCKS WITH MORE ELABORATE TRAINS
SO NATURE
LA English
DT Article
ID costly mate preferences; evolution
AB THERE is considerable controversy about what females gain from mate choice in a lekking species in which males provide no obvious resources. Females may gain direct benefits such as safe copulations or increased fertility by mating with particular males, or they may gain indirect benefits for their offspring(1-3). It is difficult to look for paternal effects on offspring performance because it is hard to control for any differences in the material and genetic contribution provided by the female and in the environment of the offspring during development; previous experiments have controlled for rearing environment but not maternal effects(4). Here I report results from a controlled breeding experiment, with females allocated to males at random and all offspring reared under the same conditions, which show that the offspring of successful lek peacocks (Pavo cristatus) with the most elaborate trains grow and survive better under nearly natural conditions.
RP PETRIE, M (corresponding author), UNIV OXFORD,DEPT ZOOL,S PARKS RD,OXFORD OX1 3PS,ENGLAND.
NR 10
TC 369
Z9 415
U1 2
U2 193
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 598
EP 599
DI 10.1038/371598a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900049
DA 2026-03-10
ER

PT J
AU RIDDIHOUGH, G
AF RIDDIHOUGH, G
TI THE ART OF INTERCALATION
SO NATURE
LA English
DT Article
NR 8
TC 1
Z9 1
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 488
EP 488
DI 10.1038/367488a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900062
DA 2026-03-10
ER

PT J
AU SOMERS, W
   ULTSCH, M
   DEVOS, AM
   KOSSIAKOFF, AA
AF SOMERS, W
   ULTSCH, M
   DEVOS, AM
   KOSSIAKOFF, AA
TI THE X-RAY STRUCTURE OF A GROWTH-HORMONE PROLACTIN RECEPTOR COMPLEX
SO NATURE
LA English
DT Article
ID extracellular domain; binding determinants; rational design; dimerization; superfamily; antagonists; refinement; variants; crystals; detector
AB THE human pituitary hormones, growth hormone (hGH) and prolactin (hPRL), regulate a large variety of physiological processes, among which are growth and differentiation of muscle, bone and cartilage cells, and lactation(1). These activities are initiated by hormone-receptor binding. The hGH and hPRL receptors (hGH(R) and hPRL(R), respectively) are single-pass transmembrane receptors from class 1 of the haematopoietic receptor superfamily(2,3). This classification is based on sequence similarity in their extracellular domains, notably a highly conserved pentapeptide, the so-called 'WSXWS box', the function of which is controversial. All ligands in class 1 activate their respective receptors by clustering mechanisms(4). In the case of hGH, activation involves receptor homodimerization in a sequential process: the active ternary complex containing one ligand and two receptor molecules is formed by association of a receptor molecule to an intermediate 1:1 complex(5-8). hPRL does not bind to the hGH receptor, but hGH binds to both the hGH(R) and hPRL(R), and mutagenesis studies have shown that the receptor-binding sites on hGH overlap(9). We present here the crystal structure of the 1:1 complex of hGH bound to the extracellular domain of the hPRL(R). Comparisons with the hGH-hGH(R) complex(10) reveal how hGH can bind to the two distinctly different receptor binding surfaces.
C1 GENENTECH INC,DEPT PROT ENGN,S SAN FRANCISCO,CA 94080.
C3 Roche Holding; Genentech; Roche Holding USA
NR 24
TC 347
Z9 389
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 478
EP 481
DI 10.1038/372478a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200061
PM 7984244
DA 2026-03-10
ER

PT J
AU SOLEM, JC
AF SOLEM, JC
TI DENSITY AND SIZE OF COMET SHOEMAKER-LEVY-9 DEDUCED FROM A TIDAL BREAKUP MODEL
SO NATURE
LA English
DT Article
AB Although comets have been studied throughout most of recorded history, a detailed understanding of their internal properties is still lacking. Recent observations' of the split comet Shoemaker-Levy 9-actually a spectacular string of cometary fragments that resulted from the tidal disruption of a single parent body as it passed close to Jupiter(2-5)-have therefore stimulated much interest, as they provide an unprecedented opportunity to Investigate the physical properties of comets more generally(6-8). I report here simulations of the tidal breakup of the parent comet, which I assume to have been an assemblage of a large number of spherical components bound together only by gravity. Following the initial tidal disruption of the assemblage, the particles coalesce rapidly by mutual gravitation into a chain of larger fragments, the morphology of which depends critically on the density of the components. By comparing the size, number and distribution of the stimulated fragments with observations of Shoemaker-Levy 9, I determine an average comet density of about 0.5 g cm(-3) and a parent comet diameter of about 1.8 km.
RP SOLEM, JC (corresponding author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA.
NR 16
TC 58
Z9 61
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 349
EP 351
DI 10.1038/370349a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400048
DA 2026-03-10
ER

PT J
AU FISHER, PJ
   PRENDERGAST, FG
   EHRHARDT, MR
   URBAUER, JL
   WAND, AJ
   SEDAROUS, SS
   MCCORMICK, DJ
   BUCKLEY, PJ
AF FISHER, PJ
   PRENDERGAST, FG
   EHRHARDT, MR
   URBAUER, JL
   WAND, AJ
   SEDAROUS, SS
   MCCORMICK, DJ
   BUCKLEY, PJ
TI CALMODULIN INTERACTS WITH AMPHIPHILIC PEPTIDES COMPOSED OF ALL D-AMINO ACIDS
SO NATURE
LA English
DT Article
ID light-chain kinase; multidimensional nmr; complex-formation; binding domain; proteins; melittin; recognition; sequence; spectra; enzyme
AB CALMODULIN binds to amphiphilic, helical peptides of a variety of amino-acid sequences1-8. These peptides are usually positively charged, although there is spectroscopic evidence that at least one neutral peptide binds5. The complex between calmodulin and one of its natural target peptides, the binding site for calmodulin on smooth muscle myosin light-chain kinase (RS20)9, has been investigated by crystallography10 and NMR11-13 which have characterized the interactions between the ligand and the protein. From these data, it appears that the calmodulin-binding surface is sterically malleable and van der Waals forces probably dominate the binding. To explore further this apparently permissive binding, we investigated the chiral selectivity of calmodulin using synthesized analogues of melittin and RS20 that consisted of only D-amino acids. Fluorescence and NMR measurements show that D-melittin and D-RS20 both bind avidly to calmodulin, probably in the same general binding site as that for peptides having all L-amino acids. The calmodulin-peptide binding surface is therefore remarkably tolerant sterically. Our results suggest a potentially useful approach to the design of non-hydrolysable or slowly hydrolysable intracellular inhibitors of calmodulin.
C1 MAYO CLIN & MAYO FDN,DEPT PHARMACOL,200 1ST ST SW,ROCHESTER,MN 55905.
   MAYO CLIN & MAYO FDN,DEPT BIOCHEM & MOLEC BIOL,ROCHESTER,MN 55905.
   UNIV ILLINOIS,SCH CHEM SCI,DEPT BIOCHEM,URBANA,IL 61801.
C3 Mayo Clinic; Mayo Clinic; University of Illinois System; University of Illinois Urbana-Champaign
NR 28
TC 61
Z9 68
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 651
EP 653
DI 10.1038/368651a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200065
PM 8145853
DA 2026-03-10
ER

PT J
AU HE, ZJJ
   NAKAYAMA, K
AF HE, ZJJ
   NAKAYAMA, K
TI APPARENT MOTION DETERMINED BY SURFACE LAYOUT NOT BY DISPARITY OR 3-DIMENSIONAL DISTANCE
SO NATURE
LA English
DT Article
ID representation; paths
AB THE most meaningful events ecologically, including the motion of objects, occur in relation to or on surfaces1. We run along the ground, cars travel on roads, balls roll across lawns, and so on. Even though there are other motions, such as flying of birds, it is likely that motion along surfaces is more frequent and more significant biologically. To examine whether events occurring in relation to surfaces have a preferred status in terms of visual representation, we asked whether the phenomenon of apparent motion would show a preference for motion attached to surfaces. We used a competitive three-dimensional motion paradigm2 and found that there is a preference to see motion between tokens placed within the same disparity as opposed to different planes. Supporting our surface-layout hypothesis, the effect of disparity was eliminated either by slanting the tokens so that they were all seen within the same surface plane or by inserting a single slanted background surface upon which the tokens could rest. Additionally, a highly curved stereoscopic surface led to the perception of a more circuitous motion path defined by that surface, instead of the shortest path in three-dimensional space.
RP HE, ZJJ (corresponding author), HARVARD UNIV,DEPT PSYCHOL,VIS SCI LAB,33 KIRKLAND ST,CAMBRIDGE,MA 02138, USA.
NR 13
TC 49
Z9 55
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 173
EP 175
DI 10.1038/367173a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000061
PM 8114913
DA 2026-03-10
ER

PT J
AU HOFMANN, P
   SCHINDLER, KM
   BAO, S
   BRADSHAW, AM
   WOODRUFF, DP
AF HOFMANN, P
   SCHINDLER, KM
   BAO, S
   BRADSHAW, AM
   WOODRUFF, DP
TI DIRECT IDENTIFICATION OF ATOMIC AND MOLECULAR ADSORPTION SITES USING PHOTOELECTRON DIFFRACTION
SO NATURE
LA English
DT Article
ID holography
AB THE determination of the adsorption geometry of molecules and molecular fragments on single-crystal metal surfaces is central to our understanding of heterogeneous catalysis. Adsorbate structures can be determined precisely by techniques such as low-energy electron diffraction and photoelectron diffraction. Such methods suffer, however, from the rather inefficient approach to data analysis: the diffracted intensities are compared with simulated data for a trial structure, which is successively modified by trial and error until good agreement is achieved. Following a suggestion by Barton that a photoelectron angular distribution may be regarded as a photoelectron hologram(1,2), attention has been focused recently on simpler methods for adsorbate structure determination which give real-space information directly(3-7). We demonstrate here a direct method for determining both the adsorption site and the adsorbate-substrate separation from photoelectron diffraction datas. We illustrate the method using two adsorption systems: CO on Cu(110) and OCH3 on Cu(111). Our results are consistent with those determined for the same systems by a related method(7), which requires a considerably larger data set and provides bond lengths at lower precision. For adsorbates on simple surfaces, we therefore propose that our approach provides an accurate and easily implemented method for structure determination.
C1 UNIV WARWICK,DEPT PHYS,COVENTRY CV4 7AL,W MIDLANDS,ENGLAND.
C3 University of Warwick
RP HOFMANN, P (corresponding author), MAX PLANCK GESELL,FRITZ HABER INST,FARADAYWEG 4-6,D-14195 BERLIN,GERMANY.
NR 16
TC 90
Z9 92
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 131
EP 132
DI 10.1038/368131a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000060
DA 2026-03-10
ER

PT J
AU ERICKSON, SL
   DESAUVAGE, FJ
   KIKLY, K
   CARVERMOORE, K
   PITTSMEEK, S
   GILLETT, N
   SHEEHAN, KCF
   SCHREIBER, RD
   GOEDDEL, DV
   MOORE, MW
AF ERICKSON, SL
   DESAUVAGE, FJ
   KIKLY, K
   CARVERMOORE, K
   PITTSMEEK, S
   GILLETT, N
   SHEEHAN, KCF
   SCHREIBER, RD
   GOEDDEL, DV
   MOORE, MW
TI DECREASED SENSITIVITY TO TUMOR-NECROSIS-FACTOR BUT NORMAL T-CELL DEVELOPMENT IN TNF RECEPTOR-2-DEFICIENT MICE
SO NATURE
LA English
DT Article
ID factor receptor; monoclonal-antibody; endotoxic-shock; monocytogenes; resistant; infection; binding; domain; lines
AB TUMOUR necrosis factor (TNF) elicits multiple biological effects through two distinct cell surface receptors, TNF-R1 (p55) and TNF-R2 (p75). Most TNF-mediated biological responses, such as cell death, gene induction, antiviral activity and cytokine production, have been attributed to TNF-R1 (refs 1-5). Gene targeting of this receptor confirms its role in the lethality attributable to low doses of lipopolysaccharide after sensitization with D-galactosamine(6,7); surprisingly, the toxicity of high doses of lipopolysaccharide was unaffected. The function of TNF-R2 is less well understood, although there are data supporting a role in T-cell development and the proliferation of cytotoxic T lymphocytes(8,9). To clarify the physiological role of TNF-R2, we have generated mice deficient in this receptor by gene targeting. The TNF-R2(-/-) mice show normal T-cell development and activity, but we find that they have increased resistance to TNF-induced death. Additionally, such mice injected subcutaneously with TNF show a dramatic decrease in tissue necrosis, indicating that this receptor plays a role in the necrotic effects of TNF.
C1 GENENTECH INC,DEPT CELL GENET,S SAN FRANCISCO,CA 94080.
   GENENTECH INC,DEPT MOLEC BIOL,S SAN FRANCISCO,CA 94080.
   GENENTECH INC,DEPT ENDOCRINE RES & PHARMACOL,S SAN FRANCISCO,CA 94080.
   WASHINGTON UNIV,SCH MED,CTR IMMUNOL,DEPT PATHOL,ST LOUIS,MO 63110.
C3 Roche Holding; Roche Holding USA; Genentech; Roche Holding; Genentech; Roche Holding USA; Roche Holding; Genentech; Roche Holding USA; Washington University (WUSTL)
NR 22
TC 549
Z9 580
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 560
EP 563
DI 10.1038/372560a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200055
PM 7990930
DA 2026-03-10
ER

PT J
AU MCPHERSON, A
   THOMPSON, BD
   BORISOV, AB
   BOYER, K
   RHODES, CK
AF MCPHERSON, A
   THOMPSON, BD
   BORISOV, AB
   BOYER, K
   RHODES, CK
TI MULTIPHOTON-INDUCED X-RAY-EMISSION AT 4-5 KEV FROM XE ATOMS WITH MULTIPLE CORE VACANCIES
SO NATURE
LA English
DT Article
ID laser
AB SEVERAL recent experimental findings(1-3) have pointed to a possible route for making an X-ray laser, which could in principle provide an imaging system capable of molecular resolution(4). The method involves the multiphoton excitation of atmos in van der Waals clusters or in molecules to yield ions with core-electron vacancies(1,2),then decay by emission of X-rays, in conjunction with a self-chanelling propagation mode of electromagnetic radiation(3). The multiphoton excitation may be stimulated by ultrahigh-brightness, subpicosecond pulses of laser light(5). We have previously observed(2) emission of X-rays from L-shell transitions in core-excited krypton atmos using this approach. Here we report the multiphoton production of X-rays of wavelength 2-3 Angstrom from highly ionized xenon atmos which possess a large number of inner-shell vacancies while retaining several electrons in relatively weakly bound outer orbitals. Atoms with this 'inverted' electronic configuration are designated 'hollow atmos'(6,7). We find that generation of hollow atmos can become the dominant excitation mode for such systems, making their exploitation in an X-ray laser a real possibility.
RP MCPHERSON, A (corresponding author), UNIV ILLINOIS,DEPT PHYS M-C 273,845 W TAYLOR ST,CHICAGO,IL 60607, USA.
NR 14
TC 424
Z9 441
U1 1
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 631
EP 634
DI 10.1038/370631a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000043
DA 2026-03-10
ER

PT J
AU HERSCHBACH, BM
   ARNAUD, MB
   JOHNSON, AD
AF HERSCHBACH, BM
   ARNAUD, MB
   JOHNSON, AD
TI TRANSCRIPTIONAL REPRESSION DIRECTED BY THE YEAST ALPHA-2 PROTEIN IN-VITRO
SO NATURE
LA English
DT Article
ID mating-type locus; saccharomyces-cerevisiae; polymerase-ii; activation; drosophila; binds; nucleosm; operator; complex; domain
AB THE alpha 2 protein, a homeodomain protein involved in specifying cell type in the budding yeast Saccharomyces cerevisiae, is a transcriptional repressor(1,2). alpha 2 binds cooperatively with Mcm1, a serum response factor-related protein, to the a-specific gene operator(3-6). The alpha 2-Mcm1 complex in turn recruits Ssn6 and Tup1 to the operator, and we believe that these latter two proteins are responsible for the transcriptional repression(7-9). Placement of the a-specific gene operator in any of a variety of positions upstream of a test promoter leads to repression of that promoter in vivo(9-11). In this respect, the a-specific gene operator resembles a negatively acting enhancer. Here we describe the in vitro reconstitution of this example of negative control from a distance. We observe repression in vitro in the absence of exogenously added activator protein and on templates that lack binding sites for known activator proteins, and we infer that alpha 2-directed repression acts on the general transcription machinery.
C1 UNIV CALIF SAN FRANCISCO,DEPT MICROBIOL & IMMUNOL,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco
RP HERSCHBACH, BM (corresponding author), UNIV CALIF SAN FRANCISCO,DEPT BIOCHEM & BIOPHYS,SAN FRANCISCO,CA 94143, USA.
NR 30
TC 100
Z9 106
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 309
EP 311
DI 10.1038/370309a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900069
PM 8035881
DA 2026-03-10
ER

PT J
AU YEH, H
   LIU, P
   BRIGGS, M
   SYNOLAKIS, C
AF YEH, H
   LIU, P
   BRIGGS, M
   SYNOLAKIS, C
TI PROPAGATION AND AMPLIFICATION OF TSUNAMIS AT COASTAL BOUNDARIES
SO NATURE
LA English
DT Article
ID island
AB WHEN tsunamis hit a coastal area, they often cause substantial damage and loss of life at locations otherwise well protected from normal (even severe) wind-generated waves. An example of such a catastrophe took place on 12 December 1992, when an earthquake of magnitude M(s) = 7.5 occurred in the eastern region of Flores Island, Indonesia(1,2). One of the areas hardest hit by the resulting tsunamis was Babi, a small coastal island; two villages on the island were completely destroyed, even though both were located in sheltered areas where wave conditions air normally calm. Here we describe the results of numerical and laboratory experiments that show how, unlike wind-generated waves, tsunamis are capable of penetrating into sheltered coastal areas without significantly losing their energy. For the case of Babi Island, the original tsunami wave,vas split into two, with one wave propagating around each side of the island. The two waves met in the sheltered region, and the subsequent amplification of wave amplitude resulted in the destructive flow onto the beach.
C1 CORNELL UNIV,ITHACA,NY 14853.
   USA,CORPS ENGINEERS,WATERWAYS EXPT STN,VICKSBURG,MS 39180.
   UNIV SO CALIF,LOS ANGELES,CA 90089.
C3 Cornell University; United States Department of Defense; United States Army; U.S. Army Corps of Engineers; U.S. Army Engineer Research & Development Center (ERDC); University of Southern California
RP YEH, H (corresponding author), UNIV WASHINGTON,DEPT CIVIL ENGN,FX-10,SEATTLE,WA 98195, USA.
NR 10
TC 110
Z9 124
U1 0
U2 23
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 353
EP 355
DI 10.1038/372353a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700052
DA 2026-03-10
ER

PT J
AU COLLINGHAM, D
AF COLLINGHAM, D
TI FUTURE OF THE EUROSCIENTIST
SO NATURE
LA English
DT Article
AB Labour mobility within the pharmaceutical and biotech sectors in Europe is becoming a crucial issue to both employers and employees.
RP COLLINGHAM, D (corresponding author), RUSTON POOLE INT,11-12 BUCKINGHAM GATE,LONDON SW1E 6LB,ENGLAND.
NR 3
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 724
EP 724
DI 10.1038/371724a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300063
PM 7935821
DA 2026-03-10
ER

PT J
AU BORTOLOTTO, ZA
   BASHIR, ZI
   DAVIES, CH
   COLLINGRIDGE, GL
AF BORTOLOTTO, ZA
   BASHIR, ZI
   DAVIES, CH
   COLLINGRIDGE, GL
TI A MOLECULAR SWITCH ACTIVATED BY METABOTROPIC GLUTAMATE RECEPTORS REGULATES INDUCTION OF LONG-TERM POTENTIATION
SO NATURE
LA English
DT Article
ID rat hippocampus; area ca1; stimulation; depression; neurons
AB PHARMACOLOGICAL studies of long-term potentiation (LTP) in the hippocampus are starting to provide a molecular understanding of synaptic plastic processes which are believed to be important for learning and memory in vertebrates(1). In the CA1 region of the hippocampus, the synaptic activation of glutamate receptors of the N-methyl-D-aspartate (NMDA) subtype is necessary for the induction of LTP under most experimental conditions(2,3). The synaptic activation of metabotropic glutamate receptors (mGluRs) is also needed for the induction of LTP(4,5). We now show that the role of mGluRs in the induction of LTP is fundamentally different from that of NMDA receptors. NMDA receptors initiate a molecular event that needs to be triggered each time a tetanus is delivered to induce LTP. In contrast, mGluRs activate a molecular switch which then negates the need for mGluR stimulation during the induction of LTP. This mGluR-activated switch is input-specific and can be turned off by a train of low-frequency stimulation. The molecular switch is a new feature of LTP which has fundamental consequences for our understanding of synaptic plastic mechanisms.
RP BORTOLOTTO, ZA (corresponding author), UNIV BIRMINGHAM,SCH MED,DEPT PHARMACOL,BIRMINGHAM B15 2TT,ENGLAND.
NR 18
TC 339
Z9 387
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 740
EP 743
DI 10.1038/368740a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300058
PM 8152485
DA 2026-03-10
ER

PT J
AU LI, T
   NICOLAOU, KC
AF LI, T
   NICOLAOU, KC
TI CHEMICAL SELF-REPLICATION OF PALINDROMIC DUPLEX DNA
SO NATURE
LA English
DT Article
ID template-directed synthesis; triple-helix; hexadeoxynucleotide; systems; linkage
AB MOLECULAR replication, a fundamental process of life, has in recent years been the subject of laboratory investigations using simple chemical systems(1-10). Whereas the work of Rebek's group(4,5) has focused on molecular architectures not known in living systems, self-replicating and template-based self-assembling systems based on nucleotides(6-8) are regarded as potential models for exploring the evolution of replicating systems on the early Earth. Previous replicating oligonucleotides have been of the single-stranded, self-complementary type: small oligonucleotide fragments are assembled on a pre-existing template and linked to form an exact copy of the template. This process cannot easily be reiterated, however, because of the strong binding of the newly formed strand to the original template. Furthermore, DNA replication in living systems operates by complementarity rather than self-complementarity-each newly assembled strand is complementary to, rather than identical to, its template-and the replication process starts and finishes with double helices. Here we report the self-replication of palindromic (symmetrical) duplex DNA-like oligonucleotides, 24 monomers long, in the absence of enzymes by means of a cycle that transfers information from template to copy and is potentially capable of extension to include non-symmetrical sequences, selection and mutation. Replication proceeds by a chemical process involving the formation of an intermediate triplex structure, and is sequence-selective in the sense that mismatches impair its efficiency. These results indicate that DNA-like double-helical molecules can replicate without assistance from proteins, a finding that may be relevant both to the appearance of replicating systems on the early Earth and to the development of new approaches to DNA amplification.
C1 Scripps Res Inst, DEPT CHEM, LA JOLLA, CA 92037 USA.
   UNIV CALIF SAN DIEGO, DEPT CHEM, LA JOLLA, CA 92093 USA.
C3 Scripps Research Institute; University of California System; University of California San Diego
NR 23
TC 183
Z9 197
U1 0
U2 32
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 218
EP 221
DI 10.1038/369218a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700051
PM 8183341
DA 2026-03-10
ER

PT J
AU THOUVENY, N
   DEBEAULIEU, JL
   BONIFAY, E
   CREER, KM
   GUIOT, J
   ICOLE, M
   JOHNSEN, S
   JOUZEL, J
   REILLE, M
   WILLIAMS, T
   WILLIAMSON, D
AF THOUVENY, N
   DEBEAULIEU, JL
   BONIFAY, E
   CREER, KM
   GUIOT, J
   ICOLE, M
   JOHNSEN, S
   JOUZEL, J
   REILLE, M
   WILLIAMS, T
   WILLIAMSON, D
TI CLIMATE VARIATIONS IN EUROPE OVER THE PAST 140-KYR DEDUCED FROM ROCK MAGNETISM
SO NATURE
LA English
DT Article
ID lacustrine organic sedimentation; lac-du-bouchet; greenland ice; pollen analysis; chinese loess; haute-loire; france; record; pleistocene; core
AB RAPID shifts in climate during the last glacial are now well documented, particularly from the oxygen isotope records of the two Greenland ice cores GRIP(1,2) and GISP2(3). In the GRIP record(1,2) these climate events are also seen during the preceding (Eemian) interglacial which may be an analogue for the future climate, warmed by the greenhouse effect. But these shifts are not found in the Eemian section of the GISP2 core(3) casting doubt on whether the rapid shifts in the GRIP oxygen isotope record really do represent a climate signal. Here we present magnetic susceptibility, pollen and organic carbon records from maar lake deposits in the Massif Central, France. These data provide an independent record of past climate and we find that they correlate well with the ice-core records during the last glacial. During the Eemian, two rapid cooling events seen in our record also correlate with those seen in the GRIP ice core, supporting the idea that rapid climate change did occur in the Eemian interglacial and demonstrating that it extended to continental Europe.
C1 LAB BOT HIST & PALYNOL,F-13397 MARSEILLE 20,FRANCE.
   UNIV EDINBURGH,DEPT GEOL & GEOPHYS,EDINBURGH EH9 3JW,SCOTLAND.
   UNIV COPENHAGEN,NIELS BOHR INST,DEPT GEOPHYS,DK-2200 COPENHAGEN,DENMARK.
   UNIV ICELAND,DEPT GEOPHYS,IS-107 REYKJAVIK,ICELAND.
   CTR ETUD SACLAY,CEA,DSM,MODELISAT CLIMAT & ENVIRONNEMENT LAB,F-91191 GIF SUR YVETTE,FRANCE.
   LAB GLACIOL & GEOPHYS ENVIRONM,F-38402 ST MARTIN DHERES,FRANCE.
C3 University of Edinburgh; University of Copenhagen; Niels Bohr Institute; University of Iceland; CEA; Universite Paris Saclay
RP THOUVENY, N (corresponding author), CNRS,GEOL QUATERNAIRE LAB,CASE 907,F-13288 MARSEILLE 09,FRANCE.
NR 34
TC 279
Z9 317
U1 0
U2 60
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 503
EP 506
DI 10.1038/371503a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900051
DA 2026-03-10
ER

PT J
AU ADAMS, MD
   KERLAVAGE, AR
   KELLEY, JM
   GOCAYNE, JD
   FIELDS, C
   FRASER, CM
   VENTER, JC
AF ADAMS, MD
   KERLAVAGE, AR
   KELLEY, JM
   GOCAYNE, JD
   FIELDS, C
   FRASER, CM
   VENTER, JC
TI A MODEL FOR HIGH-THROUGHPUT AUTOMATED DNA-SEQUENCING AND ANALYSIS CORE FACILITIES
SO NATURE
LA English
DT Article
ID genes; tags
RP ADAMS, MD (corresponding author), INST GENOM RES,932 CLOPPER RD,GAITHERSBURG,MD 20878, USA.
NR 19
TC 30
Z9 32
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 474
EP 475
DI 10.1038/368474a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000070
PM 8133896
DA 2026-03-10
ER

PT J
AU SAUNDERS, M
   JIMENEZVAZQUEZ, HA
   CROSS, RJ
   MROCZKOWSKI, S
   FREEDBERG, DI
   ANET, FAL
AF SAUNDERS, M
   JIMENEZVAZQUEZ, HA
   CROSS, RJ
   MROCZKOWSKI, S
   FREEDBERG, DI
   ANET, FAL
TI PROBING THE INTERIOR OF FULLERENES BY HE-3 NMR-SPECTROSCOPY OF ENDOHEDRAL HE-3-AT-C60 AND HE-3-AT-C70
SO NATURE
LA English
DT Article
ID current magnetic-susceptibility; icosahedral c-60; aromatic molecule; c60; complexes; c70; buckminsterfullerene; cage
AB FULLERENES have internal cavities large enough to encapsulate atoms1,2. Recently, noble-gas atoms were introduced into about one in a million fullerene molecules3. It is now possible to achieve far greater yields of these noble-gas endohedral compounds4. BecaUSe He-3 has a spin of 1/2 and is an excellent NMR nucleus5,6, it can be used as a probe for the magnetic shielding environment inside the fullerene cavity. This environment should reflect possible ring currents and hence the aromaticity in fullerenes7-15, an issue that measurements of magnetic susceptibility16,17 have not completely resolved. Here we present He-3 NMR spectra of the endohedral compounds He-3@C60 and He-3@C70 (the @ symbol denotes a compound that is endohedral). We find that the He-3 nuclei encapsulated in C60 and C70 are shielded by 6 and 29 parts per million respectively, relative to free He-3. These shieldings are unexpectedly large, indicating significant diamagnetic ring currents in C60 and very large ones in C70. Our results also show that, because of its small size and inertness, helium can serve as a useful probe of magnetic molecular properties. In addition, our work represents the first He-3 NMR spectra of stable helium compounds.
C1 YALE UNIV,DEPT APPL PHYS,NEW HAVEN,CT 06520.
   UNIV CALIF LOS ANGELES,DEPT CHEM & BIOCHEM,LOS ANGELES,CA 90024.
C3 Yale University; University of California System; University of California Los Angeles
RP SAUNDERS, M (corresponding author), YALE UNIV,DEPT CHEM,NEW HAVEN,CT 06520, USA.
NR 30
TC 334
Z9 345
U1 0
U2 64
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 256
EP 258
DI 10.1038/367256a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400050
DA 2026-03-10
ER

PT J
AU MISAWA, K
   FUJITA, T
AF MISAWA, K
   FUJITA, T
TI A RELICT REFRACTORY INCLUSION IN A FERROMAGNESIAN CHONDRULE FROM THE ALLENDE METEORITE
SO NATURE
LA English
DT Article
ID carbonaceous chondrites; ca,al-rich inclusion; opaque assemblages; rich inclusions; co3 meteorite; elements; origin; solar
AB CARBONACEOUS chondrites such as the Allende meteorite are composed of abundant ferromagnesian chondrules and (Ca, Al)rich inclusions (CAIs) embedded in a fine-grained matrix. The chondrules were formed by melting of pre-existing solid precursor materials(1), whereas CAIs formed either by direct condensation from the nebular gas or by high-temperature processing of solids in the nebula(2). These two components usually appear as discrete objects in chondrites, and are believed(3) to have formed independently before agglomeration of the chondrite parent bodies. However, elemental analyses of some Al-rich chondrules(4-8) suggest that there was a refractory component--such as CAIs--in the chondrule precursor material. We report here the discovery of a ferromagnesian chondrule from the Allende meteorite that contains an intact CAI fragment. This finding confirms that some CAIs co-existed with the precursor material of ferromagnesian chondrules, and helps to constrain the timing of the formation events of these two components.
C1 NATL INST POLAR RES,DEPT ANTARCTIC METEORITES,TOKYO 173,JAPAN.
   KYOTO UNIV,FAC SCI,DEPT GEOL & MINERAL,SAKYO KU,KYOTO 60601,JAPAN.
C3 Research Organization of Information & Systems (ROIS); National Institute of Polar Research (NIPR) - Japan; Kyoto University
NR 28
TC 30
Z9 30
U1 1
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 723
EP 726
DI 10.1038/368723a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300052
DA 2026-03-10
ER

PT J
AU KEIGWIN, LD
   CURRY, WB
   LEHMAN, SJ
   JOHNSEN, S
AF KEIGWIN, LD
   CURRY, WB
   LEHMAN, SJ
   JOHNSEN, S
TI THE ROLE OF THE DEEP-OCEAN IN NORTH-ATLANTIC CLIMATE-CHANGE BETWEEN 70-KYR AND 130-KYR AGO
SO NATURE
LA English
DT Article
ID continuous pollen record; circulation patterns; water circulation; greenland ice; cycle
AB THE suggestion(1) that changes in North Atlantic Deep Water (NADW) production are linked through surface heat flux to the atmospheric temperature over Greenland is supported by earlier indications(2,3) that NADW production decreased during glacial times, and by the subsequent finding(4-6) that it declined during the Younger Dryas cool period at the end of the last glaciation. Changes in North Atlantic surface temperatures have been found? to mirror high-frequency temperature changes recorded in Greenland ice cores over the past 80 kyr, but the connection to abyssal circulation has yet to be established, except for one or two isolated oscillations(8,9). Here we present carbon and oxygen isotope analyses of benthic foraminifera in a high-resolution North Atlantic deepsea sediment core for the period 70-130 kyr ago. These data allow us to reconstruct the history of NADW production, which shows a close correlation with Greenland climate variability for much of this time interval, suggesting that the climate influence of NADW variability was widespread. We see no evidence, however, for changes in NADW production during substage 5e (the Eemian interglacial period), in contrast with recent ice-core data(10) which suggest severe climate instability in Greenland during this time period. Our results may support suggestions, based on data from a second ice core, that this apparent instability is am artefact caused by ice flow(11). Alternatively, the Eemian climate instability may have had a different origin from the subsequent climate events.
C1 UNIV COPENHAGEN,NIELS BOHR INST,DEPT GEOPHYS,DK-1168 COPENHAGEN,DENMARK.
   UNIV ICELAND,INST SCI,DEPT GEOPHYS,IS-107 REYKJAVIK,ICELAND.
C3 University of Copenhagen; Niels Bohr Institute; University of Iceland
RP KEIGWIN, LD (corresponding author), WOODS HOLE OCEANOG INST,WOODS HOLE,MA 02543, USA.
NR 32
TC 173
Z9 183
U1 0
U2 21
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 323
EP 326
DI 10.1038/371323a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400049
DA 2026-03-10
ER

PT J
AU DAVIES, K
AF DAVIES, K
TI COSTS OF CONSANGUINITY
SO NATURE
LA English
DT Article
AB Analysis of the literature of the effects of consanguinity on mortality puts a figure on the price of inbreeding.
NR 8
TC 0
Z9 0
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 630
EP 630
DI 10.1038/371630a0
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900059
DA 2026-03-10
ER

PT J
AU MAEDA, T
   WURGLERMURPHY, SM
   SAITO, H
AF MAEDA, T
   WURGLERMURPHY, SM
   SAITO, H
TI A 2-COMPONENT SYSTEM THAT REGULATES AN OSMOSENSING MAP KINASE CASCADE IN YEAST
SO NATURE
LA English
DT Article
ID saccharomyces-cerevisiae; signal-transduction; escherichia-coli; shuttle vectors; protein; gene; chemotaxis; homology; strains
AB IN the prokaryotic two-component signal transduction systems, recognition of an environmental stimulus by a sensor molecule results in the activation of its histidine kinase domain and phosphorylation of a histidine residue within that domain(1-3). This phosphate group is then transferred to an aspartate residue in the receiver domain of a cognate response regulator molecule, resulting in the activation of its output function. Although a few eukaryotic proteins were identified recently that show sequence similarity to the prokaryotic sensors or response regulators, it has not been clear whether they constituted a part of a 'two-component' system(4-7). Here we describe a two-component system in Saccharomyces cerevisiae that regulates an osmosensing MAP kinase cascade(8,9).
C1 HARVARD UNIV,SCH MED,DANA FARBER CANC INST,DIV TUMOR IMMUNOL,BOSTON,MA 02115.
   HARVARD UNIV,SCH MED,DEPT BIOL CHEM & MOLEC PHARMACOL,BOSTON,MA 02115.
C3 Harvard University; Harvard Medical School; Harvard University Medical Affiliates; Dana-Farber Cancer Institute; Harvard University; Harvard Medical School
NR 25
TC 956
Z9 1061
U1 0
U2 38
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 242
EP 245
DI 10.1038/369242a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700059
PM 8183345
DA 2026-03-10
ER

PT J
AU CONDIE, BG
   CAPECCHI, MR
AF CONDIE, BG
   CAPECCHI, MR
TI MICE WITH TARGETED DISRUPTIONS IN THE PARALOGOUS GENES HOXA-3 AND HORD-3 REVEAL SYNERGISTIC INTERACTIONS
SO NATURE
LA English
DT Article
ID homeobox gene; homeotic transformations; developmental defects; mutant mice; mouse; hox-1.6; hindbrain; expression; vertebrae; region
AB THE Hox genes encode transcription factors which mediate the formation of the mammalian body plan along the anteroposterior and appendicular axes(1-15). Paralogous Hox genes within the separate linkage groups are closely related with respect to DNA sequence and expression(16,17), suggesting that they could have at least partially redundant functions. We showed previously that mice homozygous for independent targeted disruptions in the paralogous genes hoxa-3 and hoxd-3 had no defects in common(1,8). But our current analysis of double mutants has revealed strong, dosage-dependent interactions between these genes. We report here that in hoxd-3(-) homozygotes the first cervical vertebra, the atlas, is homeotically transformed to the adjacent anterior structure. Unexpectedly, in double mutants, rather than observing a more extensive homeotic transformation, the entire atlas is deleted. These observations are interpreted in terms of a model in which these Hox genes differentially regulate the proliferation rates of the appropriate sets of precursor cells.
C1 UNIV UTAH, SCH MED, HOWARD HUGHES MED INST, DEPT HUMAN GENET, SALT LAKE CITY, UT 84112 USA.
C3 Utah System of Higher Education; University of Utah; Howard Hughes Medical Institute
NR 22
TC 233
Z9 253
U1 0
U2 7
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 304
EP 307
DI 10.1038/370304a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900067
PM 7913519
DA 2026-03-10
ER

PT J
AU FICHEFET, T
   HOVINE, S
   DUPLESSY, JC
AF FICHEFET, T
   HOVINE, S
   DUPLESSY, JC
TI A MODEL STUDY OF THE ATLANTIC THERMOHALINE CIRCULATION DURING THE LAST GLACIAL MAXIMUM
SO NATURE
LA English
DT Article
ID north-atlantic; ocean circulation; surface; temperature; water
AB STABLE isotope measurements in deep-sea sediment cores have indicated that the Atlantic thermohaline circulation experienced significant changes during the last glacial maximum: the North Atlantic Deep Water (NADW) was shallower than today and the Antarctic Bottom Water (AABW) penetrated much farther north(1-6). Numerical ocean models have, so far, been unable to simulate these circulation changes realistically(7). Here we show that a zonally averaged, three-basin ocean model, driven by glacial boundary conditions(8-10), reproduces the main trends of the geochemically constrained glacial Atlantic circulation. In addition, we provide quantitative estimates of the meridional water transport during glacial times. Our results suggest that the glacial production of AABW was slightly higher than at present, whereas that of NADW was reduced by similar to 40%, resulting in an intermediate circulation cell which closed within the Atlantic basin. We also show that the strength of the Atlantic conveyor belt strongly depends on the surface density contrast between the high latitudes of the Northern and Southern hemispheres.
C1 CEA,CNRS LAB,CTR FAIBLES RADIOACT,F-91198 GIF SUR YVETTE,FRANCE.
C3 Universite Paris Saclay; CEA; Centre National de la Recherche Scientifique (CNRS)
RP FICHEFET, T (corresponding author), UNIV CATHOLIQUE LOUVAIN,INST ASTRON & GEOPHYS G LEMAITRE,B-1348 LOUVAIN,BELGIUM.
NR 24
TC 63
Z9 65
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 252
EP 255
DI 10.1038/372252a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900046
DA 2026-03-10
ER

PT J
AU ABDELILAH, S
   SOLNICAKREZEL, L
   STAINIER, DYR
   DRIEVER, W
AF ABDELILAH, S
   SOLNICAKREZEL, L
   STAINIER, DYR
   DRIEVER, W
TI IMPLICATIONS FOR DORSOVENTRAL AXIS DETERMINATION FROM THE ZEBRAFISH MUTATION JANUS
SO NATURE
LA English
DT Article
ID occurring diblastodermic eggs; xenopus-laevis; cell lineage; fate map; cleavage; embryos; expression; organizer; pattern; genes
AB THE mechanisms underlying the formation of dorsoventral polarity in the zebrafish Danio rerio are unknown. Here we describe the zebrafish recessive maternal-effect mutation janus(m55). The mutant phenotype is a division of the blastoderm along the first cleavage plane into two detached half-sized blastoderms. Partial-axis bifurcation occurs in a subset of mutants. Analysis of goosecoid expression in the mutant embryos indicates that only one organizer region is present in each embryo. Furthermore, the position of this organizer region is random with respect to the first cleavage plant bisecting the two blastoderms. Finally, cell tracing in wild-type embryos demonstrates that there is no strict correlation of the dorsoventral axis with early cleavage planes in zebrafish. These findings support the notion that the establishment of the dorsoventral axis and the first cleavage planes are determined by separate mechanisms in the zebrafish embryo.
C1 HARVARD UNIV,SCH MED,BOSTON,MA 02129.
C3 Harvard University; Harvard Medical School
RP ABDELILAH, S (corresponding author), MASSACHUSETTS GEN HOSP,CARDIOVASC RES CTR,13TH ST,BLDG 149,BOSTON,MA 02129, USA.
NR 24
TC 46
Z9 54
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 468
EP 471
DI 10.1038/370468a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700058
PM 8047167
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI AGAINST-THE-GRAIN
SO NATURE
LA English
DT Article
NR 1
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 799
EP 799
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700033
DA 2026-03-10
ER

PT J
AU AASLAND, S
   MCMILLAN, PF
AF AASLAND, S
   MCMILLAN, PF
TI DENSITY-DRIVEN LIQUID-LIQUID PHASE-SEPARATION IN THE SYSTEM AL2O3-Y2O3
SO NATURE
LA English
DT Article
ID induced coordination changes; high-pressure; raman-spectroscopy; metal transition; yttrium aluminum; water; melt; glasses; garnets; carbon
AB Phase separation of liquid mixtures into two liquids with different compositions is a well-known phenomenon. It has been proposed(1-9) that another type of liquid-liquid phase separation, driven by fluctuations in density rather than in composition, may occur in some elemental systems. Transitions between low- and high-density amorphous phases have been described for the one-component oxides H2O, SiO2 and GeO2 (refs 10-17), and it has been suggested(18-21) that a liquid-liquid phase transition might occur in supercooled water. If density-driven phase separation truly does occur in liquid mixtures, it should be possible to observe the coexistence of two liquids with the same composition but different density. Here we report the direct observation of such a situation. We observe two coexisting liquid phases in the supercooled melt of Al2O3-Y2O3 just above the glass transition at ambient pressure, both of which have the same composition. We propose that these two phases must differ solely in density, and that the transition is entropically driven. The occurrence of the phase transition in this system may explain why the crystallization of yttrium aluminium garnet, the host material for Nd3+ ions in YAG lasers, is sluggish(22-25).
C1 ARIZONA STATE UNIV,DEPT CHEM & BIOCHEM,TEMPE,AZ 85287.
C3 Arizona State University; Arizona State University-Tempe
NR 43
TC 390
Z9 422
U1 2
U2 147
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 633
EP 636
DI 10.1038/369633a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900050
DA 2026-03-10
ER

PT J
AU SCHNELL, L
   SCHNEIDER, R
   KOLBECK, R
   BARDE, YA
   SCHWAB, ME
AF SCHNELL, L
   SCHNEIDER, R
   KOLBECK, R
   BARDE, YA
   SCHWAB, ME
TI NEUROTROPHIN-3 ENHANCES SPROUTING OF CORTICOSPINAL TRACT DURING DEVELOPMENT AND AFTER ADULT SPINAL-CORD LESION
SO NATURE
LA English
DT Article
ID neurite growth-inhibitors; nervous-system; messenger-rna; rat; axons; brain; motoneurons; expression; extension; survival
AB THE number of neurotrophic factors found in the central nervous system is rapidly growing, but their functions in vivo are largely unknown. In the peripheral nervous system they promote the survival of developing and lesioned neurons and enhance nerve fibre growth and regeneration1-6. Here we study the effects of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) on the largest tract system leading from the brain to the spinal cord, the corticospinal tract (CST)7. The developing CST grows down the spinal cord during the first postnatal days and innervates its targets after a waiting period by collateral sprouting8-10. We find that NT-3 injected locally specifically enhances this sprouting, whereas BDNF has no effect. In adult rats, injection of NT-3 (but not BDNF) into the lesioned spinal cord increases the regenerative sprouting of the transected CST. The distance of growth of the sprouts is very restricted, but application of an antibody that neutralizes myelin-associated neurite growth inhibitory proteins'' results in long-distance regeneration of CST fibres.
C1 MAX PLANCK INST PSYCHIAT,DEPT NEUROBIOCHEM,D-82152 MARTINSRIED,GERMANY.
C3 Max Planck Society
RP SCHNELL, L (corresponding author), UNIV ZURICH,BRAIN RES INST,AUGUST FOREL STR 1,CH-8029 ZURICH,SWITZERLAND.
NR 28
TC 792
Z9 891
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 170
EP 173
DI 10.1038/367170a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000060
PM 8114912
DA 2026-03-10
ER

PT J
AU WILSON, R
   AINSCOUGH, R
   ANDERSON, K
   BAYNES, C
   BERKS, M
   BURTON, J
   CONNELL, M
   BONFIELD, J
   COPSEY, T
   COOPER, J
   COULSON, A
   CRAXTON, M
   DEAR, S
   DU, Z
   DURBIN, R
   FAVELLO, A
   FRASER, A
   FULTON, L
   GARDNER, A
   GREEN, P
   HAWKINS, T
   HILLIER, L
   JIER, M
   JOHNSTON, L
   JONES, M
   KERSHAW, J
   KIRSTEN, J
   LAISSTER, N
   LATREILLE, P
   LLOYD, C
   MORTIMORE, B
   OCALLAGHAN, M
   PARSONS, J
   PERCY, C
   RIFKEN, L
   ROOPRA, A
   SAUNDERS, D
   SHOWNKEEN, R
   SIMS, M
   SMALDON, N
   SMITH, A
   SMITH, M
   SONNHAMMER, E
   STADEN, R
   SULSTON, J
   THIERRYMIEG, J
   THOMAS, K
   VAUDIN, M
   VAUGHAN, K
   WATERSTON, R
   WATSON, A
   WEINSTOCK, L
   WILKINSONSPROAT, J
   WOHLDMAN, P
AF WILSON, R
   AINSCOUGH, R
   ANDERSON, K
   BAYNES, C
   BERKS, M
   BURTON, J
   CONNELL, M
   BONFIELD, J
   COPSEY, T
   COOPER, J
   COULSON, A
   CRAXTON, M
   DEAR, S
   DU, Z
   DURBIN, R
   FAVELLO, A
   FRASER, A
   FULTON, L
   GARDNER, A
   GREEN, P
   HAWKINS, T
   HILLIER, L
   JIER, M
   JOHNSTON, L
   JONES, M
   KERSHAW, J
   KIRSTEN, J
   LAISSTER, N
   LATREILLE, P
   LLOYD, C
   MORTIMORE, B
   OCALLAGHAN, M
   PARSONS, J
   PERCY, C
   RIFKEN, L
   ROOPRA, A
   SAUNDERS, D
   SHOWNKEEN, R
   SIMS, M
   SMALDON, N
   SMITH, A
   SMITH, M
   SONNHAMMER, E
   STADEN, R
   SULSTON, J
   THIERRYMIEG, J
   THOMAS, K
   VAUDIN, M
   VAUGHAN, K
   WATERSTON, R
   WATSON, A
   WEINSTOCK, L
   WILKINSONSPROAT, J
   WOHLDMAN, P
TI 2.2 MB OF CONTIGUOUS NUCLEOTIDE-SEQUENCE FROM CHROMOSOME-III OF C-ELEGANS
SO NATURE
LA English
DT Article
ID nematode caenorhabditis-elegans; editing program; dna; genome; genes; encodes; similarity; protein; lin-12; rna
AB As part of our effort to sequence the 100-megabase (Mb) genome of the nematode Caenorhabditis elegans, we have completed the nucleotide sequence of a contiguous 2,181,032 base pairs in the central gene cluster of chromosome III. Analysis of the finished sequence has indicated an average density of about one gene per five kilobases; comparison with the public sequence databases reveals similarities to previously known genes for about one gene in three. In addition, the genomic sequence contains several intriguing features, including putative gene duplications and a variety of other repeats with potential evolutionary implications.
C1 WASHINGTON UNIV,SCH MED,CTR GENOME SEQUENCING,ST LOUIS,MO 63110.
   MRC,MOLEC BIOL LAB,CAMBRIDGE CB10 1RQ,CAMBS,ENGLAND.
   SANGER CTR,CAMBRIDGE CB10 1RQ,CAMBS,ENGLAND.
   CNRS,CTR RECH BIOCHIM MACROMOLEC & PHYS MATH,F-34033 MONTPELLIER,FRANCE.
C3 Washington University (WUSTL); MRC Laboratory Molecular Biology; Wellcome Trust Sanger Institute; Centre National de la Recherche Scientifique (CNRS)
RP WILSON, R (corresponding author), WASHINGTON UNIV,SCH MED,DEPT GENET,ST LOUIS,MO 63110, USA.
NR 49
TC 1281
Z9 1438
U1 1
U2 29
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 32
EP 38
DI 10.1038/368032a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900044
PM 7906398
DA 2026-03-10
ER

PT J
AU TOKIWA, G
   TYERS, M
   VOLPE, T
   FUTCHER, B
AF TOKIWA, G
   TYERS, M
   VOLPE, T
   FUTCHER, B
TI INHIBITION OF G1 CYCLIN ACTIVITY BY THE RAS/CAMP PATHWAY IN YEAST
SO NATURE
LA English
DT Article
ID dependent protein-kinase; saccharomyces-cerevisiae; cell-size; positive feedback; gene-expression; budding yeast; s-cerevisiae; camp; transcription; division
AB IN the yeast Saccharomyces cerevisiae, commitment to cell division (Start) requires growth to a critical cell size(1-3). The G1 cyclins Cln1, Cln2 and Cln3 activate the Cdc28 protein kinase and are rate-limiting activators of Start(4-6). When glucose is added to cells growing in a poor carbon source, the critical cell size required for Start is reset from a small to a large size(2,3,7). In yeast, glucose acts through Ras proteins to stimulate adenylyl cyclase, activating the three cyclic AMP-dependent protein kinases Tpk1, Tpk2 and Tpk3 (refs 8, 9). We find that stimulation of the Ras/cAMP pathway represses expression of CLN1, CLN2 and co-regulated genes, inhibiting Start. This helps explain the increase in critical size when cells are shifted from poor to rich medium. This connection between the molecules controlling growth (Ras/cAMP) and those controlling division (cyclins) helps explain how division is co-ordinated with growth.
C1 COLD SPRING HARBOR LAB,COLD SPRING HARBOR,NY 11724.
   SUNY STONY BROOK,GRAD PROGRAM GENET,STONY BROOK,NY 11792.
   UNIV TORONTO,BANTING & BEST DEPT MED RES,TORONTO M5G 1L6,ON,CANADA.
C3 Cold Spring Harbor Laboratory; State University of New York (SUNY) System; Stony Brook University; University of Toronto
NR 30
TC 172
Z9 193
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 342
EP 345
DI 10.1038/371342a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400055
PM 8090204
DA 2026-03-10
ER

PT J
AU ODONOVAN, A
   DAVIES, AA
   MOGGS, JG
   WEST, SC
   WOOD, RD
AF ODONOVAN, A
   DAVIES, AA
   MOGGS, JG
   WEST, SC
   WOOD, RD
TI XPG ENDONUCLEASE MAKES THE 3' INCISION IN HUMAN DNA NUCLEOTIDE EXCISION-REPAIR
SO NATURE
LA English
DT Article
ID complementation group-g; pigmentosum group-f; xeroderma-pigmentosum; saccharomyces-cerevisiae; schizosaccharomyces-pombe; rad2; proteins; defects; ercc1; gene
AB HUMANS With a defect in the XPG protein suffer from xeroderma pigmentosum (XP) resulting from an inability to perform DNA nucleotide excision repair properly(1-4). Here we show that XPG makes a structure-specific endonucleolytic incision in a synthetic DNA substrate containing a duplex region and single-stranded arms. One strand of the duplex is cleaved at the border with single-stranded DNA. A cut with the same polarity is also made in a bubble structure, at the 3' side of the centrally unpaired region. Normal cell extracts introduce a nick 3' to a platinum-DNA lesion, but an XP-G cell extract is defective in making this incision. These data show that XPG has a direct role in making one of the incisions required to excise a damaged oligonucleotide, by cleaving 3' to DNA damage during nucleotide excision repair.
RP ODONOVAN, A (corresponding author), IMPERIAL CANC RES FUND,CLARE HALL LABS,S MIMMS EN6 3LD,HERTS,ENGLAND.
NR 27
TC 411
Z9 476
U1 1
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 432
EP 435
DI 10.1038/371432a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500047
PM 8090225
DA 2026-03-10
ER

PT J
AU LIU, F
   GREEN, MR
AF LIU, F
   GREEN, MR
TI PROMOTER TARGETING BY ADENOVIRUS-E1A THROUGH INTERACTION WITH DIFFERENT CELLULAR DNA-BINDING DOMAINS
SO NATURE
LA English
DT Article
ID eukaryotic transcriptional activators; retinoblastoma gene-product; e1a proteins; mammalian-cells; factor family; transactivation; element; identification; transformation; expression
AB A puzzling property of the transcriptional activators encoded by several animal viruses is their ability to function promiscuously. The adenovirus E1a protein, for example, stimulates transcription of adenoviral genes as well as a wide variety of other viral and cellular genes. We show that E1a can interact with several classes of cellular DNA-binding domains and thereby be recruited to diverse promoters. Our results explain how a single protein can regulate transcription of multiple genes that lack a common promoter element.
C1 UNIV MASSACHUSETTS, MED CTR, PROGRAM MOLEC MED, WORCESTER, MA 01605 USA.
C3 University of Massachusetts System; University of Massachusetts Worcester
RP LIU, F (corresponding author), HARVARD UNIV, DEPT BIOCHEM & MOLEC BIOL, 7 DIVIN AVE, CAMBRIDGE, MA 02138 USA.
NR 44
TC 245
Z9 271
U1 0
U2 2
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 520
EP 525
DI 10.1038/368520a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500045
PM 8139685
DA 2026-03-10
ER

PT J
AU STEHLE, T
   YAN, YW
   BENJAMIN, TL
   HARRISON, SC
AF STEHLE, T
   YAN, YW
   BENJAMIN, TL
   HARRISON, SC
TI STRUCTURE OF MURINE POLYOMAVIRUS COMPLEXED WITH AN OLIGOSACCHARIDE RECEPTOR FRAGMENT
SO NATURE
LA English
DT Article
ID influenza-virus hemagglutinin; sialyloligosaccharide receptors; sialic-acid; resolution; binding; vp1
AB THE polyomaviruses are non-enveloped, icosahedrally symmetrical particles with circular double-stranded DNA genomes(1,2). The outer shell of the virion contains 360 copies of viral protein VP1 (M(r) similar to 42K) arranged in pentamers(3). We report here the structure at 3.65 Angstrom resolution of murine polyomavirus ('polyoma') complexed with an oligosaccharide receptor fragment. This structure has been determined using the previously described model of simian virus 40 (SV40)(4). Although very similar in structure to SV40, polyoma has interesting biological differences. Cell-surface N-acetyl neuraminic acid (sialic acid) is required for polyoma infectivity, but not for SV40. Polyoma attaches to the surface of susceptible cells by stereospecific recognition of oligosaccharides terminating in (alpha 2,3)-linked sialic acid(5,6). Studies of pathogenicity show that the specificity of viral binding to such oligosaccharides is an important determinant of the virus' ability to establish a disseminated infection and to induce tumours in the natural host. The complex described here shows how polyoma recognizes the receptor fragment and how strains with different receptor specificities can distinguish between alternative ligands. The results also suggest an explanation for the large disparity in pathogenicity exhibited by strains differing in only one amino-acid residue of Vp1(7,8).
C1 HARVARD UNIV,HOWARD HUGHES MED INST,CAMBRIDGE,MA 02138.
   HARVARD UNIV,SCH MED,DEPT PATHOL,BOSTON,MA 02115.
C3 Howard Hughes Medical Institute; Harvard University; Harvard University; Harvard Medical School
RP STEHLE, T (corresponding author), HARVARD UNIV,DEPT BIOCHEM & MOLEC BIOL,CAMBRIDGE,MA 02138, USA.
NR 22
TC 269
Z9 316
U1 0
U2 22
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 160
EP 163
DI 10.1038/369160a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100053
PM 8177322
DA 2026-03-10
ER

PT J
AU NORTHROP, JP
   HO, SN
   CHEN, L
   THOMAS, DJ
   TIMMERMAN, LA
   NOLAN, GP
   ADMON, A
   CRABTREE, GR
AF NORTHROP, JP
   HO, SN
   CHEN, L
   THOMAS, DJ
   TIMMERMAN, LA
   NOLAN, GP
   ADMON, A
   CRABTREE, GR
TI NF-AT COMPONENTS DEFINE A FAMILY OF TRANSCRIPTION FACTORS TARGETED IN T-CELL ACTIVATION
SO NATURE
LA English
DT Article
ID nuclear factor; antigen receptor; mammalian-cells; lymphocyte; identification; calcineurin; complex; invitro; events; assay
AB THE NF-AT transcription complex(1) is required far the expression of a group of proteins that collectively coordinate the immune response(2-4). Here we purify two proteins encoded by separate genes that represent the pre-existing (p) and cytosolic (c) components of NF-AT. Expression of the full-length complementary DNA encoding NF-AT(c) activates the interleukin (IL-2) promoter in non-T lymphocytes, whereas a dominant negative of NF-AT(c), specifically blocks activation of the IL-2 promoter in T lymphocytes, indicating that NF-AT(c) is required for IL-2 gene expression. NF-AT(c) RNA expression is largely restricted to lymphoid tissues and is induced upon T-cell activation. The other protein, NF-AT(p), is highly homologous to NF-AT(c) over a limited domain which shows similarity to the Dorsal/Rel family(5), but has a wider tissue distribution. Agents that increase intracellular Ca2+ or activate protein kinase C independently modify NF-AT(c), indicating that distinct signalling pathways converge on NF-AT(c) to regulate its function.
C1 STANFORD UNIV,SCH MED,DEPT PATHOL,STANFORD,CA 94305.
   STANFORD UNIV,SCH MED,DEPT MOLEC PHARMACOL,STANFORD,CA 94305.
   UNIV CALIF BERKELEY,DEPT MOLEC & CELL BIOL,BERKELEY,CA 94720.
C3 Stanford University; Stanford University; University of California System; University of California Berkeley
RP NORTHROP, JP (corresponding author), STANFORD UNIV,SCH MED,HOWARD HUGHES MED INST,DEPT DEV BIOL,STANFORD,CA 94305, USA.
NR 20
TC 561
Z9 613
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 497
EP 502
DI 10.1038/369497a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600061
PM 8202141
DA 2026-03-10
ER

PT J
AU FARKAS, G
   GAUSZ, J
   GALLONI, M
   REUTER, G
   GYURKOVICS, H
   KARCH, F
AF FARKAS, G
   GAUSZ, J
   GALLONI, M
   REUTER, G
   GYURKOVICS, H
   KARCH, F
TI THE TRITHORAX-LIKE GENE ENCODES THE DROSOPHILA GAGA FACTOR
SO NATURE
LA English
DT Article
ID position-effect variegation; bithorax complex; transcription; melanogaster; chromatin; proteins; antirepression; segmentation; transposon; expression
AB LITTLE is known about the way higher-order chromatin structure influences gene expression and chromosome topology in general. Genetic analysis in Drosophila has led to the discovery of two classes of genes, the regulators of homeotic genes and the modifiers of position-effect variegation, which seem to be good candidates for encoding some of the factors regulating chromatin functions(1,2). The Trithorax-like gene we describe here is required for the normal expression of the homeotic genes and is a modifier of position-effect variegation. We found that Trithorax-like encodes the GAGA factor which is involved in the formation of an accessible chromatin structure at promoter sequences(3). Our genetic analysis suggests that the chromatin modelling function of the GAGA factor is not restricted to promoter regions.
C1 HUNGARIAN ACAD SCI,BIOL RES CTR,INST GENET,H-6701 SZEGED,HUNGARY.
   UNIV GENEVA,DEPT ZOOL & ANIM BIOL,CH-1224 GENEVA,SWITZERLAND.
   UNIV HALLE WITTENBERG,INST GENET,D-06108 HALLE,GERMANY.
C3 Hungarian Academy of Sciences; HUN-REN; HUN-REN Biological Research Center; Institute of Genetics - HAS; University of Geneva; Martin Luther University Halle Wittenberg
NR 27
TC 362
Z9 389
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 806
EP 808
DI 10.1038/371806a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800062
PM 7935842
DA 2026-03-10
ER

PT J
AU ANDERSON, BL
AF ANDERSON, BL
TI THE ROLE OF PARTIAL OCCLUSION IN STEREOPSIS
SO NATURE
LA English
DT Article
ID perception; depth
AB MODELS of stereopsis typically assume that all the information about stereoscopic depth is contained in the disparity field, that is, the positional differences of image features that arise from surfaces visible to both eyes. But such models have difficulty in resolving image regions containing occlusions, because a portion of the occluded surface is visible to only one of the two eyes ('half-occlusions')1. Here I present displays revealing an unexpected relationship between interocular differences in image position and occluding contours. The partial occlusion of contours can give rise to both horizontal and vertical image differences that are not disparities. The results show that the visual system interprets these image differences as signalling the presence of occluding contours. Even when a single line segment serves as a binocular target, subjective contours form that can appear both oriented and in depth. These local subjective contours have a strong tendency to interact cooperatively and form global contours not present in the monocular images. These and other findings2-4 show that stereoscopic processing actively decomposes vertical and horizontal image differences into disparities and half-occlusions. The two sources of information are complementary: while disparity provides relative depth information about surface features visible to both eyes, half-occlusions provide information to segment the visual world into coherent objects at object boundaries.
RP ANDERSON, BL (corresponding author), RUTGERS UNIV,VIS RES LAB,PISCATAWAY,NJ 08854, USA.
NR 13
TC 87
Z9 92
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 365
EP 368
DI 10.1038/367365a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000066
PM 8114935
DA 2026-03-10
ER

PT J
AU SATO, H
   TAKINO, T
   OKADA, Y
   CAO, J
   SHINAGAWA, A
   YAMAMOTO, E
   SEIKI, M
AF SATO, H
   TAKINO, T
   OKADA, Y
   CAO, J
   SHINAGAWA, A
   YAMAMOTO, E
   SEIKI, M
TI A MATRIX METALLOPROTEINASE EXPRESSED ON THE SURFACE OF INVASIVE TUMOR-CELLS
SO NATURE
LA English
DT Article
ID iv collagenase; interstitial collagenase; tissue inhibitor; activation; fibroblasts; gelatinase; association; metastasis; carcinoma; precursor
AB GELATINASE A (type-IV collagenase; M(r) 72,000) is produced by tumour stroma cells and is believed to be crucial for their invasion and metastasis, acting by degrading extracellular matrix macromolecules such as type IV collagen(1-3). An inactive precursor of gelatinase A (pro-gelatinase A) is secreted and activated in invasive tumour tissue(4-7) as a result of proteolysis which is mediated by a fraction of tumour cell membrane that is sensitive to metalloproteinase inhibitors(4,5). Here we report the cloning of the complementary DNA encoding a new matrix metalloproteinase with a potential transmembrane domain. Expression of the gene product on the cell surface induces specific activation of pro-gelatinase A in vitro and enhances cellular invasion of the reconstituted basement membrane. Tumour cells of invasive lung carcinomas, which contain activated forms of gelatinase A, were found to express the transcript and the gene product. The new metalloproteinase may thus trigger invasion by tumour cells by activating pro-gelatinase A on the tumour cell surface.
C1 KANAZAWA UNIV,CANC RES INST,DEPT MOLEC VIROL & ONCOL,KANAZAWA,ISHIKAWA 920,JAPAN.
   KANAZAWA UNIV,SCH MED,DEPT ORAL SURG,KANAZAWA,ISHIKAWA 920,JAPAN.
   KANAZAWA UNIV,SCH MED,DEPT PATHOL,KANAZAWA,ISHIKAWA 920,JAPAN.
   FUJI CHEM IND CO LTD,RES INST,DEPT BIOCHEM,TAKAOKA,TOYAMA 933,JAPAN.
C3 Kanazawa University; Kanazawa University; Kanazawa University
NR 30
TC 2407
Z9 2621
U1 1
U2 110
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 61
EP 65
DI 10.1038/370061a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100059
PM 8015608
DA 2026-03-10
ER

PT J
AU FLING, SP
   ARP, B
   PIOUS, D
AF FLING, SP
   ARP, B
   PIOUS, D
TI HLA-DMA AND HLA-DMB GENES ARE BOTH REQUIRED FOR MHC CLASS-II PEPTIDE COMPLEX-FORMATION IN ANTIGEN-PRESENTING CELLS
SO NATURE
LA English
DT Article
ID major histocompatibility complex; invariant chain peptides; monoclonal-antibody; processing mutant; dr molecules; expression; populations; region; vector; line
AB MAJOR histocompatibility complex (MHC) class II molecules are highly polymorphic cell-surface glycoproteins that present antigenic peptides to CD4+ T lymphocytes. The normal assembly of class II molecules with cognate peptides for antigen presentation requires an accessory function provided by a gene mapping to the class II region of the HLA complex1,2.  The isolation of somatic cell mutants of antigen-presenting cells (APC) has shown that at least one gene which maps between HLA-DP and HLA-DQ, provisionally designated c2p-1 (ref. 3), mediates this process1,2,4. Here we describe a unique new mutant 2.2.93, which manifests defective formation of class II/peptide complexes like that described in c2p-1 mutants. We show that (1) mutant 2.2.93 contains a mutation in HLA-DMA5, and a representative c2p-1 mutant, 9.5.3, contains a mutation in HLA-DMB5; and (2) transfection and expression of DMA complementary DNA in 2.2.93, and DMB cDNA in 9.5.3, reverses their mutant phenotypes. These results show that HLA-DMA and -DMB, genes of previously unknown function mapping between HLA-DP and HLA-DQ5, are required for the normal assembly of peptides with MHC class II molecules. They suggest that HLA-DMA and -DMB encode subunits of a functional heterodimer which is critical in the pathway of class II antigen presentation.
C1 UNIV WASHINGTON,DEPT PEDIAT,SEATTLE,WA 98195.
   UNIV WASHINGTON,DEPT IMMUNOL,SEATTLE,WA 98195.
   UNIV WASHINGTON,DEPT GENET,SEATTLE,WA 98195.
C3 University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle
NR 30
TC 291
Z9 310
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 554
EP 558
DI 10.1038/368554a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500057
PM 8139690
DA 2026-03-10
ER

PT J
AU MANGO, FD
   HIGHTOWER, JW
   JAMES, AT
AF MANGO, FD
   HIGHTOWER, JW
   JAMES, AT
TI ROLE OF TRANSITION-METAL CATALYSIS IN THE FORMATION OF NATURAL-GAS
SO NATURE
LA English
DT Article
ID petroleum generation; oil; pyrolysis; kerogen; components; stability; shales; basin
AB THE idea that natural gas is formed by thermal decomposition of sedimentary organic matter1,2 enjoys almost universal acceptance3-6. But pyrolysis experiments on organic matter7-13 have failed to reproduce the composition of natural gas (typically 90% methane). It has recently been suggested14 that natural gas may instead be generated catalytically: transition metals are often found in carbonaceous sedimentary rocks, and might promote the reaction between hydrogen and n-alkenes (which are themselves formed during thermal decomposition of kerogen) to give light hydrocarbons and natural gas. We report here experimental results that support this hypothesis. In particular, we find that n-alkenes, hydrogen and a carbonaceous sedimentary rock containing moderately high concentrations of transition metals react under mild conditions (approximately 200-degrees-C) to generate a light-hydrocarbon product indistinguishable from natural gas in both molecular and carbon isotope composition. Our results demonstrate that the reaction is indeed catalytic, and could alter the way in which we view the generation and distribution of oil and gas in the Earth.
C1 RICE UNIV,DEPT CHEM ENGN,HOUSTON,TX 77251.
   EXXON PROD RES CO,HOUSTON,TX.
C3 Rice University; Exxon Mobil Corporation
RP MANGO, FD (corresponding author), RICE UNIV,DEPT GEOL & GEOPHYS,HOUSTON,TX 77251, USA.
NR 33
TC 150
Z9 193
U1 0
U2 42
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 536
EP 538
DI 10.1038/368536a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500051
DA 2026-03-10
ER

PT J
AU BRONNER, CE
   BAKER, SM
   MORRISON, PT
   WARREN, G
   SMITH, LG
   LESCOE, MK
   KANE, M
   EARABINO, C
   LIPFORD, J
   LINDBLOM, A
   TANNERGARD, P
   BOLLAG, RJ
   GODWIN, AR
   WARD, DC
   NORDENSKJOLD, M
   FISHEL, R
   KOLODNER, R
   LISKAY, RM
AF BRONNER, CE
   BAKER, SM
   MORRISON, PT
   WARREN, G
   SMITH, LG
   LESCOE, MK
   KANE, M
   EARABINO, C
   LIPFORD, J
   LINDBLOM, A
   TANNERGARD, P
   BOLLAG, RJ
   GODWIN, AR
   WARD, DC
   NORDENSKJOLD, M
   FISHEL, R
   KOLODNER, R
   LISKAY, RM
TI MUTATION IN THE DNA MISMATCH REPAIR GENE HOMOLOG HMLH1 IS ASSOCIATED WITH HEREDITARY NONPOLYPOSIS COLON-CANCER
SO NATURE
LA English
DT Article
ID saccharomyces-cerevisiae; nucleotide-sequence; streptococcus-pneumoniae; salmonella-typhimurium; insitu hybridization; pms1; mutl; hexb
AB THE human DNA mismatch repair gene homologue, hMSH2, on chromosome 2p is involved in hereditary non-polyposis colon cancer (HNPCC)(1,2). On the basis of linkage data, a second HNPCC locus was assigned to chromosome 3p21-23 (ref. 3). Here we report that a human gene encoding a protein, hMLH1 (human MutL homologue), homologous to the bacterial DNA mismatch repair protein MutL, is located on human chromosome 3p21.3-23. We propose that hMLH1 is the HNPCC gene located on 3p because of the similarity of the hMLH1 gene product to the yeast DNA mismatch repair protein, MLH1(4,5), the coincident location of the hMLH1 gene and the HNPCC locus on chromosome 3, and hMLH1 missense mutations in affected individuals from a chromosome 3-linked HNPCC family.
C1 OREGON HLTH SCI UNIV,DEPT MOLEC & MED GENET,PORTLAND,OR 97201.
   DANA FARBER CANC INST,MOLEC BIOL CORE FACIL,BOSTON,MA 02115.
   YALE UNIV,SCH MED,DEPT GENET,NEW HAVEN,CT 06510.
   YALE UNIV,SCH MED,DEPT MOLEC BIOPHYS & BIOCHEM,NEW HAVEN,CT 06510.
   UNIV VERMONT,MARKEY CTR MOLEC GENET,DEPT MICROBIOL & MOLEC GENET,BURLINGTON,VT 05405.
   HARVARD UNIV,SCH MED,DANA FARBER CANC INST,DIV CELLULAR & MOLEC BIOL,BOSTON,MA 02115.
   HARVARD UNIV,SCH MED,DEPT BIOL CHEM & MOLEC PHARMACOL,BOSTON,MA 02115.
   KAROLINSKA HOSP,DEPT MOLEC MED,S-17176 STOCKHOLM,SWEDEN.
C3 Oregon Health & Science University; Harvard University; Harvard University Medical Affiliates; Dana-Farber Cancer Institute; Yale University; Yale University; University of Vermont; Harvard University; Harvard Medical School; Harvard University Medical Affiliates; Dana-Farber Cancer Institute; Harvard University; Harvard Medical School; Karolinska Institutet; Karolinska University Hospital
NR 30
TC 1882
Z9 2067
U1 0
U2 113
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 258
EP 261
DI 10.1038/368258a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000060
PM 8145827
DA 2026-03-10
ER

PT J
AU HEINZE, HJ
   MANGUN, GR
   BURCHERT, W
   HINRICHS, H
   SCHOLZ, M
   MUNTE, TF
   GOS, A
   SCHERG, M
   JOHANNES, S
   HUNDESHAGEN, H
   GAZZANIGA, MS
   HILLYARD, SA
AF HEINZE, HJ
   MANGUN, GR
   BURCHERT, W
   HINRICHS, H
   SCHOLZ, M
   MUNTE, TF
   GOS, A
   SCHERG, M
   JOHANNES, S
   HUNDESHAGEN, H
   GAZZANIGA, MS
   HILLYARD, SA
TI COMBINED SPATIAL AND TEMPORAL IMAGING OF BRAIN ACTIVITY DURING VISUAL SELECTIVE ATTENTION IN HUMANS
SO NATURE
LA English
DT Article
ID pet images; cortex
AB VISUAL-SPATIAL attention is an essential brain function that enables os to select and preferentially process high priority information in the visual fields. Several brain areas have been shown to participate in the control of spatial attention in humans(3-5), but little is known about the underlying selection mechanisms. Non-invasive scalp recordings of event-related potentials (e.r.ps) in humans have shown that attended visual stimuli are preferentially selected as early as 80-90 ms after stimulus onset(6,7), but current e.r.p. methods do not permit a- precise localization of the participating cortical areas. In this study we combined neuroimaging (positron emission tomography) with e.r.p. recording in order to describe both the cortical anatomy and time course of attentional selection processes. Together these methods showed that visual inputs from attended locations receive enhanced processing in the extrastriate cortex (fusiform gyrus) at 80-130 ms after stimulus onset. These findings reinforce early selection models of attention(8-10).
C1 UNIV CALIF DAVIS, DEPT PSYCHOL, DAVIS, CA 95616 USA.
   UNIV CALIF DAVIS, CTR NEUROSCI, DAVIS, CA 95616 USA.
   HANNOVER MED SCH, DEPT NUCL MED, W-3000 HANNOVER, GERMANY.
   UNIV HEIDELBERG, DEPT NEUROL, HEIDELBERG, GERMANY.
   UNIV CALIF SAN DIEGO, DEPT NEUROSCI, LA JOLLA, CA 92093 USA.
C3 University of California System; University of California Davis; University of California System; University of California Davis; Hannover Medical School; Ruprecht Karls University Heidelberg; University of California System; University of California San Diego
RP HEINZE, HJ (corresponding author), UNIV MAGDEBURG, DEPT CLIN NEUROPHYSIOL, D-39120 MAGDEBURG, GERMANY.
NR 30
TC 785
Z9 855
U1 1
U2 57
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 543
EP 546
DI 10.1038/372543a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200050
PM 7990926
DA 2026-03-10
ER

PT J
AU GAFFNEY, ES
   KITCHING, JW
AF GAFFNEY, ES
   KITCHING, JW
TI THE MOST ANCIENT AFRICAN TURTLE
SO NATURE
LA English
DT Article
AB ALTHOUGH turtles obviously differ greatly from other tetrapods in their shell, the turtle skull is so highly modified that turtle origins are difficult to resolve without evidence about the order of character acquisition. We report here the discovery of a turtle in the Early Jurassic Elliot Formation, South Africa, which extends the history of turtles in Africa by 60 million years, and reveals a previously unknown stage in the early evolution of turtles. This new skull is dominated by primitive characters held in common with the most primitive turtle known, the Late Triassic Proganochelys but, more notably, it is advanced in some important features. Previous turtle phylogenies suggest that most of the typical chelonian skull features evolved after turtles split into the two major groups, the Cryptodira and the Pleurodira. But this skull demonstrates that important cranial reorganization unexpectedly took place before the origin of the modern turtle groups. The reasons for this are unclear, but it may be related to the early evolution of hearing adaptations.
C1 UNIV WITWATERSRAND,BERNARD PRICE INST PALAEONTOL RES,JOHANNESBURG 2001,SOUTH AFRICA.
C3 University of Witwatersrand
RP GAFFNEY, ES (corresponding author), AMER MUSEUM NAT HIST,DEPT VERTEBRATE PALEONTOL,CENT PK W & 79TH ST,NEW YORK,NY 10024, USA.
NR 8
TC 47
Z9 55
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 55
EP 58
DI 10.1038/369055a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000051
DA 2026-03-10
ER

PT J
AU SETH, A
   STERN, LJ
   OTTENHOFF, THM
   ENGEL, I
   OWEN, MJ
   LAMB, JR
   KLAUSNER, RD
   WILEY, DC
AF SETH, A
   STERN, LJ
   OTTENHOFF, THM
   ENGEL, I
   OWEN, MJ
   LAMB, JR
   KLAUSNER, RD
   WILEY, DC
TI BINARY AND TERNARY COMPLEXES BETWEEN T-CELL RECEPTOR, CLASS-II MHC AND SUPERANTIGEN IN-VITRO
SO NATURE
LA English
DT Article
ID antigen receptor; lymphocytes-t; enterotoxin-b; proteins; peptide; recognition; affinity; heterodimers; surface; anergy
AB SUPERANTIGENS are proteins that in association with class II major histocompatibility complex (MHC)-bearing cells can stimulate virtually all T cells that express particular classes of the variable beta-domains of the T-cell receptor (TCR)(1). This mechanism of T-cell activation circumvents the usual requirement for peptide-specific MHC recognition. Staphylococcus aureus enterotoxin B (SEB) is a bacterial superantigen that causes food poisoning and shock(2-5). We have characterized the tertiary complex of SEB, a soluble T-cell receptor, and a soluble class II MHC molecule DR1, and the three binary complexes TCR-SEB, SEB-DR1, and the peptide-specific complex DR1-TCR. We report here that in each case the specificity of the interaction among the soluble molecules is the same as observed in biological assays. Native gel electrophoresis and plasmon resonance affinity measurements indicate that SEB-TCR complex can form in the absence of class II MHC and that SEB-TCR interaction increases the binding of DR1. The observation that a superantigen can form complexes with TCR in both the absence and presence of class II MHC may provide a mechanism for its ability to induce anergy in some circumstances and activation in others(6,7) (reviewed in ref. 8).
C1 HARVARD UNIV,HOWARD HUGHES MED INST,CAMBRIDGE,MA 02138.
   NICHHD,CELL BIOL & METAB BRANCH,BETHESDA,MD 20892.
   IMPERIAL CANC RES FUND,LYMPHOCYTE MOLEC BIOL LAB,LONDON WC2A 3PX,ENGLAND.
   UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED,ST MARYS HOSP,SCH MED,DEPT IMMUNOL,LONDON W2 1PG,ENGLAND.
C3 Harvard University; Howard Hughes Medical Institute; National Institutes of Health (NIH) - USA; NIH Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD); Cancer Research UK; Imperial College London
RP SETH, A (corresponding author), HARVARD UNIV,DEPT BIOCHEM & MOLEC BIOL,7 DIVIN AVE,CAMBRIDGE,MA 02138, USA.
NR 26
TC 172
Z9 191
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 324
EP 327
DI 10.1038/369324a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900051
PM 8183371
DA 2026-03-10
ER

PT J
AU SALMELIN, R
   HARI, R
   LOUNASMAA, OV
   SAMS, M
AF SALMELIN, R
   HARI, R
   LOUNASMAA, OV
   SAMS, M
TI DYNAMICS OF BRAIN ACTIVATION DURING PICTURE NAMING
SO NATURE
LA English
DT Article
AB THE cerebral representation of language, deduced from observing patients with brain lesions and from stimulations and recordings performed during brain surgery1,2, has been further clarified by recent positron emission tomography3 and functional magnetic resonance imaging measurements4.  We now expand this static view into the dynamics of cortical activation using the accurate spatiotemporal resolution of whole-head magnetoencephalography5. During picture naming, the conversion from visual to symbolic representation progressed bilaterally from the occipital visual cortex towards temporal and frontal lobes. Overt naming elicited the most widespread cortical activation. Some language-related sites also reacted, though more weakly or after a longer delay, during covert naming and even passive viewing.
RP SALMELIN, R (corresponding author), HELSINKI UNIV TECHNOL,LOW TEMP LAB,SF-02150 ESPOO,FINLAND.
NR 9
TC 276
Z9 306
U1 0
U2 26
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 463
EP 465
DI 10.1038/368463a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000066
PM 8133893
DA 2026-03-10
ER

PT J
AU WIDAWSKI, G
   RAWISO, M
   FRANCOIS, B
AF WIDAWSKI, G
   RAWISO, M
   FRANCOIS, B
TI SELF-ORGANIZED HONEYCOMB MORPHOLOGY OF STAR-POLYMER POLYSTYRENE FILMS
SO NATURE
LA English
DT Article
ID polyparaphenylene
AB AN important challenge in the preparation of porous polymer membranes for technological applications is to control both the size distribution and the relative positions of the pores. We have found a way to generate polymer films with an essentially monodisperse pore size, in which the pores are organized spontaneously into periodic hexagonal arrays. The films, which are 10-30 mu m thick, are produced by evaporating solutions of star-shaped polystyrene or polystyrene-polyparaphenylene block copolymers in carbon disulphide under a flow of moist gas. Empty spherical cells, about 0.2-10 mu m in diameter, appear spontaneously in a hexagonal array, and the cells are open at the film surface. The use of star polymers, or of polymeric micelles, seems to be essential for obtaining this morphology. These membranes might find application in controlled release of drugs or other bioactive species, or as materials with useful optical properties, moulds or scaffolding for forming ordered microstructures, and model substrates for surface science.
C1 INST CHARLES SADRON,EAPH,CRM,F-67083 STRASBOURG,FRANCE.
NR 9
TC 1199
Z9 1312
U1 2
U2 405
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 387
EP 389
DI 10.1038/369387a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400052
DA 2026-03-10
ER

PT J
AU TSAI, FY
   KELLER, G
   KUO, FC
   WEISS, M
   CHEN, JZ
   ROSENBLATT, M
   ALT, FW
   ORKIN, SH
AF TSAI, FY
   KELLER, G
   KUO, FC
   WEISS, M
   CHEN, JZ
   ROSENBLATT, M
   ALT, FW
   ORKIN, SH
TI AN EARLY HEMATOPOIETIC DEFECT IN MICE LACKING THE TRANSCRIPTION FACTOR GATA-2
SO NATURE
LA English
DT Article
ID embryonic stem-cells; erythroid-differentiation; targeted mutation; developing mouse; dna-binding; yolk-sac; es cells; expression; gene; hematopoiesis
AB Blood cell development relies on the expansion and maintenance of haematopoietic stem and progenitor cells in the embryo. By gene targeting in mouse embryonic stem cells, we demonstrate that the transcription factor GATA-2 plays a critical role in haematopoiesis, particularly of an adult type. We propose that GATA-2 regulates genes controlling growth factor responsiveness or the proliferative capacity of early haematopoietic cells.
C1 CHILDRENS HOSP,DIV HEMATOL ONCOL,BOSTON,MA 02115.
   HARVARD UNIV,SCH MED,DANA FARBER CANC INST,DEPT PEDIAT,BOSTON,MA 02115.
   CHILDRENS HOSP,HOWARD HUGHES MED INST,BOSTON,MA 02115.
   HARVARD UNIV,SCH MED,DEPT GENET,BOSTON,MA 02115.
   BRIGHAM & WOMENS HOSP,CTR BLOOD RES,BOSTON,MA 02115.
   BRIGHAM & WOMENS HOSP,DEPT PATHOL,BOSTON,MA 02115.
   NATL JEWISH CTR IMMUNOL & RESP MED,DENVER,CO 80206.
C3 Harvard University; Harvard University Medical Affiliates; Boston Children's Hospital; Harvard University; Harvard University Medical Affiliates; Dana-Farber Cancer Institute; Harvard Medical School; Harvard University; Harvard University Medical Affiliates; Boston Children's Hospital; Howard Hughes Medical Institute; Harvard University; Harvard Medical School; Harvard University; Harvard University Medical Affiliates; Boston Children's Hospital; Program in Cellular & Molecular Medicine (PCMM); Brigham & Women's Hospital; Harvard University; Harvard University Medical Affiliates; Brigham & Women's Hospital; National Jewish Health
NR 39
TC 1230
Z9 1424
U1 0
U2 38
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 221
EP 226
DI 10.1038/371221a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000043
PM 8078582
DA 2026-03-10
ER

PT J
AU LI, R
   WAGA, S
   HANNON, GJ
   BEACH, D
   STILLMAN, B
AF LI, R
   WAGA, S
   HANNON, GJ
   BEACH, D
   STILLMAN, B
TI DIFFERENTIAL-EFFECTS BY THE P21 CDK INHIBITOR ON PCNA-DEPENDENT DNA-REPLICATION AND REPAIR
SO NATURE
LA English
DT Article
ID lagging strand synthesis; cell nuclear antigen; polymerase-delta; excision repair; auxiliary protein; invitro; kinases; p53; subunit; epsilon
AB IN mammalian cells, DNA damage increases the levels of the nuclear tumour-suppressor p53, resulting io elevated synthesis of p21, an inhibitor oi cyclin-dependent kinases (CDK)(1-6). p21 may also directly block DNA replication by inhibiting the proliferating-cell nuclear antigen (PCNA)(7), an essential DNA replication protein. However PCNA is also required for nucleotide-excision repair of DNA(8), an intrinsic part of the cellular response to ultraviolet irradiation. Using an in vitro system(9) we now show that p21 does not block PCNA-dependent nucleotide-excision repair, in contrast to its inhibition of simian virus 40 DNA replication(7) Furthermore, the short gap-filling DNA synthesis by PCNA-dependent DNA polymerases delta and epsilon is less sensitive to inhibition by p21 than is long primer-extension synthesis. The ability of p21 to inhibit the role of PCNA in DNA replication but not in DNA repair rationalizes in vivo data showing that genetic damage leads to inactivation of chromosomal replication while allowing damage-responsive repair.
RP LI, R (corresponding author), COLD SPRING HARBOR LAB,HOWARD HUGHES MED INST,POB 100,COLD SPRING HARBOR,NY 11724, USA.
NR 29
TC 645
Z9 707
U1 3
U2 82
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 534
EP 537
DI 10.1038/371534a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900061
PM 7935768
DA 2026-03-10
ER

PT J
AU MANDELBOIM, O
   BERKE, G
   FRIDKIN, M
   FELDMAN, M
   EISENSTEIN, M
   EISENBACH, L
AF MANDELBOIM, O
   BERKE, G
   FRIDKIN, M
   FELDMAN, M
   EISENSTEIN, M
   EISENBACH, L
TI CTL INDUCTION BY A TUMOR-ASSOCIATED ANTIGEN OCTAPEPTIDE DERIVED FROM A MURINE LUNG-CARCINOMA
SO NATURE
LA English
DT Article
ID viral peptides; lymphocytes-t; cells; gene; protein; recipients; rejection; lines
AB MANY mouse and human tumours express major histocompatibility complex (MHC) class I-associated antigens that constitute targets for syngeneic cytotoxic T lymphocytes (CTL). Genes encoding such antigens were isolated from a mouse mastocytoma and from human melanomas by genetic methods(1,2). Isolation and characterization of MHC class I-associated peptides has enabled specific anchor residues to be identified that are typical of peptides that bind to distinct class I molecules(3). Moreover, CTL specific to particular MHC-peptide combinations have been used to identify naturally occurring antigenic peptides in cell extracts and enabled them to be sequenced directly(4-6). Most known MHC ligands are of viral origin or are self peptides derived from normal proteins(7). Here we use total acid extraction and repeated fractionation to isolate and sequence Lewis lung carcinoma (3LL)-specific peptide(s), which shows sequence homology to the connexin 37 protein. Synthetic octamers based on these sequences bind to 'empty' H-2K(b) molecules on RMA-S cells, sensitize RMA-S cells to lysis by specific anti-3LL CTL, and induce anti-tumour CTL. The tumour-associated peptide originates from mutated connexin 37 expressed in 3LL.
C1 WEIZMANN INST SCI,DEPT CELL BIOL,IL-76100 REHOVOT,ISRAEL.
   WEIZMANN INST SCI,DEPT ORGAN CHEM,IL-76100 REHOVOT,ISRAEL.
   WEIZMANN INST SCI,DEPT BIOL STRUCT,IL-76100 REHOVOT,ISRAEL.
C3 Weizmann Institute of Science; Weizmann Institute of Science; Weizmann Institute of Science
NR 23
TC 259
Z9 279
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 67
EP 71
DI 10.1038/369067a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000055
PM 8164742
DA 2026-03-10
ER

PT J
AU YEO, JP
   ALDERUCCIO, F
   TOH, BH
AF YEO, JP
   ALDERUCCIO, F
   TOH, BH
TI A NEW CHROMOSOMAL PROTEIN ESSENTIAL FOR MITOTIC SPINDLE ASSEMBLY
SO NATURE
LA English
DT Article
ID cell-free-extracts; large t-antigen; xenopus eggs; microtubules; centrosm; components; lines
AB ASSEMBLY of the mitotic spindle, the machinery responsible for chromosomal segregation, is regulated by Cdc2 kinase1-5, and requires mitotic chromatin5-8. However, the molecular identity of the kinase substrate and chromatin factor is unknown. Here we have cloned a human complementary DNA encoding an evolutionarily conserved chromosomal protein of relative molecular mass 47,000 (M(r) 47K) which has three consensus motifs for Cdc2 kinase-mediated phosphorylation9. The protein is phosphorylated only during mitosis and is associated with polypeptides having M(r)s of 31K, 67K and 200K. Mitotic arrest is induced by antisense messenger RNA or by affinity-purified autoantibody. In the arrested cells, the chromosomes remain unsegregated and the mitotic spindle is absent. We propose that the chromosomal protein is activated by phosphorylation at the interphase/mitosis transition by Cdc2 kinase, and that the protein, alone or as a complex, is a previously unidentified Cdc2 kinase substrate and chromatin factor necessary for spindle assembly.
C1 MONASH UNIV,SCH MED,DEPT PATHOL & IMMUNOL,PRAHRAN,VIC 3181,AUSTRALIA.
C3 Monash University
NR 30
TC 25
Z9 26
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 288
EP 291
DI 10.1038/367288a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400061
PM 8121495
DA 2026-03-10
ER

PT J
AU MORGENBESSER, SD
   WILLIAMS, BO
   JACKS, T
   DEPINHO, RA
AF MORGENBESSER, SD
   WILLIAMS, BO
   JACKS, T
   DEPINHO, RA
TI P53-DEPENDENT APOPTOSIS PRODUCED BY RB-DEFICIENCY IN THE DEVELOPING MOUSE LENS
SO NATURE
LA English
DT Article
ID human papillomavirus type-16; wild-type p53; transgenic mice; cell-death; rat lens; gene; eye; transformation; keratinocytes; expression
AB THE retinoblastoma tumour-suppressor gene (RB) has been implicated in negative growth regulation, induction of differentiation, and inhibition of cellular transformation(1). Homozygous inactivation of the Rb gene in the mouse leads to mid-gestational lethality with defects in erythropoiesis and neurogenesis(2-4). Here we describe the effects of the Rb-deficient state on the development of the ocular lens. The regional compartmentalization of growth, differentiation and apoptosis in the developing lens provides an ideal system to examine more closely the relationships of these processes in vivo. We demonstrate that loss of Rb function is associated with unchecked proliferation, impaired expression of differentiation markers, and inappropriate apoptosis in lens fibre cells. In addition, we show that ectopic apoptosis in Rb-deficient lenses is dependent on p53, because embryos doubly null for Rb and p53 show a nearly complete suppression of this effect. This developmental system provides a framework for understanding the consequences of the frequent mutation of both RB and p53 in human cancer.
C1 MIT,CTR CANC RES,HOWARD HUGHES MED INST,CAMBRIDGE,MA 02139.
   MIT,DEPT BIOL,CAMBRIDGE,MA 02139.
   YESHIVA UNIV ALBERT EINSTEIN COLL MED,DEPT MICROBIOL & IMMUNOL,BRONX,NY 10461.
C3 Massachusetts Institute of Technology (MIT); Howard Hughes Medical Institute; Massachusetts Institute of Technology (MIT); Montefiore Medical Center; Albert Einstein College of Medicine; Yeshiva University
NR 28
TC 581
Z9 624
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 72
EP 74
DI 10.1038/371072a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100054
PM 8072529
DA 2026-03-10
ER

PT J
AU CLEMMER, DE
   SHELIMOV, KB
   JARROLD, MF
AF CLEMMER, DE
   SHELIMOV, KB
   JARROLD, MF
TI GAS-PHASE SELF-ASSEMBLY OF ENDOHEDRAL METALLOFULLERENES
SO NATURE
LA English
DT Article
ID carbon
AB METALLOFULLERENES1,2 consist of metal atoms trapped inside closed fullerene cages. Virtually nothing is known about the mechanism of metallofullerene synthesis, although the possibility of a condensed-phase mechanism has been suggested in recent studies3,4. Here we show that laser vaporization of a La2O3/graphite rod produces a number of LaC60+ isomers, including the endohedral metallofullerene and a variety of different isomers in which lanthanum seems to be bound to polycyclic polyyne rings. When heated, nearly all of the different ring isomers convert spontaneously into metallofullerenes, trapping the metal atom inside the fullerene cage with remarkably high efficiency (>98%). We suggest that in the first step of this annealing process the lanthanum atom acts as a nucleation centre and the carbon rings arrange themselves around the lanthanum atom before converting into a fullerene cage.
RP CLEMMER, DE (corresponding author), NORTHWESTERN UNIV,DEPT CHEM,2145 SHERIDAN RD,EVANSTON,IL 60208, USA.
NR 13
TC 44
Z9 45
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 718
EP 720
DI 10.1038/367718a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100052
DA 2026-03-10
ER

PT J
AU CLEMMER, DE
   HUNTER, JM
   SHELIMOV, KB
   JARROLD, MF
AF CLEMMER, DE
   HUNTER, JM
   SHELIMOV, KB
   JARROLD, MF
TI PHYSICAL AND CHEMICAL EVIDENCE FOR METALLOFULLERENES WITH METAL ATOMS AS PART OF THE CAGE
SO NATURE
LA English
DT Article
ID gas-phase; buckminsterfullerene; fullerenes; clusters; cations; ions
AB SINCE the discovery of fullerenes(1), efforts have been made to trap metal atoms inside fullerene cages(2), and both endohedral(3,4) and exohedral(5,6) metallofullerenes have been synthesized. There is, however, a third possibility: a 'networked' metallofullerene, where the metal atom is incorporated into the carbon cage. Here we report the results of experiments to study the structure and reactivity of gas-phase fullerenes doped with niobium (NbCn+ with n = 28-50). These experiments, which use injected-ion drift-tube techniques, indicate that for fullerenes containing an even number of carbon atoms the metal is endohedral, but for fullerenes with an odd number of carbon atoms, the niobium metal is bound as a part of the carbon cage. Thus, networked metallofullerenes appear to be a stable class of metallofullerene. We suggest that such metallofullerenes can form if the metal atom retains sufficient electron density to form several strong covalent metal-carbon bonds.
C1 NORTHWESTERN UNIV,DEPT CHEM,EVANSTON,IL 60208.
C3 Northwestern University
NR 23
TC 127
Z9 137
U1 0
U2 28
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 248
EP 250
DI 10.1038/372248a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900044
DA 2026-03-10
ER

PT J
AU HEBERLE, J
   RIESLE, J
   THIEDEMANN, G
   OESTERHELT, D
   DENCHER, NA
AF HEBERLE, J
   RIESLE, J
   THIEDEMANN, G
   OESTERHELT, D
   DENCHER, NA
TI PROTON MIGRATION ALONG THE MEMBRANE-SURFACE AND RETARDED SURFACE TO BULK TRANSFER
SO NATURE
LA English
DT Article
ID halobacterium-halobium; purple-membrane; bacteriorhodopsin; water; translocation; photocycle
AB Since the proposal of the chemiosmotic theory(1) there has been a continuing debate about how protons that have been pumped across membranes reach another membrane protein that utilizes the established pH gradient. Evidence has been gathered in favour of a 'delocalized' theory, in which the pumped protons equilibrate with the aqueous bulk phase before being consumed, and a 'localized' one, in which protons move exclusively along the membrane surface(2,3). We report here that after proton release by an integral membrane protein, long-range proton transfer along the membrane surface is faster than proton exchange with the bulk water phase. The rate of lateral proton diffusion can be calculated by considering the buffer capacity of the membrane surface. Our results suggest that protons can efficiently diffuse along the membrane surface between a source and a sink (for example H+-ATP synthase) without dissipation losses into the aqueous bulk.
C1 MAX PLANCK INST BIOCHEM, D-82152 MARTINSRIED, GERMANY.
   TH DARMSTADT, INST BIOCHEM, D-64287 DARMSTADT, GERMANY.
   HAHN MEITNER INST BERLIN GMBH, D-14109 BERLIN, GERMANY.
C3 Max Planck Society; Technical University of Darmstadt; Helmholtz Association; Helmholtz-Zentrum fuer Materialien und Energie GmbH (HZB)
NR 21
TC 311
Z9 336
U1 1
U2 53
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 379
EP 382
DI 10.1038/370379a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400058
PM 8047144
DA 2026-03-10
ER

PT J
AU FOTSIS, T
   ZHANG, YM
   PEPPER, MS
   ADLERCREUTZ, H
   MONTESANO, R
   NAWROTH, PP
   SCHWEIGERER, L
AF FOTSIS, T
   ZHANG, YM
   PEPPER, MS
   ADLERCREUTZ, H
   MONTESANO, R
   NAWROTH, PP
   SCHWEIGERER, L
TI THE ENDOGENOUS ESTROGEN METABOLITE 2-METHOXYOESTRADIOL INHIBITS ANGIOGENESIS AND SUPPRESSES TUMOR-GROWTH
SO NATURE
LA English
DT Article
ID metastasis; cells
AB THE formation of new blood vessels (angiogenesis) is critical for the growth of tumours(1-3) and is; a dominant feature in various angiogenic diseases such as diabetic retinopathy, arthritis, haemangiomas and psoriasis(4). Recognition of the potential therapeutic benefits of controlling pathological angiogenesis has led to a search for angiogenesis inhibitors. Here we report that 2-methoxyoestradiol, an endogenous oestrogen metabolite of previously unknown function, is a potent inhibitor of endothelial cell proliferation and migration as well as angiogenesis in vitro. Moreover, when administered orally in mice, it strongly inhibits the neovascularization of solid tumours and suppresses their growth. Unlike the angiostatic steroids of corticoid structure(5), it does not require the co-administration of heparin or sulphated cyclodextrins for activity. Thus, 2-methoxyoestradiol is the first steroid to have high antiangiogenic activity by itself. Our results suggest that this compound may have therapeutic potential in cancer and other angiogenic diseases.
C1 UNIV HEIDELBERG,DEPT MED & PATHOL,D-69120 HEIDELBERG,GERMANY.
   UNIV GENEVA,MED CTR,INST HISTOL & EMBRYOL,DEPT MORPHOL,CH-1121 GENEVA 4,SWITZERLAND.
   UNIV HELSINKI,MEILAHTI HOSP,DEPT CLIN CHEM,SF-00290 HELSINKI,FINLAND.
C3 Ruprecht Karls University Heidelberg; University of Geneva; University of Helsinki; Helsinki University Central Hospital
RP FOTSIS, T (corresponding author), UNIV HEIDELBERG,CHILDRENS UNIV HOSP,DEPT ONCOL & HAEMATOL,INF 150,D-69120 HEIDELBERG,GERMANY.
NR 15
TC 679
Z9 816
U1 0
U2 38
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 237
EP 239
DI 10.1038/368237a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000053
PM 7511798
DA 2026-03-10
ER

PT J
AU MINOR, DL
   KIM, PS
AF MINOR, DL
   KIM, PS
TI MEASUREMENT OF THE BETA-SHEET-FORMING PROPENSITIES OF AMINO-ACIDS
SO NATURE
LA English
DT Article
ID coil stability-constants; streptococcal protein-g; n-15 nmr; helix; tendency; water
AB SEVERAL model systems have been used to evaluate the alpha-helical propensities of different amino acids(1-7). In contrast, experimental quantitation of beta-sheet preferences has been addressed in only one model system, a zinc-finger peptide(8). Here we measure the relative propensity for beta-sheet formation of the twenty naturally occurring amino acids in a variant of the small, monomeric, beta-sheet-rich, IgG-binding domain from protein G. Amino-acid substitutions were made at a guest site on the solvent-exposed surface of the beta-sheet. Several criteria were used to establish that the mutations did not cause significant structural changes: binding to the Fc domain of IgG, calorimetric unfolding and NMR spectroscopy. Characterization of the thermal stabilities of these proteins leads to a thermodynamic scale for beta-sheet propensities that spans a range of similar to 2 kcal mol(-1) for the naturally occurring amino acids, excluding proline. The magnitude of the differences suggests that beta-sheet preferences can be important determinants of protein stability.
C1 MIT,HOWARD HUGHES MED INST,WHITEHEAD INST BIOMED RES,DEPT BIOL,CAMBRIDGE,MA 02142.
C3 Massachusetts Institute of Technology (MIT); Whitehead Institute; Howard Hughes Medical Institute
RP MINOR, DL (corresponding author), MIT,HOWARD HUGHES MED INST,WHITEHEAD INST BIOMED RES,DEPT CHEM,9 CAMBRIDGE CTR,CAMBRIDGE,MA 02142, USA.
NR 29
TC 577
Z9 688
U1 2
U2 90
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 660
EP 663
DI 10.1038/367660a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800059
PM 8107853
DA 2026-03-10
ER

PT J
AU VIDALE, JE
   ELLSWORTH, WL
   COLE, A
   MARONE, C
AF VIDALE, JE
   ELLSWORTH, WL
   COLE, A
   MARONE, C
TI VARIATIONS IN RUPTURE PROCESS WITH RECURRENCE INTERVAL IN A REPEATED SMALL EARTHQUAKE
SO NATURE
LA English
DT Article
ID stick-slip; california; friction; fault; creep; mechanism; rock
AB IN theory and in laboratory experiments, friction on sliding surfaces such as rock, glass and metal increases with time since the previous episode of slip1. This time dependence is a central pillar of the friction laws widely used to model earthquake phenomena2,3. On natural faults, other properties, such as rupture velocity4,5, porosity and fluid pressure6-11, may also vary with the recurrence interval. Eighteen repetitions of the same small earthquake, separated by intervals ranging from a few days to several years, allow us to test these laboratory predictions in situ. The events with the longest time since the previous earthquake tend to have about 15% larger seismic moment than those with the shortest intervals, although this trend is weak. In addition, the rupture durations of the events with the longest recurrence intervals are more than a factor of two shorter than for the events with the shortest intervals. Both decreased duration and increased friction are consistent with progressive fault healing during the time of stationary contact.
C1 MIT,DEPT EARTH ATMOSPHER & PLANETARY SCI,CAMBRIDGE,MA 02139.
C3 Massachusetts Institute of Technology (MIT)
RP VIDALE, JE (corresponding author), USGS,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA.
NR 27
TC 200
Z9 236
U1 0
U2 26
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 624
EP 626
DI 10.1038/368624a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200057
DA 2026-03-10
ER

PT J
AU NISWANDER, L
   JEFFREY, S
   MARTIN, GR
   TICKLE, C
AF NISWANDER, L
   JEFFREY, S
   MARTIN, GR
   TICKLE, C
TI A POSITIVE FEEDBACK LOOP COORDINATES GROWTH AND PATTERNING IN THE VERTEBRATE LIMB
SO NATURE
LA English
DT Article
ID apical ectodermal ridge; chick wing development; skeletal-muscle; retinoic acid; hox-4 genes; fgf family; bud cells; expression; mouse; outgrowth
AB LIMB development depends on signals from the apical ectodermal ridge and underlying mesenchyme(1,2). Fibroblast growth factor (FGF) can replace the ridge(3,4) and, because Fgf4 RNA is localized to the mouse posterior ridge(5), we proposed that FGF4 is the endogenous ridge signal(3). Ridge signals control limb outgrowth and maintain the zone of polarizing activity (ZPA) at the limb posterior margin(6), which is important in limb patterning: a ZPA graft to limb anterior mesenchyme causes cell respecification and mirror-image duplications(1,2). Sonic hedgehog (SHH7,8) has polarizing activity, and Shh RNA co-localizes with ZPA activity, suggesting SHH is the endogenous polarizing signal(7). We have investigated the molecular regulation of Fgf4 and Shh expression. We report here that Fgf4 expression in the ridge can be regulated by Shh-expressing cells. Moreover, Shh expression in mesenchyme can be activated by FGF4 in combination with retinoic acid. Once induced, Shh expression can be maintained by FGF4 alone, thus establishing a positive feedback loop between ZPA and ridge.
C1 UNIV CALIF SAN FRANCISCO,SCH MED,PROGRAM DEV BIOL,SAN FRANCISCO,CA 94143.
   MEM SLOAN KETTERING CANC CTR,PROGRAM MOLEC BIOL,NEW YORK,NY 10021.
   UNIV COLL & MIDDLESEX SCH MED,DEPT ANAT & DEV BIOL,LONDON W1P 6DB,ENGLAND.
C3 University of California System; University of California San Francisco; Memorial Sloan Kettering Cancer Center; University of London; University College London
RP NISWANDER, L (corresponding author), UNIV CALIF SAN FRANCISCO,SCH MED,DEPT ANAT,SAN FRANCISCO,CA 94143, USA.
NR 23
TC 632
Z9 714
U1 0
U2 28
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 609
EP 612
DI 10.1038/371609a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900053
PM 7935794
DA 2026-03-10
ER

PT J
AU HEIDELBERGER, R
   HEINEMANN, C
   NEHER, E
   MATTHEWS, G
AF HEIDELBERGER, R
   HEINEMANN, C
   NEHER, E
   MATTHEWS, G
TI CALCIUM-DEPENDENCE OF THE RATE OF EXOCYTOSIS IN A SYNAPTIC TERMINAL
SO NATURE
LA English
DT Article
ID squid giant synapse; neurotransmitter release; transmitter release; chromaffin cells; goldfish retina; bipolar cells; secretion; channels; influx; chelators
AB RAPID calcium-dependent exocytosis underlies neurotransmitter release from nerve terminals. Despite the fundamental importance of this process, neither the relationship between presynaptic intracellular calcium ion concentration ([Ca2+](i)) and rate of exocytosis, nor the maximal rate of secretion is known quantitatively. To provide this information, we have used flash photolysis of caged Ca2+ to elevate [Ca2+](i) rapidly and uniformly in synaptic terminals, while measuring membrane capacitance as ao index of exocytosis and monitoring [Ca2+](i) with a Ca2+-indicator dye. When [Ca2+](i) was abruptly increased to > 10 mu M, capacitance rose at a rate that increased steeply with [Ca2+](i). The steepness suggested that at least four calcium ions must bind to activate synaptic vesicle fusion. Half-saturation was at 194 mu M, and the maximal rate constant was 2,000-3,000 s(-1). A given synaptic vesicle can exocytose with high probability within a few hundred microseconds, if [Ca2+](i) rises above 100 mu M These properties provide for the extremely rapid signalling required for neuronal communication.
C1 SUNY STONY BROOK,DEPT NEUROBIOL & BEHAV,STONY BROOK,NY 11794.
C3 State University of New York (SUNY) System; Stony Brook University
RP HEIDELBERGER, R (corresponding author), MAX PLANCK INST BIOPHYS CHEM,MEMBRANBIOPHYS ABT,FASSBERG,W-3400 GOTTINGEN,GERMANY.
NR 30
TC 640
Z9 709
U1 1
U2 40
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 513
EP 515
DI 10.1038/371513a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900055
PM 7935764
DA 2026-03-10
ER

PT J
AU ZERR, A
   BOEHLER, R
AF ZERR, A
   BOEHLER, R
TI CONSTRAINTS ON THE MELTING TEMPERATURE OF THE LOWER MANTLE FROM HIGH-PRESSURE EXPERIMENTS ON MGO AND MAGNESIOWUSTITE
SO NATURE
LA English
DT Article
ID core; feo
AB THE melting temperatures of minerals in the Mg-Fe-Si-O-system play a fundamental role in the chemical differentiation, theology and geodynamics of the Earth's lower mantle. We have previously shown(1) that the melting curve of (Mg, Fe)SiO3-perovskite-the dominant mineral in the lower mantle-is extremely steep, implying melting temperatures at the bottom of the lower mantle in excess of 7,000 K. The large difference between actual mantle temperatures and the melting temperature inferred from our experiments suggests that the viscosity of the lower mantle is much larger than that typically used in convection models(2). Theoretical estimates of the melting temperature of MgO (refs 3-5) suggest even higher melting temperatures for (Mg, Fe)O-magnesiowustite, the second most abundant mineral in the lower mantle. We show here, however, that the melting curves of these two minerals are flat compared to the perovskite melting curve, thus lowering the upper bounds for the solidus in the lowermost mantle to about 5,000 K. This reduces the estimate of the viscosity to more realistic levels but still rules out large-scale melting in the lower mantle. Because magnesiowustite is slightly more dense than Mg-Fe-Si-perovskite due to iron partitioning, chemical segregation in the lower mantle cannot be excluded in regions where the local temperature exceeds the solidus.
RP ZERR, A (corresponding author), MAX PLANCK INST CHEM,POSTFACH 3060,D-55020 MAINZ,GERMANY.
NR 17
TC 191
Z9 210
U1 0
U2 29
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 506
EP 508
DI 10.1038/371506a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900052
DA 2026-03-10
ER

PT J
AU WEYAND I
   GODDE, M
   FRINGS, S
   WEINER, J
   MULLER, F
   ALTENHOFEN, W
   HATT, H
   KAUPP, UB
AF WEYAND, I
   GODDE, M
   FRINGS, S
   WEINER, J
   MULLER, F
   ALTENHOFEN, W
   HATT, H
   KAUPP, UB
TI CLONING AND FUNCTIONAL EXPRESSION OF A CYCLIC-NUCLEOTIDE-GATED CHANNEL FROM MAMMALIAN SPERM
SO NATURE
LA English
DT Article
ID olfactory epithelium; rod photoreceptors; ionic selectivity; excised patches; membrane; receptor; pores; cell; dna
AB CYCLIC nucleotide-gated (CNG) channels serve as downstream targets of signalling pathways in vertebrate photoreceptor cells and olfactory sensory neurons (see ref. 1 for review). Ca2+ ions that enter through CNG channels(2-5) intimately control these signalling pathways by regulating synthesis(6) or hydrolysis(7) of cyclic nucleotides, and by decreasing ligand sensitivity of CNG channels(8). Several lines of evidence suggest that cyclic nucleotides and Ca2+ play important roles in chemotaxis of invertebrate sperm and fertilization (see ref. 9 for review), whereas their mechanisms of action in vertebrate sperm are largely unknown. Here we report the cloning and functional expression of a novel CNG channel from bovine testis. The channel polypeptide was functionally localized in sperm, but is also specifically expressed in cone photoreceptor cells. These channels might be involved in chemotaxis of sperm by controlling Ca2+ entry through a cyclic-nucleotide signalling pathway.
C1 RUHR UNIV BOCHUM, INST PHYSIOL, D-44780 BOCHUM, GERMANY.
C3 Ruhr University Bochum
RP WEYAND I (corresponding author), FORSCHUNGSZENTRUM JULICH, INST BIOL INFORMAT VERARBEITUNG, POSTFACH 1913, D-52425 JULICH, GERMANY.
NR 30
TC 234
Z9 252
U1 0
U2 7
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 859
EP 863
DI 10.1038/368859a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700073
PM 7512693
DA 2026-03-10
ER

PT J
AU YOUVAN, DC
AF YOUVAN, DC
TI IMAGING SEQUENCE SPACE
SO NATURE
LA English
DT Article
ID molecular-biology; spectroscopy
RP YOUVAN, DC (corresponding author), PALO ALTO INST MOLEC MED,2462 WYANDOTTE ST,MT VIEW,CA 94043, USA.
NR 9
TC 26
Z9 37
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 79
EP 80
DI 10.1038/369079a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000059
PM 8164746
DA 2026-03-10
ER

PT J
AU BRUNNER, D
   DUCKER, K
   OELLERS, N
   HAFEN, E
   SCHOLZ, H
   KLAMBT, C
AF BRUNNER, D
   DUCKER, K
   OELLERS, N
   HAFEN, E
   SCHOLZ, H
   KLAMBT, C
TI THE ETS DOMAIN PROTEIN POINTED-P2 IS A TARGET OF MAP KINASE IN THE SEVENLESS SIGNAL-TRANSDUCTION PATHWAY
SO NATURE
LA English
DT Article
ID receptor tyrosine kinase; functions downstream; genetic dissection; drosophila eye; growth-factor; activation; expression; cells; localization; pattern
AB The fate of the R7 photoreceptor cell in the developing eye of Drosophila is controlled by the Sevenless (Sev) receptor tyrosine kinase(1,2). Sev activates a highly conserved signal transduction cascade involving the proteins Ras1 and Raf and the Rolled/mitogen-activated protein (Rl/hlAP) kinase(3). Here we show that the ETS domain protein encoded by the P2 transcript of the pointed (pnt) gene is a nuclear target of this signalling cascade which acts downstream of RI/MAP kinase. The PntP2 protein is phosphorylated by Rl/MAP kinase in vitro at a single site and this site is required for its function in vivo. Furthermore, we present genetic and biochemical data suggesting that MAP kinase controls neural development through phosphorylation of two antagonizing transcription factors of the ETS family, Yan and PntP2.
C1 UNIV ZURICH,INST ZOOL,CH-8057 ZURICH,SWITZERLAND.
   UNIV COLOGNE,INST ENTWICKLUNGSBIOL,D-50923 COLOGNE,GERMANY.
C3 University of Zurich; University of Cologne
NR 30
TC 330
Z9 372
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 386
EP 389
DI 10.1038/370386a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400060
PM 8047146
DA 2026-03-10
ER

PT J
AU JARDETZKY, TS
   BROWN, JH
   GORGA, JC
   STERN, LJ
   URBAN, RG
   CHI, YI
   STAUFFACHER, C
   STROMINGER, JL
   WILEY, DC
AF JARDETZKY, TS
   BROWN, JH
   GORGA, JC
   STERN, LJ
   URBAN, RG
   CHI, YI
   STAUFFACHER, C
   STROMINGER, JL
   WILEY, DC
TI 3-DIMENSIONAL STRUCTURE OF A HUMAN CLASS-II HISTOCOMPATIBILITY MOLECULE COMPLEXED WITH SUPERANTIGEN
SO NATURE
LA English
DT Article
ID staphylococcal enterotoxin-b; shock syndrome toxin-1; receptor beta-chain; high-affinity binding; t-cell recognition; hla-dr; v-beta; alpha; identification; polymorphism
AB The structure of a bacterial superantigen, Staphylococcus aureus enterotoxin B, bound to a human class II histocompatibility complex molecule (HLA-DR1) has been determined by X-ray crystallography. The superantigen binds as an intact protein outside the conventional peptide antigen-binding site of the class II major histocompatibility complex (MHC) molecule. No large conformational changes occur upon complex formation in either the DR1 or the enterotoxin B molecules. The structure of the complex helps explain how different class II molecules and superantigens associate and suggests a model for ternary complex formation with the T-cell antigen receptor (TCR), in which unconventional TCR-MHC contacts are possible.
C1 HARVARD UNIV, HOWARD HUGHES MED INST, DEPT BIOCHEM & MOLEC BIOL, CAMBRIDGE, MA 02138 USA.
   BRANDEIS UNIV, ROSENSTIEL BASIC MED SCI RES CTR, WALTHAM, MA 02154 USA.
   CHILDRENS HOSP PITTSBURGH, DEPT PEDIAT, PITTSBURGH, PA 15213 USA.
   PURDUE UNIV, DEPT BIOL, W LAFAYETTE, IN 47907 USA.
C3 Howard Hughes Medical Institute; Harvard University; Brandeis University; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh; Purdue University System; Purdue University
NR 65
TC 535
Z9 597
U1 0
U2 24
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 711
EP 718
DI 10.1038/368711a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300049
PM 8152483
DA 2026-03-10
ER

PT J
AU ARIAS, J
   ALBERTS, AS
   BRINDLE, P
   CLARET, FX
   SMEAL, T
   KARIN, M
   FERAMISCO, J
   MONTMINY, M
AF ARIAS, J
   ALBERTS, AS
   BRINDLE, P
   CLARET, FX
   SMEAL, T
   KARIN, M
   FERAMISCO, J
   MONTMINY, M
TI ACTIVATION OF CAMP AND MITOGEN RESPONSIVE GENES RELIES ON A COMMON NUCLEAR FACTOR
SO NATURE
LA English
DT Article
ID c-jun; transcriptional activation; phosphorylation; creb; fos; promoters; complex; kinase; domain; binds
AB A NUMBER of Signalling pathways stimulate transcription of target genes through nuclear factors whose activities are primarily regulated by phosphorylation. Cyclic AMP regulates the expression of numerous genes, for example, through the protein kinase-A (PKA)-mediated phosphorylation of transcription factor CREB at Ser133(1,2) Although phosphorylation may stimulate transcriptional activators by modulating their nuclear transport or DNA-binding affinity(3), CREB belongs to a class of proteins whose phosphorylation appears specifically to enhance their trans-activation potential(1,2,4). Recent work describing a phospho-CREB binding protein (CBP)(5) which interacts specifically with the CREB trans-activation domain prompted us to examine whether CBP is necessary for cAMP regulated transcription. We report here that microinjection of an anti-CBP antiserum into fibroblasts can inhibit transcription from a cAMP responsive promoter. Surprisingly, CBP also cooperates with upstream activators such as c-Jun, which are involved in mitogen responsive transcription(6). We propose that CBP is recruited to the promoter through interaction with certain phosphorylated factors, and that CBP may thus play a critical role in the transmission of inductive signals from cell surface receptor to the transcriptional apparatus.
C1 UNIV CALIF SAN DIEGO, DEPT MED, LA JOLLA, CA 92093 USA.
   UNIV CALIF SAN DIEGO, PROGRAM BIOMED SCI, LA JOLLA, CA 92093 USA.
   IMPERIAL CANC RES FUND, TRANSCRIPT LAB, LONDON WC2A 3PX, ENGLAND.
C3 University of California System; University of California San Diego; University of California System; University of California San Diego; Cancer Research UK
RP ARIAS, J (corresponding author), SALK INST BIOL STUDIES, CLAYTON FDN LABS PEPTIDE BIOL, 10010 N TORREY PINES RD, LA JOLLA, CA 92037 USA.
NR 21
TC 697
Z9 755
U1 0
U2 20
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 226
EP 229
DI 10.1038/370226a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100056
PM 8028671
DA 2026-03-10
ER

PT J
AU JARMAN, AP
   GRELL, EH
   ACKERMAN, L
   JAN, LY
   JAN, YN
AF JARMAN, AP
   GRELL, EH
   ACKERMAN, L
   JAN, LY
   JAN, YN
TI ATONAL IS THE PRONEURAL GENE FOR DROSOPHILA PHOTORECEPTORS
SO NATURE
LA English
DT Article
ID neuronal differentiation; neural development; nervous-system; visual-system; eye; retina; melanogaster; neurogenesis; expression; hedgehog
AB THE Drosophila peripheral nervous system comprises four major types of sensory element: external sense organs (such as mechanosensory bristles), chordotonal organs (internal stretch receptors), multiple dendritic neurons, and photoreceptors. During development, the selection of neural precursors for external sense organs requires the proneural genes of the achaete-scute complex, which encode basic-helix-loop-helix transcription factors(1-3). These genes do not, however, control precursor selection for chordotonal organs or photoreceptors(4,5), raising the question of whether other proneural genes exist(6) or a different mechanism of neurogenesis operates. Here we show that atonal (ato), originally isolated as a proneural gene for chordotonal organs(7), is also the proneural gene for photoreceptors. Pattern formation in the Drosophila eye involves a succession of cell fate specifications. Of the eight photoreceptors within each ommatidium of the compound eye, the photoreceptor R8 is the first to appear in the eye imaginal disc, right behind the morphogenetic furrow(8-10). The appearance of other photoreceptors (R1-7) follows in a defined sequence that is thought to arise by induction from R8 (refs 8, 9, 11, 12). We find that photoreceptor formation requires the function of atonal at the morphogenetic furrow and that atonal is specifically required for R8 selection. Formation of other photoreceptors does not directly require atonal function, but does depend on R8 selection by atonal. Thus, photoreceptors are selected by two mechanisms: R8 by a proneural mechanism, and R1-7 by local recruitment.
C1 UNIV CALIF SAN FRANCISCO,DEPT PHYSIOL,SAN FRANCISCO,CA 94143.
   UNIV CALIF SAN FRANCISCO,DEPT BIOCHEM,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco; University of California System; University of California San Francisco
RP JARMAN, AP (corresponding author), UNIV CALIF SAN FRANCISCO,HOWARD HUGHES MED INST,SAN FRANCISCO,CA 94143, USA.
NR 25
TC 432
Z9 515
U1 0
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 398
EP 400
DI 10.1038/369398a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400056
PM 8196767
DA 2026-03-10
ER

PT J
AU KWOK, RPS
   LUNDBLAD, JR
   CHRIVIA, JC
   RICHARDS, JP
   BACHINGER, HP
   BRENNAN, RG
   ROBERTS, SGE
   GREEN, MR
   GOODMAN, RH
AF KWOK, RPS
   LUNDBLAD, JR
   CHRIVIA, JC
   RICHARDS, JP
   BACHINGER, HP
   BRENNAN, RG
   ROBERTS, SGE
   GREEN, MR
   GOODMAN, RH
TI NUCLEAR-PROTEIN CBP IS A COACTIVATOR FOR THE TRANSCRIPTION FACTOR CREB
SO NATURE
LA English
DT Article
ID cyclic-amp; somatostatin gene; escherichia-coli; factor-tfiib; activation; element; binding; dna; phosphorylation; identification
AB THE transcription factor CREB binds to a DNA element known as the cAMP-regulated enhancer (CRE)(1-5). CREB is activated through phosphorylation by protein kinase A (PKA)(6), but precisely how phosphorylation stimulates CREB function is unknown. One model is that phosphorylation may allow the recruitment of coactivators which then interact with basal transcription factors. We have previously identified a nuclear protein of M(r) 265K, CBP, that binds specifically to the PKA-phosphorylated form of CREB(7). We have used fluorescence anisotropy measurements to define the equilibrium binding parameters of the phosphoCREB:CBP interaction and report here that CBP can activate transcription through a region in its carboxy terminus. The activation,domain of CBP interacts with the basal transcription factor TFIIB through a domain that is conserved in the yeast coactivator ADA-1 (ref. 8). Consistent with its role as a coactivator, CBP augments the activity of phosphorylated CREB to activate transcription of cAM-responsive genes.
C1 OREGON HLTH SCI UNIV,VOLLUM INST,PORTLAND,OR 97201.
   OREGON HLTH SCI UNIV,DEPT BIOCHEM,PORTLAND,OR 97201.
   ST LOUIS UNIV,DEPT PHARMACOL & PHYSIOL SCI,ST LOUIS,MO 63014.
   SHRINERS HOSP CRIPPLED CHILDRENS,PORTLAND,OR 97201.
   UNIV MASSACHUSETTS,MED CTR,PROGRAM MOLEC MED,WORCESTER,MA 01605.
C3 Oregon Health & Science University; Oregon Health & Science University; Saint Louis University; University of Massachusetts System; University of Massachusetts Worcester
NR 19
TC 1309
Z9 1454
U1 2
U2 66
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 223
EP 226
DI 10.1038/370223a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100055
PM 7913207
DA 2026-03-10
ER

PT J
AU KONDRASHOV, AS
AF KONDRASHOV, AS
TI THE ASEXUAL PLOIDY CYCLE AND THE ORIGIN OF SEX
SO NATURE
LA English
DT Article
ID cell-fusion; evolution; meiosis; ameba; dna; reproduction; gymnamoebia; selection; mutations; advantage
AB SEX involves syngamy (gamete fusion), which doubles the amount of DNA in a cell, and meiosis(1), which halves it. The result is a 'ploidy cycle' of alternating diploid and haploid phases. Asexual reproduction does not require changes of ploidy, and yet asexual forms may have ploidy cycles. Here I show that such cycles lessen the mutation load, compared with permanent diploidy or polyploidy, and are thus likely to evolve in cases where it is always advantageous to have more than one copy of the genome per cell. The asexual ploidy cycle could have facilitated the origin of sex, by providing a means of orderly genetic reduction available immediately after the origin of syngamy.
RP KONDRASHOV, AS (corresponding author), CORNELL UNIV,ECOL & SYSTEMAT SECT,ITHACA,NY 14853, USA.
NR 34
TC 80
Z9 93
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 213
EP 216
DI 10.1038/370213a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100051
PM 8028667
DA 2026-03-10
ER

PT J
AU SIEVERS, D
   VONKIEDROWSKI, G
AF SIEVERS, D
   VONKIEDROWSKI, G
TI SELF REPLICATION OF COMPLEMENTARY NUCLEOTIDE-BASED OLIGOMERS
SO NATURE
LA English
DT Article
ID hexadeoxynucleotide; systems; linkage; growth
AB THE development of non-enzymatic self-replicating systems based on autocatalytic template-directed reactions is a current objective of bioorganic chemistry(1-6). Typically, a self-complementary template molecule AB is synthesized autocatalytically from two complementary template fragments A and B7-16. Natural replication of nucleic acids, however, utilizes complementary rather than self-complementary strands. Here we report on a minimal implementation of this type of replication(17) based on cross-catalytic template-directed syntheses of hexadeoxynucleotide derivatives from amino-trideoxynucleotides. In our experiments, two self-complementary and two complementary templates compete for their combinatorial synthesis from four common trimeric precursors. We provide kinetic evidence that cross-catalytic self-replication of complementary templates can proceed with an efficiency similar to that of autocatalytic self-replication of self-complementary templates. We observe selective stimulation of template synthesis, and thus information transfer, on seeding the reaction mixtures with one of four chemically labelled templates bearing the sequence of the reaction products. Our results bring a stage closer the development of schemes that might explain how replicating systems based on nucleic acids arose on the prebiotic Earth.
C1 UNIV FREIBURG,DEPT ORGAN CHEM & BIOCHEM,D-79104 FREIBURG,GERMANY.
C3 University of Freiburg
NR 25
TC 389
Z9 426
U1 1
U2 42
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 221
EP 224
DI 10.1038/369221a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700052
PM 8183342
DA 2026-03-10
ER

PT J
AU SHANNON, PJ
   GIBBONS, WM
   SUN, ST
AF SHANNON, PJ
   GIBBONS, WM
   SUN, ST
TI PATTERNED OPTICAL-PROPERTIES IN PHOTOPOLYMERIZED SURFACE-ALIGNED LIQUID-CRYSTAL FILMS
SO NATURE
LA English
DT Article
ID polarized laser-light; alignment
AB MOST practical applications of liquid crystals require control of molecular alignment at macroscopic scales1. This is achieved most simply by confining the liquid-crystalline phase between mechanically rubbed surfaces1. Recent developments2-11 have shown that liquid-crystal alignment can also be controlled by optical means: for example, if azo dyes either on the alignment surface2,3,5,8-11 or dispersed within the liquid crystal itself4,6,7 are oriented by illumination with polarized light, alignment can be induced in the liquid crystal. We show here that the high-resolution alignment patterns obtainable by such techniques may be 'frozen in' by subsequent photopolymerization of the optically patterned liquid-crystalline phase. The resulting polymer films might prove valuable in the development of high-density optical storage media, three-dimensional stereo displays and other optical devices.
RP SHANNON, PJ (corresponding author), HERCULES INC,RES CTR,WILMINGTON,DE 19808, USA.
NR 16
TC 249
Z9 285
U1 0
U2 40
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 532
EP 533
DI 10.1038/368532a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500049
DA 2026-03-10
ER

PT J
AU COULSON, D
   FERREIRA, P
   GRAHAM, P
   TUROK, N
AF COULSON, D
   FERREIRA, P
   GRAHAM, P
   TUROK, N
TI MICROWAVE ANISOTROPIES FROM COSMIC DEFECTS
SO NATURE
LA English
DT Article
ID string evolution; flat spacetime
AB High-resolution maps of the temperature fluctuations in the cosmic microwave background radiation will provide valuable insight into the mechanism of structure formation in the early Universe. Theories involving Inflation generally predict a pattern of gaussian (random) noise, whereas theories based on symmetry breaking and the generation of defects-such as strings; textures and monopoles-have more distinctive signatures. Degree-scale measurements of the microwave background currently in progress should provide a powerful test of these competing theories.
C1 IMPERIAL COLL SCI TECHNOL & MED,BLACKETT LAB,LONDON SW7 2BZ,ENGLAND.
C3 Imperial College London
RP COULSON, D (corresponding author), PRINCETON UNIV,JOSEPH HENRY LABS,PRINCETON,NJ 08544, USA.
NR 23
TC 85
Z9 85
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 27
EP 31
DI 10.1038/368027a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900043
DA 2026-03-10
ER

PT J
AU FOLEY, JA
   KUTZBACH, JE
   COE, MT
   LEVIS, S
AF FOLEY, JA
   KUTZBACH, JE
   COE, MT
   LEVIS, S
TI FEEDBACKS BETWEEN CLIMATE AND BOREAL FORESTS DURING THE HOLOCENE EPOCH
SO NATURE
LA English
DT Article
ID tropical deforestation; simulations; yukon
AB PREVIOUS studies(1-5) have demonstrated that the predictions of global climate models are highly sensitive to large changes in vegetation cover, such as the complete removal of tropical or boreal forests. Although these studies have illustrated the potential effects of massive deforestation on the climate system, vegetation changes of this scale are very unlikely to occur. Investigating past environments may better illustrate the possible interactions between climate and vegetation cover. For example, palaeobotanical evidence indicates that 6,000 years ago boreal forests extended north of the modern treeline(6), apparently in response to high-latitude warming resulting from variations in the Earth's orbit(7,8). The expanded boreal forests, which took the place of tundra, must also have affected climate by significantly reducing the surface albedo(5). Here we use a global climate model to examine the relative effects of orbitally-induced insolation variations and of the northward extension of boreal forests on the mid-Holocene climate. Orbital variations alone warm the high latitudes by 2 degrees C or more in summer, autumn and winter. The subsequent northward extension of boreal forests gives rise to an additional warming of approximately 4 degrees C in spring and about 1 degrees C in the other seasons. This suggests that large positive feedbacks between climate and boreal forests may have taken place in the recent geological past.
C1 UNIV WISCONSIN,DEPT ATMOSPHER & OCEAN SCI,MADISON,WI 53706.
C3 University of Wisconsin System; University of Wisconsin Madison
RP FOLEY, JA (corresponding author), UNIV WISCONSIN,INST ENVIRONM STUDIES,1225 W DAYTON ST,MADISON,WI 53706, USA.
NR 23
TC 390
Z9 436
U1 0
U2 82
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 52
EP 54
DI 10.1038/371052a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100046
DA 2026-03-10
ER

PT J
AU FRENKLACH, M
   SKOKOV, S
   WEINER, B
AF FRENKLACH, M
   SKOKOV, S
   WEINER, B
TI AN ATOMISTIC MODEL FOR STEPPED DIAMOND GROWTH
SO NATURE
LA English
DT Article
ID chemical vapor-deposition; low-pressure; surface; dependence; films
AB The growth of many crystalline materials occurs through lateral propagation of steps over the surface(1-3). A stepped texture is also characteristic of diamond grown by chemical vapour deposition (CVDM)(4-10). Diffusion of atoms on the surface is usually held responsible for the stepped growth of metals, but it has been thought(11-14) that the stronger bonding of adatoms should prevent this mechanism from operating in the case of diamond. Recent experiments(15) have, however, indicated that surface diffusion can take place during diamond growth. We have recently shown theoretically(16) that bridging methylene (CH2) groups on the {100} plane of diamond growing in the presence of hydrogen can migrate in a manner equivalent to surface diffusion. Here we show that this theoretical picture can be developed into an atomistic model that accounts for stepped growth of diamond. The stepped pattern can be understood in terms of the formation of surface-bound species from the gaseous precursors, followed by their migration by means of a series of surface chemical reactions involving covalent bond breaking and formation.
C1 PENN STATE UNIV,DEPT PHYS,DU BOIS,PA 15801.
C3 Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University
RP FRENKLACH, M (corresponding author), PENN STATE UNIV,DEPT MAT SCI & ENGN,UNIVERSITY PK,PA 16802, USA.
NR 23
TC 46
Z9 48
U1 1
U2 24
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 535
EP 537
DI 10.1038/372535a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200047
DA 2026-03-10
ER

PT J
AU STEMMER, WPC
AF STEMMER, WPC
TI RAPID EVOLUTION OF A PROTEIN IN-VITRO BY DNA SHUFFLING
SO NATURE
LA English
DT Article
ID searching sequence space; spectrum beta-lactamases; molecular evolution; ensemble mutagenesis
AB DNA shuffling is a method for in vitro homologous recombination of pools of selected mutant genes by random fragmentation and polymerase chain reaction (PCR) reassembly(1). Computer simulations called genetic algorithms(2-4) have demonstrated the importance of iterative homologous recombination for sequence evolution. Oligonucleotide cassette mutagenesis(5-11) and error-prone PCR are not combinatorial and thus are limited in searching sequence space(1,14). We have tested mutagenic DNA shuffling for molecular evolution(14-18) in a beta-lactamase model system(9,19). Three cycles of shuffling and two cycles of backcrossing with wild-type DNA, to eliminate non-essential mutations, were each followed by selection on increasing concentrations of the antibiotic cefotaxime. We report here that selected mutants had a minimum inhibitory concentration of 640 mu g ml(-1), a 32,000-fold increase and 64-fold greater than any published TEM-1 derived enzyme. Cassette mutagenesis and error-prone PCR resulted in only a 16-fold increase(9).
RP STEMMER, WPC (corresponding author), AFFYMAX RES INST,4001 MIRANDA AVE,PALO ALTO,CA 94304, USA.
NR 22
TC 1546
Z9 2985
U1 9
U2 449
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 389
EP 391
DI 10.1038/370389a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400061
PM 8047147
DA 2026-03-10
ER

PT J
AU FREEDMAN, WL
   MADORE, BF
   MOULD, JR
   HILL, R
   FERRARESE, L
   KENNICUTT, RC
   SAHA, A
   STETSON, PB
   GRAHAM, JA
   FORD, H
   HOESSEL, JG
   HUCHRA, J
   HUGHES, SM
   ILLINGWORTH, GD
AF FREEDMAN, WL
   MADORE, BF
   MOULD, JR
   HILL, R
   FERRARESE, L
   KENNICUTT, RC
   SAHA, A
   STETSON, PB
   GRAHAM, JA
   FORD, H
   HOESSEL, JG
   HUCHRA, J
   HUGHES, SM
   ILLINGWORTH, GD
TI DISTANCE TO THE VIRGO CLUSTER GALAXY M100 FROM HUBBLE-SPACE-TELESCOPE OBSERVATIONS OF CEPHEIDS
SO NATURE
LA English
DT Article
ID measuring extragalactic distances; rr lyrae stars; absolute magnitudes; standard candles; ia supernovae; scale; constant; motion; velocity; supercluster
AB Accurate distances to galaxies are critical for determining the present expansion rate of the Universe or Hubble constant (H-o). An important step in resolving the current uncertainty in H-o is the measurement of the distance to the Virgo cluster of galaxies. New observations using the Hubble Space Telescope yield a distance of 17.1 +/- 1.8 Mpc to the Virgo cluster galaxy M100. This distance leads to a value of H-o = 80 +/- 17 km s(-1) Mpc(-1). A comparable value of H-o is also derived from the Coma cluster using independent estimates of its distance ratio relative to the Virgo cluster.
C1 CALTECH, JET PROP LAB, CTR INFRARED PROC & ANAL, NASA IPAC EXTRAGALACT DATABASE, PASADENA, CA 91125 USA.
   AUSTRALIAN NATL UNIV, MT STROMLO & SIDING SPRING OBSERV, WESTON, ACT 2611, AUSTRALIA.
   JOHNS HOPKINS UNIV, DEPT PHYS & ASTRON, BALTIMORE, MD 21218 USA.
   UNIV ARIZONA, STEWARD OBSERV, TUCSON, AZ 85721 USA.
   SPACE TELESCOPE SCI INST, BALTIMORE, MD 21218 USA.
   DOMINION ASTROPHYS OBSERV, VICTORIA V8X 4M6, BC, CANADA.
   CARNEGIE INST WASHINGTON, DEPT TERR MAGNETISM, WASHINGTON, DC 20015 USA.
   UNIV WISCONSIN, DEPT ASTRON, MADISON, WI 53706 USA.
   HARVARD SMITHSONIAN CTR ASTROPHYS, CAMBRIDGE, MA 02138 USA.
   ROYAL GREENWICH OBSERV, CAMBRIDGE CB3 0HA, ENGLAND.
   UNIV CALIF SANTA CRUZ, LICK OBSERV, SANTA CRUZ, CA 95064 USA.
C3 National Aeronautics & Space Administration (NASA); NASA Jet Propulsion Laboratory (JPL); California Institute of Technology; Australian National University; Johns Hopkins University; University of Arizona; Space Telescope Science Institute; National Research Council Canada; Carnegie Institution for Science; University of Wisconsin System; University of Wisconsin Madison; Smithsonian Astrophysical Observatory; Smithsonian Institution; Harvard University; University of Cambridge; University of California System; University of California Santa Cruz
RP FREEDMAN, WL (corresponding author), CARNEGIE INST WASHINGTON OBSERV, 813 SANTA BARBARA ST, PASADENA, CA 91101 USA.
NR 51
TC 406
Z9 418
U1 0
U2 15
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 757
EP 762
DI 10.1038/371757a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800048
DA 2026-03-10
ER

PT J
AU CAVA, RJ
   ZANDBERGEN, HW
   BATLOGG, B
   EISAKI, H
   TAKAGI, H
   KRAJEWSKI, JJ
   PECK, WF
   GYORGY, EM
   UCHIDA, S
AF CAVA, RJ
   ZANDBERGEN, HW
   BATLOGG, B
   EISAKI, H
   TAKAGI, H
   KRAJEWSKI, JJ
   PECK, WF
   GYORGY, EM
   UCHIDA, S
TI SUPERCONDUCTIVITY IN LANTHANUM NICKEL BORO-NITRIDE
SO NATURE
LA English
DT Article
AB RESEARCH into intermetallic superconductors has recently been reinvigorated by the discovery of superconductivity at 23 K in a Y-Pd-B-C quaternary alloy(1) (tying with the long-standing intermetallic record held by Nb-3 Ge (ref. 2)), and at lower temperatures in other quaternary boro-carbide alloys based on Ni, Pd and Pt3-6. The crystal structure of these new intermetallic superconductors, typified by LuNi2B2C (ref. 7), consists of one square layer of rock-salt-type LnC (where Ln stands for a rare-earth element) alternating with one layer of transition-metal boride tetrahedra. Here we report superconductivity at 12-13 K in a new quaternary intermetallic system, lanthanum nickel boro-nitride. We have determined the formula and crystal structure of superconducting La3Ni2B2N3, and also of a related non-superconducting phase LaNiBN. The crystal structure of La3Ni2B2N3 is related to that of LuNi2B2C, but consists of three rock-salt-type LaN layers alternating with tetrahedral Ni2B2 layers, an arrangement considerably more two-dimensional than is found for the superconducting boro-carbides. These discoveries strongly suggest that a large number of unusual superconducting intermetallic phases are get to be found, based on materials more complex than have previously been considered as candidates for superconductivity.
C1 DELFT INST TECHNOL,NATL CTR HIGH RESOLUT ELECTRON MICROSCOPY,DELFT,NETHERLANDS.
   UNIV TOKYO,DEPT APPL PHYS,TOKYO 113,JAPAN.
   UNIV TOKYO,INST SOLID STATE PHYS,TOKYO,JAPAN.
C3 Delft University of Technology; University of Tokyo; University of Tokyo
RP CAVA, RJ (corresponding author), AT&T BELL LABS,600 MT AVE,MURRAY HILL,NJ 07974, USA.
NR 9
TC 105
Z9 110
U1 2
U2 50
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 245
EP 247
DI 10.1038/372245a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900043
DA 2026-03-10
ER

PT J
AU ROUSSEAU, F
   BONAVENTURE, J
   LEGEAIMALLET, L
   PELET, A
   ROZET, JM
   MAROTEAUX, P
   LEMERRER, M
   MUNNICH, A
AF ROUSSEAU, F
   BONAVENTURE, J
   LEGEAIMALLET, L
   PELET, A
   ROZET, JM
   MAROTEAUX, P
   LEMERRER, M
   MUNNICH, A
TI MUTATIONS IN THE GENE ENCODING FIBROBLAST GROWTH-FACTOR RECEPTOR-3 IN ACHONDROPLASIA
SO NATURE
LA English
DT Article
ID birth prevalence rates; terminal differentiation; skeletal dysplasias; signal transduction; family
AB ACHONDROPLASIA, the most common cause of chondrodysplasia in man (1 in 15,000 live births), is a condition of unknown origin characterized by short-limbed dwarfism and macrocephaly(1,2). More than 90% of cases are sporadic and there is an increased paternal age at the time of conception of affected individuals, suggesting that de novo mutations are of paternal origin. Affected individuals are fertile and achondroplasia is transmitted as a fully penetrant autosomal dominant trait, accounting for rare familial forms of the disease (10%)(3-6). In contrast, homozygous achondroplasia is usually lethal in the neonatal period and affects 25% of the offspring of matings between heterozygous achondroplasia parents. The gene responsible for achondroplasia has been mapped to chromosome 4p16.3 (refs 7, 8); the genetic interval encompassing the disease gene contains a member of the fibroblast-growth-factor receptor (FGFR(3)) family which is expressed in articular chondrocytes. Here we report the finding of recurrent missense mutations in a CpG doublet of the transmembrane domain of the FGFR(3) protein (glycine substituted with arginine at residue 380, G380R) in 17 sporadic cases and 6 unrelated familial forms of achondroplasia. We show that the mutant genotype segregates with the disease in these families. Thus it appears that recurrent mutations of a single amino acid in the transmembrane domain of the FGFR(3) protein account for all cases (23/23) of achondroplasia in our series.
C1 HOP NECKER ENFANTS MALAD, INST NECKER, CNRS, ER 88, INSERM, U393, SERV GENET, F-75743 PARIS 15, FRANCE.
   HOP NECKER ENFANTS MALAD, INST NECKER,CNRS,ER 88,INSERM, U393,UNITE RECH HANDICAPS GENET ENFANT, F-75743 PARIS 15, FRANCE.
C3 Universite Paris Cite; Centre National de la Recherche Scientifique (CNRS); Assistance Publique Hopitaux Paris (APHP); Hopital Universitaire Necker-Enfants Malades - APHP; Institut National de la Sante et de la Recherche Medicale (Inserm); Centre National de la Recherche Scientifique (CNRS); Assistance Publique Hopitaux Paris (APHP); Universite Paris Cite; Hopital Universitaire Necker-Enfants Malades - APHP; Institut National de la Sante et de la Recherche Medicale (Inserm)
NR 18
TC 731
Z9 839
U1 0
U2 43
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 252
EP 254
DI 10.1038/371252a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000054
PM 8078586
DA 2026-03-10
ER

PT J
AU KESSON, SE
   FITZ GERALD, JD
   SHELLEY, JMG
AF KESSON, SE
   FITZ GERALD, JD
   SHELLEY, JMG
TI MINERAL CHEMISTRY AND DENSITY SUBDUCTED BASALTIC CRUST AT LOWER-MANTLE PRESSURES
SO NATURE
LA English
DT Article
ID phase-transformations; oceanic-crust; model
AB SUBDUCTED slabs are less dense than the surrounding mantle near the base of the transition zone (similar to 660 km depth) because of the survival of garnet in former basaltic crust: by this depth mantle peridotite has transformed to denser perovskitite(1,2). The buoyancy of the former basaltic crust may contribute to the observed accumulation or horizontal displacement of many slabs at the base of the transition zone(3). Here we report experimental confirmation of the widely held belief that the basaltic crust of slabs eventually transforms to a dense perovskititic lithology, stable in the lower mantle. Synthetic mid-ocean-ridge basalt (MORB) glass subjected to pressures of 45, 80 and 100 GPa in a laser-heated diamond anvil cell transforms to an assemblage of aluminous Mg,Fe silicate perovskite, non-quenchable CaSiO3 perovskite, stishovite and a sodic, aluminous phase with the Ca-ferrite structure (Fig. 1). Perovskititic MORB is about 0.06 g cm(-3) more dense than a model lower mantle (PREM) derived from seismological data. Thus even thermally equilibrated perovskititic slabs should encounter no significant hindrance to subduction and convection in the lower mantle.
RP KESSON, SE (corresponding author), AUSTRALIAN NATL UNIV, RES SCH EARTH SCI, GPO BOX 4, CANBERRA, ACT 0200, AUSTRALIA.
NR 28
TC 150
Z9 165
U1 0
U2 26
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 767
EP 769
DI 10.1038/372767a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200049
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI RESISTING THE TRADITIONS OF THE CENTER
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 795
EP 795
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700028
DA 2026-03-10
ER

PT J
AU SELLWOOD, BW
   PRICE, GD
   VALDES, PJ
AF SELLWOOD, BW
   PRICE, GD
   VALDES, PJ
TI COOLER ESTIMATES OF CRETACEOUS TEMPERATURES
SO NATURE
LA English
DT Article
ID planktonic-foraminifera; climates; belemnites; signals; isotope; ocean
AB THE Creataceous period is thought to have been warmer than the present(1-3), with higher concentrations of atmospheric greenhouse gases such as carbon dioxide(4). It has therefore been suggested(5) that this time period could be used by modellers as an analogue for future climate change. But the Cretaceous Equator-to-Pole temperature gradient was flatter than today's, leading some to suggest that Cretaceous climate arose from a combination of factors, with higher atmospheric carbon dioxide concentrations leading to general warming, and other factors, such as increased ocean heat transport, leading to flattening of the latitudinal temperature gradient. Here we report new records of ocean palaeotemperature for Cenomanian sites in the Atlantic and Pacific oceans which, together with a re-evaluation of published data, cast doubt on the idea that the Cretaceous period was generally warmer. These data confirm that the latitudinal temperature gradient was flatter, but suggest that the global mean temperature,vas much cooler than previously believed, with minimum mean equatorial temperatures close to present values and polar temperatures close to 0 degrees C. In the light of these findings, the climatic role of atmospheric carbon dioxide in determining Cretaceous climate is unclear, suggesting that the Cretaceous cannot be used as an analogue for future climate change.
C1 UNIV READING,DEPT METEOROL,READING RG6 2AU,BERKS,ENGLAND.
C3 University of Reading
RP SELLWOOD, BW (corresponding author), UNIV READING,POSTGRAD RES INST SEDIMENTOL,WHITEKNIGHTS,READING RG6 2AB,BERKS,ENGLAND.
NR 38
TC 123
Z9 133
U1 0
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 453
EP 455
DI 10.1038/370453a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700054
DA 2026-03-10
ER

PT J
AU BROWN, EJ
   ALBERS, MW
   SHIN, TB
   ICHIKAWA, K
   KEITH, CT
   LANE, WS
   SCHREIBER, SL
AF BROWN, EJ
   ALBERS, MW
   SHIN, TB
   ICHIKAWA, K
   KEITH, CT
   LANE, WS
   SCHREIBER, SL
TI A MAMMALIAN PROTEIN TARGETED BY G1-ARRESTING RAPAMYCIN-RECEPTOR COMPLEX
SO NATURE
LA English
DT Article
ID p70 s6 kinase; immunosuppressant rapamycin; induced inhibition; lymphocytes-t; yeast; immunophilin; activation; arrest; fk506; proliferation
AB THE structurally related natural products rapamycin and FK506 bind to the same intracellular receptor, FKBP12, yet the resulting complexes interfere with distinct signalling pathways(1,2). FKBP12- rapamycin inhibits progression through the G1 phase of the cell cycle in osteosarcoma(3), liver(4,5) and T cells(6,7) as well as in yeasts, and interferes with mitogenic signalling pathways that are involved in G1 progressiong(9,10), namely with activation of the protein p70(S6k) (refs 5, 11-13) and cyclin-dependent kinases(3,14-16). Here we isolate a mammalian FKBP-rapamycin-associated protein (FRAP) whose binding to structural variants of rapamycin complexed to FKBP12 correlates with the ability of these ligands to inhibit cell-cycle progression. Peptide sequences from purified bovine FRAP were used to isolate a human cDNA clone that is highly related to the DRR1/TOR1 and DRR2/TOR2 gene products from Saccharomyces cerevisiae(8,17,18). Although it has not been previously demonstrated that either of the DRR/TOR gene products can bind the FKBP-rapamycin complex directly(17,19), these yeast genes have been genetically linked to a rapamycin-sensitive pathway and are thought to encode lipid kinases(17-20).
C1 HARVARD UNIV,HOWARD HUGHES MED INST,DEPT CHEM,CAMBRIDGE,MA 02138.
   HARVARD UNIV,HARVARD MICROCHEM FACIL,CAMBRIDGE,MA 02138.
C3 Harvard University; Howard Hughes Medical Institute; Harvard University
NR 27
TC 1730
Z9 2169
U1 3
U2 166
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 756
EP 758
DI 10.1038/369756a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100064
PM 8008069
DA 2026-03-10
ER

PT J
AU MCGEEHAN, GM
   BECHERER, JD
   BAST, RC
   BOYER, CM
   CHAMPION, B
   CONNOLLY, KM
   CONWAY, JG
   FURDON, P
   KARP, S
   KIDAO, S
   MCELROY, AB
   NICHOLS, J
   PRYZWANSKY, KM
   SCHOENEN, F
   SEKUT, L
   TRUESDALE, A
   VERGHESE, M
   WARNER, J
   WAYS, JP
AF MCGEEHAN, GM
   BECHERER, JD
   BAST, RC
   BOYER, CM
   CHAMPION, B
   CONNOLLY, KM
   CONWAY, JG
   FURDON, P
   KARP, S
   KIDAO, S
   MCELROY, AB
   NICHOLS, J
   PRYZWANSKY, KM
   SCHOENEN, F
   SEKUT, L
   TRUESDALE, A
   VERGHESE, M
   WARNER, J
   WAYS, JP
TI REGULATION OF TUMOR-NECROSIS-FACTOR-ALPHA PROCESSING BY A METALLOPROTEINASE INHIBITOR
SO NATURE
LA English
DT Article
ID murine tumor; mono mac-6; activation; expression; secretion; cloning
AB TUMOUR necrosis factor-alpha (TNF-alpha) is a potent pro-inflammatory agent produced primarily by activated monocytes and macrophages(1). TNF-alpha is synthesized as a precursor protein of M(r) 26,000 (26K) which is processed to a secreted 17K mature form by cleavage of an Ala-Val bond between residues 76-77. The enzyme(s) responsible for processing pro-TNF-alpha has yet to be identified. Here, we describe the capacity of a metalloproteinase inhibitor, GI 129471, to block TNF-alpha secretion both in vitro and in vivo. The inhibition is specific to TNF-alpha; the production of other secreted cytokines, such as the interleukins IL-1 beta, IL-2, or IL-6, is not inhibited. The mechanism of inhibition occurs at a post-translational step in TNF-alpha production. Our data suggest that TNF-alpha processing is mediated by a unique Zn2+ endopeptidase which is inhibited by GI 129471 and would represent a novel target for therapeutic intervention in TNF-alpha associated pathologies.
C1 DUKE UNIV,MED CTR,DUKE COMPREHENS CANC CTR,DEPT MED,DURHAM,NC 27710.
   MCGILL UNIV,JEWISH GEN HOSP,DEPT ONCOL,MONTREAL H3T 1E2,PQ,CANADA.
   UNIV N CAROLINA,SCH MED,DEPT PATHOL,CHAPEL HILL,NC 27516.
C3 Duke University; Jewish General Hospital - Montreal; McGill University; University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina School of Medicine
RP MCGEEHAN, GM (corresponding author), GLAXO INC,RES INST,RES TRIANGLE PK,NC 27709, USA.
NR 26
TC 550
Z9 637
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 558
EP 561
DI 10.1038/370558a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700055
PM 8052311
DA 2026-03-10
ER

PT J
AU ORTMANN, B
   ANDROLEWICZ, MJ
   CRESSWELL, P
AF ORTMANN, B
   ANDROLEWICZ, MJ
   CRESSWELL, P
TI MHC CLASS I/BETA(2)-MICROGLOBULIN COMPLEXES ASSOCIATE WITH TAP TRANSPORTERS BEFORE PEPTIDE BINDING
SO NATURE
LA English
DT Article
ID class-i molecules; hla class-i; endoplasmic-reticulum; t-cell; antigen; beta-2-microglobulin; protein; line
AB MAJOR histocompatibility complex: class I molecules bind antigenic peptides in the endoplasmic reticulum (ER) and transport them to the cell surface for recognition by cytotoxic T lymphocytes. The peptides are predominantly generated from cytoplasmic proteins, probably by the action of the multicatalytic proteinase complex, or proteasome(1,2). They are transported into the ER by the transporters associated with antigen processing (TAP), a complex formed from two subunits, TAP.1 and TAP.2 (refs 3-5). Here we show that the TAP molecules are intimately involved in the assembly of the class I/beta(2)-microglobulin (beta(2)m) peptide complex. Free class I heavy chains are associated in the ER with the chaperone calnexin(6,7). In human B-cell lines, however, class I/beta(2)m dimers in the ER are physically associated with TAP molecules rather than calnexin. Our results suggest that calnexin mediates class I/beta(2)m dimerization, and subsequent binding of the dimers to TAP molecules facilitates their association with TAP-transported peptides.
RP ORTMANN, B (corresponding author), YALE UNIV,SCH MED,HOWARD HUGHES MED INST,IMMUNOBIOL SECT,310 CEDAR ST,NEW HAVEN,CT 06520, USA.
NR 28
TC 356
Z9 397
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 864
EP 867
DI 10.1038/368864a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700074
PM 8159247
DA 2026-03-10
ER

PT J
AU KATO, K
   CLARK, GD
   BAZAN, NG
   ZORUMSKI, CF
AF KATO, K
   CLARK, GD
   BAZAN, NG
   ZORUMSKI, CF
TI PLATELET-ACTIVATING-FACTOR AS A POTENTIAL RETROGRADE MESSENGER IN CA1 HIPPOCAMPAL LONG-TERM POTENTIATION
SO NATURE
LA English
DT Article
ID nitric-oxide; arachidonic-acid; dentate gyrus; rat; receptor; inhibition; currents; release; neurons; brain
AB LONG-term potentiation (LTP) refers to a persisting enhancement of neurotransmission that follows high-frequency activation of certain synapses1. Although both pre- and postsynaptic mechanisms contribute to LTP2,3, it is believed that the enhanced release of neurotransmitter that accompanies this process results from the production of a diffusible messenger in postsynaptic neurons which traverses the synaptic cleft and alters the function of presynaptic terminals4,5. One candidate for such a messenger is arachidonic acid, a metabolite produced by phospholipase A2 which augments synaptic transmission when coupled with presynaptic stimulations. However, the effects of arachidonic acid require activation of the postsynaptic receptor for N-methyl-D-aspartate6. Previously we found that platelet-activating factor (1 O-alkyl-2-acetyl-sn-glycero-3-phosphocholine), another phospholipase A2-derived messenger7, selectively enhances excitatory postsynaptic currents in hippocampal neurons by a presynaptic mechanism8. We now present evidence that platelet-activating factor, acting at a receptor localized to synaptic regions, participates in LTP in the CA1 region of rat hippocampal slices and may serve as part of a retrograde signalling cascade.
C1 WASHINGTON UNIV, SCH MED, DEPT PSYCHIAT, 4940 CHILDRENS PL, ST LOUIS, MO 63110 USA.
   WASHINGTON UNIV, SCH MED, DEPT NEUROBIOL, ST LOUIS, MO 63110 USA.
   LOUISIANA STATE UNIV, MED CTR, SCH MED, CTR NEUROSCI, NEW ORLEANS, LA 70112 USA.
   LOUISIANA STATE UNIV, MED CTR, SCH MED, DEPT NEUROL, NEW ORLEANS, LA 70112 USA.
   LOUISIANA STATE UNIV, MED CTR, SCH MED, DEPT OPHTHALMOL, NEW ORLEANS, LA 70112 USA.
C3 Washington University (WUSTL); Washington University (WUSTL); Louisiana State University System; Louisiana State University System; Louisiana State University System
NR 30
TC 228
Z9 246
U1 0
U2 7
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 175
EP 179
DI 10.1038/367175a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000062
PM 8114914
DA 2026-03-10
ER

PT J
AU ZORIO, DAR
   CHENG, NSN
   BLUMENTHAL, T
   SPIETH, J
AF ZORIO, DAR
   CHENG, NSN
   BLUMENTHAL, T
   SPIETH, J
TI OPERONS AS A COMMON FORM OF CHROMOSOMAL ORGANIZATION IN C-ELEGANS
SO NATURE
LA English
DT Article
ID nematode caenorhabditis-elegans; leader sequence; messenger-rna; gene; protein
AB ALTHOUGH eukaryotic genes are usually transcribed individually, at least a few Caenorhabditis elegans genes appear to be transcribed polycistronically in clusters resembling bacterial operons(1). The spliced leader SL2 (ref. 2) is specific for trans-splicing to downstream genes in these operons(1). In addition, many C. elegans pre-mRNAs are trans-spliced to SL1 (ref. 3) near the 5' ends of pre-mRNAs(4,5). Because operons have not previously been found in higher eukaryotes, we have investigated how widespread they are in the C. elegans genome. We identified gene clusters using the extensive data generated by the genome project(6,7) and tested seven for trans-splicing specificity. All were found to fit expectations for polycistronic transcription. In addition, we surveyed reported C. elegans genes for irans-splicing specificity. Both methods indicate that the pre-mRNAs of about 70% of C. elegans genes are trans-spliced and as many as a quarter are transcribed in operons.
RP ZORIO, DAR (corresponding author), INDIANA UNIV, DEPT BIOL, BLOOMINGTON, IN 47405 USA.
NR 17
TC 228
Z9 251
U1 1
U2 12
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 270
EP 272
DI 10.1038/372270a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900052
PM 7969472
DA 2026-03-10
ER

PT J
AU ANGEL, JRP
AF ANGEL, JRP
TI GROUND-BASED IMAGING OF EXTRASOLAR PLANETS USING ADAPTIVE OPTICS
SO NATURE
LA English
DT Article
ID systems
AB The detection of extrasolar planets by direct imaging presents an extraordinary technical challenge. They must be identified against background light scattered from a star close by and about a billion times brighter. It has been supposed that a near-perfect space telescope would be required to avoid atmospheric blurring. But by using adaptive optics operating at fundamental performance limits, the new generation of large ground-based telescopes has the potential to detect planets orbiting nearby stars.
RP ANGEL, JRP (corresponding author), UNIV ARIZONA,STEWARD OBSERV,TUCSON,AZ 85721, USA.
NR 27
TC 186
Z9 196
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 203
EP 207
DI 10.1038/368203a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000044
DA 2026-03-10
ER

PT J
AU STARK, K
   VAINIO, S
   VASSILEVA, G
   MCMAHON, AP
AF STARK, K
   VAINIO, S
   VASSILEVA, G
   MCMAHON, AP
TI EPITHELIAL TRANSFORMATION OF METANEPHRIC MESENCHYME IN THE DEVELOPING KIDNEY REGULATED BY WNT-4
SO NATURE
LA English
DT Article
ID developing excretory system; wilms-tumor gene; mouse development; expression; protooncogene; embryo; disruption; homolog
AB THE kidney has been widely exploited as a model system for the study of tissue inductions regulating vertebrate organogenesis(1,2). Kidney development is initiated by the ingrowth of the Wolfian duct-derived ureteric bud into the presumptive kidney mesenchyme. In response to a signal from the ureter, mesenchymal cells condense, aggregate into pretubular clusters and undergo an epithelial conversion generating a simple tubule. This then undergoes morphogenesis and is transformed into the excretory system of the kidney, the nephron. We report here that the expression of Wnt-4, which encodes a secreted glycoprotein, correlates with, and is required for, kidney tubulogenesis. Mice lacking Wnt-1 activity fail to form pretubular cell aggregates; however, other aspects of mesenchymal and ureteric development are unaffected. Thus, Wnt-4 appears to act as an autoinducer of the mesenchyme to epithelial transition that underlies nephron development.
C1 HARVARD UNIV, DEPT MOLEC & CELLULAR BIOL, BIOLABS, CAMBRIDGE, MA 02138 USA.
C3 Harvard University
NR 30
TC 892
Z9 1027
U1 0
U2 17
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 679
EP 683
DI 10.1038/372679a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700087
PM 7990960
DA 2026-03-10
ER

PT J
AU KAWAKATSU, H
   NIU, FL
AF KAWAKATSU, H
   NIU, FL
TI SEISMIC EVIDENCE FOR A 920-KM DISCONTINUITY IN THE MANTLE
SO NATURE
LA English
DT Article
ID mgsio3 perovskite; western pacific; beneath; zone
AB Analysis of hundreds of seismograms from a seismic array in the Japanese islands reveals a seismic discontinuity at a depth of about 920 km in the mantle beneath the Tonga subduction zone. This discontinuity is also evident beneath subduction zones in the Japan and Flores seas. The discontinuity probably represents either a change in mantle chemical composition or the signature of the subducted slab's garnet layer.
RP KAWAKATSU, H (corresponding author), UNIV TOKYO,EARTHQUAKE RES INST,BUNKYO KU,1-1-1 YAYOI,TOKYO 113,JAPAN.
NR 41
TC 175
Z9 197
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 301
EP 305
DI 10.1038/371301a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400043
DA 2026-03-10
ER

PT J
AU WRANA, JL
   ATTISANO, L
   WIESER, R
   VENTURA, F
   MASSAGUE, J
AF WRANA, JL
   ATTISANO, L
   WIESER, R
   VENTURA, F
   MASSAGUE, J
TI MECHANISM OF ACTIVATION OF THE TGF-BETA RECEPTOR
SO NATURE
LA English
DT Article
ID transforming growth-factor; transmembrane serine kinase; expression cloning; activin receptor; ii receptors; signal transduction; cell-proliferation; threonine kinase; identification; inhibition
AB Transforming growth factor-beta (TGF-beta) signals by contacting two distantly related transmembrane serine/threonine kinases called receptors I and II. The role of these molecules in signalling has now been determined. TGF-beta binds directly to receptor II, which is a constitutively active kinase. Bound TGF-beta is then recognized by receptor I which is recruited into the complex and becomes phosphorylated by receptor II. Phosphorylation allows receptor I to propagate the signal to downstream substrates. This provides a mechanism by which a cytokine can generate the first step of a signalling cascade.
C1 MEM SLOAN KETTERING CANC CTR, HOWARD HUGHES MED INST, NEW YORK, NY 10021 USA.
   MEM SLOAN KETTERING CANC CTR, CELL BIOL & GENET PROGRAM, NEW YORK, NY 10021 USA.
C3 Memorial Sloan Kettering Cancer Center; Howard Hughes Medical Institute; Memorial Sloan Kettering Cancer Center
NR 43
TC 2148
Z9 2561
U1 0
U2 102
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 341
EP 347
DI 10.1038/370341a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400046
PM 8047140
DA 2026-03-10
ER

PT J
AU WANG, YT
   SALTER, MW
AF WANG, YT
   SALTER, MW
TI REGULATION OF NMDA RECEPTORS BY TYROSINE KINASES AND PHOSPHATASES
SO NATURE
LA English
DT Article
ID long-term potentiation; excitatory amino-acids; phosphorylation; activation; inhibitor; neurons; cells
AB PROTEIN-TYROSINE kinases (PTKs) and protein-tyrosine phosphatases (PTPs) are key enzymes in signal-transduction pathways for a wide range of cellular processes(1,2). PTKs and PTPs are highly expressed in the central nervous system(3), which is consistent with the importance of tyrosine phosphorylation in neuronal function(4-6). Protein phosphorylation is known to be involved in the regulation of neurotransmitter receptors(7,8), but the effects of tyrosine phosphorylation on neurotransmitter receptor function in the central nervous system are unknown. Here we present evidence that in mammalian central neurons tyrosine phosphorylation regulates the function of the NMDA (N-methyl-D-aspartate) receptor, a subtype of excitatory amino-acid receptor(9,10). NMDA-receptor-mediated whole-cell currents and intracellular Ca2+ responses are depressed by inhibition of PTKs. Conversely, NMDA currents are potentiated by intracellular application of the well characterized PTK pp60(c-src). NMDA currents are also potentiated by intracellular administration of an inhibitor of PTPs. Protein-tyrosine phosphorylation is a new mechanism for regulating NMDA receptors and may be important in neuronal development, plasticity and toxicity.
C1 HOSP SICK CHILDREN,DIV NEUROSCI,TORONTO M5G 1X8,ON,CANADA.
   UNIV TORONTO,DEPT PHYSIOL,TORONTO M5S 1A8,ON,CANADA.
C3 University of Toronto; Hospital for Sick Children (SickKids); University of Toronto
NR 24
TC 642
Z9 719
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 233
EP 235
DI 10.1038/369233a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700056
PM 7514272
DA 2026-03-10
ER

PT J
AU NOTZEL, R
   TEMMYO, J
   TAMAMURA, T
AF NOTZEL, R
   TEMMYO, J
   TAMAMURA, T
TI SELF-ORGANIZED GROWTH OF STRAINED INGAAS QUANTUM DISKS
SO NATURE
LA English
DT Article
ID surfaces; wires; well
AB LATERAL confinement of electrons or excitons in low-dimensional semiconductor structures (quantum 'wires' and 'boxes') leads to new electronic properties(1), which can be used to improve the performance of optical devices such as semiconductor lasers and nonlinear optical switches(2-4). Several state-of-the-art technologies have been applied to fabricate these quantum structures: lateral structure can be defined using high-resolution lithography combined with dry etching(5,6), or by crystal growth on masked substrates(7,8). Unfortunately, such processes inevitably result in a deterioration of the crystal quality. But recent reports(9,10) of self-organized formation of quantum-wire semiconductor structures have attracted considerable interest as a means of overcoming these difficulties. We describe here the self-organized formation of box-like microstructures during the interrupted epitaxial growth of strained InGaAs/AlGaAs multilayer structures on (311)B gallium arsenide substrates. We find that the InGaAs layers organize spontaneously into homogeneous nanoscale disks embedded in an AlGaAs matrix. This phenomenon appears to arise from a complex interplay between the lattice strain, surface energy and surface migration.
RP NOTZEL, R (corresponding author), NTT OPTOELECTR LABS,3-1 MORINOSATO WAKAMIYA,ATSUGI,KANAGAWA 24301,JAPAN.
NR 17
TC 352
Z9 359
U1 0
U2 37
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 131
EP 133
DI 10.1038/369131a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100043
DA 2026-03-10
ER

PT J
AU BAUMBERGER, T
   HESLOT, F
   PERRIN, B
AF BAUMBERGER, T
   HESLOT, F
   PERRIN, B
TI CROSSOVER FROM CREEP TO INERTIAL MOTION IN FRICTION DYNAMICS
SO NATURE
LA English
DT Article
AB FRICTION between dry surfaces plays a role in solid dynamics over a wide range of length scales, from the mechanics of micromachines to earthquakes. Some common features of frictional dynamics have been observed for rather different materials, such as rock sliding on rock or metal on metal1,2. But there is still relatively little understanding of the way in which frictional motion varies generically with mechanical parameters. Here we present the results of experiments on frictional sliding of Bristol board, which show how the characteristics of frictional sliding depend on mass, driving velocity and stiffness of the driving spring constant. In general, there is a bifurcation from stick-slip to steady sliding with increasing velocity. The character of the frictional motion and of the associated bifurcation changes with velocity: at low speeds creep is dominant, which can be ascribed a characteristic length, whereas at high speeds the motion can be described as inertial, with a characteristic timescale. The kinetic friction coefficient decreases with increasing velocity in the former case, and increases with velocity in the latter. We anticipate that these results are likely to be generic.
C1 UNIV PARIS 06,PHYS MAT CONDENSEE LAB,F-75230 PARIS 05,FRANCE.
   UNIV PARIS 07,PHYS MAT CONDENSEE LAB,F-75221 PARIS 05,FRANCE.
C3 Sorbonne Universite; Universite Paris Cite
RP BAUMBERGER, T (corresponding author), ECOLE NORMALE SUPER,CNRS,PHYS MAT CONDENSEE LAB,24 RUE LHOMOND,F-75231 PARIS 05,FRANCE.
NR 13
TC 157
Z9 172
U1 2
U2 44
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 544
EP 546
DI 10.1038/367544a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300053
DA 2026-03-10
ER

PT J
AU FUMAGALLI, S
   TOTTY, NF
   HSUAN, JJ
   COURTNEIDGE, SA
AF FUMAGALLI, S
   TOTTY, NF
   HSUAN, JJ
   COURTNEIDGE, SA
TI A TARGET FOR SRC IN MITOSIS
SO NATURE
LA English
DT Article
ID tyrosine kinases; growth-factor; signal transduction; c-src; protein; phosphorylation; activation; gap; identification; association
AB THE activity of the c-Src protein is increased during cell-cycle stage G1 in fibroblasts stimulated with certain growth factors(1-4), and at the G2/M transition(5), but little is known about Src substrates in these circumstances. In contrast, cells transformed with activated Src contain many tyrosine-phosphorylated proteins. We compared the phosphotyrosine content of growing and mitotically arrested Src-transformed cells. We report here that although phosphorylation of most proteins was unchanged during mitosis, phosphorylation of one of about 68K was greatly enhanced. The p68. was physically associated with activated c-Src, and it bound to the SH3 domain of c-Src in vitro. Tyrosine-phosphorylated p68 was also present in mitotic extracts of normal cells, suggesting that its phosphorylation was not just a consequence of transformation; Purification and microsequencing of p68 showed that it was related to the previously described GAP-associated protein p62 (ref. 6).
C1 EUROPEAN MOLEC BIOL LAB,D-69012 HEIDELBERG,GERMANY.
   LUDWIG INST CANC RES,MIDDLESEX BRANCH,LONDON W1P 8BT,ENGLAND.
C3 European Molecular Biology Laboratory (EMBL); Ludwig Institute for Cancer Research
NR 24
TC 343
Z9 383
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 871
EP 874
DI 10.1038/368871a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700076
PM 7512695
DA 2026-03-10
ER

PT J
AU BURNS, K
   DUGGAN, B
   ATKINSON, EA
   FAMULSKI, KS
   NEMER, M
   BLEACKLEY, RC
   MICHALAK, M
AF BURNS, K
   DUGGAN, B
   ATKINSON, EA
   FAMULSKI, KS
   NEMER, M
   BLEACKLEY, RC
   MICHALAK, M
TI MODULATION OF GENE-EXPRESSION BY CALRETICULIN BINDING TO THE GLUCOCORTICOID RECEPTOR
SO NATURE
LA English
DT Article
ID messenger-rna; protein; cells; dna
AB CALRETICULIN is a multifunctional protein that acts as a major Ca2+-binding (storage) protein in the lumen of the endoplasmic reticulum1. It is also found in the nucleus2, suggesting that it may have a role in transcription regulation. Calreticulin has been reported to bind to the synthetic peptide KLGFFKR3, which is almost identical to an amino-acid sequence in the DNA-binding domain of the superfamily of nuclear receptors4-6. Could calreticulin interact with the DNA-binding domain of these receptors and affect their function? Here we report that the amino terminus of calreticulin interacts with the DNA-binding domain of the glucocorticoid receptor and prevents the receptor from binding to its specific glucocorticoid response element. Overexpression of calreticulin in mouse L fibroblasts inhibits glucocorticoid-response-mediated transcriptional activation of a glucocorticoid-sensitive reporter gene and of the endogenous, glucocorticoid-sensitive gene encoding cytochrome P450. Together these results indicate that calreticulin may be important in gene transcription, regulating the glucocorticoid receptor and perhaps other members of the superfamily of nuclear receptors.
C1 UNIV ALBERTA, CARDIOVASC DIS RES GRP, EDMONTON T6G 2S2, AB, CANADA.
   UNIV ALBERTA, DEPT BIOCHEM, EDMONTON T6G 2S2, AB, CANADA.
   CLIN RES INST MONTREAL, MONTREAL H2W 1R7, QUEBEC, CANADA.
C3 University of Alberta; University of Alberta; Institut de Recherche Clinique de Montreal (IRCM); Universite de Montreal
NR 19
TC 351
Z9 386
U1 0
U2 6
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 476
EP 480
DI 10.1038/367476a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900059
PM 8107808
DA 2026-03-10
ER

PT J
AU HEBBELN, D
   DOKKEN, T
   ANDERSEN, ES
   HALD, M
   ELVERHOI, A
AF HEBBELN, D
   DOKKEN, T
   ANDERSEN, ES
   HALD, M
   ELVERHOI, A
TI MOISTURE SUPPLY FOR NORTHERN ICE-SHEET GROWTH DURING THE LAST-GLACIAL-MAXIMUM
SO NATURE
LA English
DT Article
ID norwegian sea; marine; deglaciation; spitsbergen; atlantic; history; ages
AB During the last ice age, the Barents Sea ice sheet began to grow 22 kyr ago(1), only 8 kyr before it began to disintegrate(2). This implies that the ice must have grown very rapidly from the coast to the edge of the continental shelf. Such rapid growth of a large ice sheet requires significant amounts of moisture; but the origin of this moisture has been unclear, particularly as the CLIMAP climate reconstruction suggests(4,5) that the Greenland-Iceland-Norwegian (GIN) seas were perennially ice-covered during this period. Here we present data from deep-sea sediment cores from the Fram Strait, which suggest that relatively warm water from the North Atlantic Ocean was advected into the GIN seas in two short-term events (27-22.5 and 19.5-14.5 kyr ago). We suggest that the resulting seasonally ice-free waters were an important regional moisture source for the Barents Sea ice sheet, and that the GIN seas played a much more active role in climate during the last glaciation than has previously been supposed.
C1 UNIV TROMSO, INST BIOL & GEOL, N-9037 TROMSO, NORWAY.
   UNIV OSLO, INST GEOL, N-0316 OSLO 3, NORWAY.
C3 UiT The Arctic University of Tromso; University of Oslo
RP HEBBELN, D (corresponding author), UNIV BREMEN, FACHBEREICH GEOWISSENSCH, POSTFACH 330440, D-28334 BREMEN, GERMANY.
NR 37
TC 212
Z9 220
U1 0
U2 17
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 357
EP 360
DI 10.1038/370357a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400051
DA 2026-03-10
ER

PT J
AU WANG, ZG
   SVEJSTRUP, JQ
   FEAVER, WJ
   WU, XH
   KORNBERG, RD
   FRIEDBERG, EC
AF WANG, ZG
   SVEJSTRUP, JQ
   FEAVER, WJ
   WU, XH
   KORNBERG, RD
   FRIEDBERG, EC
TI TRANSCRIPTION FACTOR-B (TFIIH) IS REQUIRED DURING NUCLEOTIDE-EXCISION REPAIR IN YEAST
SO NATURE
LA English
DT Article
ID human cell-extracts; dna-repair; saccharomyces-cerevisiae; xeroderma-pigmentosum; gene; mutagenesis; polymerase; helicase; homolog; cloning
AB NUCLEOTIDE-excision repair (NER)(1) is an important cellular defence mechanism against mutagenesis and carcinogenesis. The essential yeast genes RAD3 (ref 2) and SSL2 (RAD25)(3,4), homologues of the human xeroderma pigmentosum genes XPD(5,6) and XPB(7) respectively, have been implicated in NER in yeast. The products of these genes are also subunits of (Rad3 protein) or associate with (Ssl2 protein) purified yeast RNA polymerase II transcription initiation factor b, the counterpart of human TFIIH8. Rad3 and Ssl2 proteins may participate directly in NER. Alternatively, they may function exclusively as transcription factors that support NER by influencing the expression of other NER genes. Here we show that defective NER in rad3 mutant extracts can be specifically complemented by purified transcription factor b. Similarly, defective NER in ssl2 mutant extracts is corrected by purified factor b/Ssl2 complex. These results support a direct role of factor b during NER in yeast. Hence, factor b (TFlIH) has a dual role in transcription and NER.
C1 STANFORD UNIV,SCH MED,DEPT CELL BIOL,STANFORD,CA 94305.
C3 Stanford University
RP WANG, ZG (corresponding author), UNIV TEXAS,SW MED CTR,DEPT PATHOL,MOLEC PATHOL LAB,DALLAS,TX 75235, USA.
NR 27
TC 157
Z9 162
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 74
EP 76
DI 10.1038/368074a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900057
PM 8107888
DA 2026-03-10
ER

PT J
AU SWADDLE, JP
   CUTHILL, IC
AF SWADDLE, JP
   CUTHILL, IC
TI PREFERENCE FOR SYMMETRICAL MALES BY FEMALE ZEBRA FINCHES
SO NATURE
LA English
DT Article
ID sex-ratio manipulation; fluctuating asymmetry; color preferences; band-color; ornaments; selection; patterns; populations; evolution; quality
AB FLUCTUATING asymmetries are the small random deviations from symmetry that occur in the development of bilaterally symmetrical traits1. Such asymmetries are believed to be a direct indicator of phenotypic, perhaps genotypic, quality2. Relative levels of asymmetry are much greater in secondary sexual characters than in normal morphological traits2.  It has been proposed that females use the amount of asymmetry in secondary sexual ornamentation as a cue in mate choice3, because the highest quality individuals have the most symmetrical, as well as elaborate, ornaments2-10. Using a choice chamber similar to that in ref. 11, we show here that female zebra finches choose symmetrically leg-banded males over asymmetrically banded ones. This demonstrates unequivocally that females use symmetry as a criterion in partner preference, although whether the symmetry preference is specific to secondary sexual characters is unknown.
RP SWADDLE, JP (corresponding author), UNIV BRISTOL,SCH BIOL SCI,WOODLAND RD,BRISTOL BS8 1UG,AVON,ENGLAND.
NR 29
TC 191
Z9 200
U1 1
U2 35
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 165
EP 166
DI 10.1038/367165a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000058
DA 2026-03-10
ER

PT J
AU ARTALEJO, CR
   ADAMS, ME
   FOX, AP
AF ARTALEJO, CR
   ADAMS, ME
   FOX, AP
TI 3 TYPES OF CA2+ CHANNEL TRIGGER SECRETION WITH DIFFERENT EFFICACIES IN CHROMAFFIN CELLS
SO NATURE
LA English
DT Article
ID calcium channels; capacitance measurements; omega-conotoxin; facilitation
AB To determine whether the different types of Ca2+ channels present in the same secretory cell contribute equally to secretion, we used chromaffin cells to analyse the coupling between three distinct types of Ca2+ channel1 and exocytosis2,3.  These are omega-conotoxin-GVIA-sensitive4,5 N-type channels, omega-agatoxin-IVA-sensitive P-type Ca2+ channels6 and dihydropyridine-sensitive facilitation Ca2+ channels, which are normally quiescent but are activated by depolarizing pre-pulses, repetitive depolarizations to physiological potentials7,8, or agents that raise cyclic AMP9. We have simultaneously monitored changes in capacitance as an assay of catecholamine secretion10, and Ca2+ currents. Although all three types of Ca2+ channel trigger secretion individually, facilitation channels produce much greater secretion for a given size of Ca2+ current, indicating that they are coupled more efficiently to exocytosis. These results indicate that facilitation Ca2+ channels may be physically nearer vesicle release sites. They also show that low efficiency P- and N-type channels could trigger mild release and that high-efficiency facilitation channels may underlie the massive catecholamine release that occurs during the 'fight or flight' response.
C1 UNIV AUTONOMA MADRID,FAC MED,DEPT FARMACOL,E-28029 MADRID,SPAIN.
   UNIV CALIF RIVERSIDE,DEPT ENTOMOL & NEUROSCI,RIVERSIDE,CA 92521.
   UNIV CHICAGO,DEPT PHARMACOL & PHYSIOL SCI,CHICAGO,IL 60637.
C3 Autonomous University of Madrid; University of California System; University of California Riverside; University of Chicago
RP ARTALEJO, CR (corresponding author), NORTHWESTERN UNIV,DEPT NEUROBIOL & PHYSIOL,2153 N CAMPUS DR,EVANSTON,IL 60208, USA.
NR 22
TC 254
Z9 263
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 72
EP 76
DI 10.1038/367072a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500062
PM 8107778
DA 2026-03-10
ER

PT J
AU MULKEY, RM
   ENDO, S
   SHENOLIKAR, S
   MALENKA, RC
AF MULKEY, RM
   ENDO, S
   SHENOLIKAR, S
   MALENKA, RC
TI INVOLVEMENT OF A CALCINEURIN/INHIBITOR-1 PHOSPHATASE CASCADE IN HIPPOCAMPAL LONG-TERM DEPRESSION
SO NATURE
LA English
DT Article
ID protein phosphatases; area ca1; phosphorylation; identification; memory
AB LONG-TERM potentiation (LTP) is a synaptic mechanism thought to be involved in learning and memory(1). Long-term depression (LTD), an activity-dependent decrease in synaptic efficacy, may be an equally important mechanism which permits neural networks to store information more effectively(2,3). One form of LTD that has been observed in the hippocampus(4) requires activation of postsynaptic NMDA (N-methyl-D-aspartate) receptors(4,5), a change in postsynaptic calcium concentration(5), and activation of postsynaptic serine/threonine protein phosphatase 1 (PP1) or 2A (PP2A)(6). The mechanism by which PP1 or PP2A is regulated by synaptic activity is unclear because these protein phosphatases are not directly influenced by calcium concentration. LTD induction may require activation of a more complex protein phosphatase cascade consisting of the Ca2+/calmodulin-dependent protein phosphatase, calcineurin, its phosphoprotein substrate, inhibitor-1, and PP1(7,8). We tested this hypothesis using calcineurin inhibitors as well as different forms of inhibitor-1 loaded into postsynaptic cells. Our results suggest a signalling pathway in which calcineurin dephosphorylates and inactivates inhibitor-1. This in turn increases PP1 activity and contributes to the generation of LTD.
C1 UNIV CALIF SAN FRANCISCO, DEPT PSYCHIAT, SAN FRANCISCO, CA 94143 USA.
   UNIV CALIF SAN FRANCISCO, DEPT PHYSIOL, SAN FRANCISCO, CA 94143 USA.
   DUKE UNIV, MED CTR, DEPT PHARMACOL, DURHAM, NC 27710 USA.
C3 University of California System; University of California San Francisco; University of California System; University of California San Francisco; Duke University
NR 17
TC 920
Z9 1087
U1 1
U2 26
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 486
EP 488
DI 10.1038/369486a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600057
PM 7515479
DA 2026-03-10
ER

PT J
AU GEPPERT, M
   BOLSHAKOV, VY
   SIEGELBAUM, SA
   TAKEI, K
   DECAMILLI, P
   HAMMER, RE
   SUDHOF, TC
AF GEPPERT, M
   BOLSHAKOV, VY
   SIEGELBAUM, SA
   TAKEI, K
   DECAMILLI, P
   HAMMER, RE
   SUDHOF, TC
TI THE ROLE OF RAB3A IN NEUROTRANSMITTER RELEASE
SO NATURE
LA English
DT Article
ID gtp-binding protein; synaptic vesicles; transmitter release; synapsin-i; probability; exocytosis; plasticity; receptor; neurons; mice
AB THE small GTP-binding protein Rab3A is a Rab family member(1-3) that is abundant in brain synaptic vesicles(4,5). Here we show that mice in which the rab3A gene has been mutated by homologous recombination do not express Rab3A but are viable and fertile. Electrophysiological recordings in hippocampal CA1 pyramidal cells indicate that most of their synaptic parameters are also normal, although synaptic depression after short trains of repetitive stimuli (15-30 stimuli at 14 Hz) is significantly increased. Levels of the Rab3A-binding protein rabphilin are decreased by 70%, but expression of more than 20 other synaptic proteins is unchanged. No compensatory changes were detected in other GTP-binding proteins or in proteins that interact with Rab3. Rab3A thus appears not to be essential for synaptic vesicle exocytosis but to play a role in the recruitment of synaptic vesicles for exocytosis during repetitive stimulation.
C1 UNIV TEXAS, SW MED CTR, DEPT MOLEC GENET, DALLAS, TX 75235 USA.
   UNIV TEXAS, SW MED CTR, DEPT BIOCHEM, DALLAS, TX 75235 USA.
   UNIV TEXAS, SW MED CTR, HOWARD HUGHES MED INST, DALLAS, TX 75235 USA.
   COLUMBIA UNIV, HOWARD HUGHES MED INST, CTR NEUROBIOL & BEHAV, DEPT PHARMACOL, NEW YORK, NY 10032 USA.
   YALE UNIV, SCH MED, DEPT CELL BIOL, NEW HAVEN, CT 06510 USA.
   YALE UNIV, SCH MED, HOWARD HUGHES MED INST, NEW HAVEN, CT 06510 USA.
C3 University of Texas System; University of Texas Dallas; University of Texas Southwestern Medical Center; University of Texas System; University of Texas Southwestern Medical Center; University of Texas Dallas; University of Texas System; University of Texas Southwestern Medical Center; Howard Hughes Medical Institute; University of Texas Dallas; Howard Hughes Medical Institute; Columbia University; Yale University; Howard Hughes Medical Institute; Yale University
NR 30
TC 430
Z9 483
U1 0
U2 16
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 493
EP 497
DI 10.1038/369493a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600060
PM 7911226
DA 2026-03-10
ER

PT J
AU GUBBINS, D
   SARSON, G
AF GUBBINS, D
   SARSON, G
TI GEOMAGNETIC-FIELD MORPHOLOGIES FROM A KINEMATIC DYNAMO MODEL
SO NATURE
LA English
DT Article
ID reversal; symmetry; dipole
AB THE Earth's magnetic field is generated by flow of liquid iron in the outer core, acting as a dynamo. In the simple kinematic theory a fluid flow is prescribed and tested for its ability to generate magnetic field, no account being taken of the forces required to drive the flow. Although incomplete, kinematic theory gives valuable insight into the more difficult dynamical problem and produces field morphologies which can be compared with observations. We are attempting a comprehensive study of three-dimensional kinematic dynamo action for a class of fluid flow typical of that driven by convection (G.S. and D.G., manuscript in preparation), and have already found similarities between steady dipole solutions and the geomagnetic field(1). Here we examine the effect of meridian circulation in determining the stability of steady and oscillatory solutions. The magnetic field morphology on both sides of the stability boundary is determined by magnetic flux concentration by downwelling fluid(2). The oscillatory dipole reverses polarity through the appearance and poleward migration of patches of reversed flux, similar to those seen in today's geomagnetic field(3). Virtual geomagnetic poles computed from the reversing field follow paths that are concentrated along the longitudes of maximum flux, suggesting a link with recent palaeomagnetic results(4-7).
RP GUBBINS, D (corresponding author), UNIV LEEDS, DEPT EARTH SCI, LEEDS LS2 9JT, W YORKSHIRE, ENGLAND.
NR 28
TC 30
Z9 30
U1 0
U2 1
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 51
EP 55
DI 10.1038/368051a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900049
DA 2026-03-10
ER

PT J
AU DIBROZOLO, FR
   BUNCH, TE
   FLEMING, RH
   MACKLIN, J
AF DIBROZOLO, FR
   BUNCH, TE
   FLEMING, RH
   MACKLIN, J
TI FULLERENES IN AN IMPACT CRATER ON THE LDEF SPACECRAFT
SO NATURE
LA English
DT Article
ID environment; c-60
AB THE fullerenes C-60 (ref. 1) and C-70 have been found to occur naturally on Earth(2,3), and have also been invoked to explain features in the absorption spectra of interstellar clouds(1,4). But no definitive spectroscopic evidence exists for fullerenes in space and attempts to find fullerenes in carbonaceous chondrites have been unsuccessful(5,6), Here we report the observation of fullerenes associated with carbonaceous impact residue in a crater on the Long Duration Exposure Facility (LDEF) spacecraft. Laser ionization mass spectrometry and Raman spectroscopy indicate the presence of fullerenes in the crater and in adjacent ejecta. Man-made fullerenes survive experimental hypervelocity (similar to 6.1 km s(-1)) impacts into aluminium targets, suggesting that space fullerenes contained in a carbonaceous micrometeorite could have survived the LDEF impact at velocities towards the lower end of the natural particle encounter range (<13 km s(-1)). We also demonstrate that the fullerenes were unlikely to have formed as instrumental artefacts, nor are they present as contaminants. Although we cannot specify the origin of the fullerenes with certainty, the most plausible source is the chondritic impactor. If, alternatively, the impact produced the fullerenes in situ on LDEF, then this suggests a viable mechanism for fullerene production in space.
C1 NASA, AMES RES CTR, PLANETARY BIOL BRANCH, MOFFETT FIELD, CA 94035 USA.
   UNIV WASHINGTON, DEPT CHEM, SEATTLE, WA 98195 USA.
C3 National Aeronautics & Space Administration (NASA); NASA Ames Research Center; University of Washington; University of Washington Seattle
RP DIBROZOLO, FR (corresponding author), CHARLES EVANS & ASSOCIATES, REDWOOD CITY, CA 94063 USA.
NR 17
TC 40
Z9 41
U1 0
U2 8
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 37
EP 40
DI 10.1038/369037a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000044
PM 11541208
DA 2026-03-10
ER

PT J
AU KAMIYA, H
   ZUCKER, RS
AF KAMIYA, H
   ZUCKER, RS
TI RESIDUAL CA2+ AND SHORT-TERM SYNAPTIC PLASTICITY
SO NATURE
LA English
DT Article
ID frog neuromuscular-junction; squid giant synapse; transmitter release; posttetanic potentiation; calcium chelators; intracellular calcium; nerve-terminals; dm-nitrophen; facilitation; ca-2+
AB AT many synapses, the amount of transmitter released by action potentials increases progressively during a train of spikes. This enhancement of evoked transmitter release grows during tetanic stimulation with several time constants, each bearing a different name (facilitation: tens to hundreds of milliseconds; augmentation: several seconds; potentiation: several minutes), and the enhancement of release to test spikes after a tetanus decays with similar time constants. All these processes depend on presynaptic Ca2+ influx during the conditioning tetanus(1). It has often been proposed that these forms of synaptic plasticity are due to residual Ca2+ present in nerve terminals following conditioning activity(2). We tested this idea directly by using photolabile Ca2+ chelators to reduce residual Ca2+ following conditioning stimulation or to generate an artificial elevation in Ca2+ concentration, and observed the effects on synaptic transmission at crayfish neuromuscular junctions. We found that facilitation, augmentation and potentiation are caused by the continuing action of residual Ca2+. Augmentation and potentiation seem to arise from Ca2+ acting at a separate site from facilitation, and these sites are different from the molecular target triggering neurosecretion.
C1 UNIV CALIF BERKELEY, DIV NEUROBIOL, BERKELEY, CA 94720 USA.
C3 University of California System; University of California Berkeley
NR 30
TC 295
Z9 327
U1 0
U2 13
PU NATURE RESEARCH
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 603
EP 606
DI 10.1038/371603a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900051
PM 7935792
DA 2026-03-10
ER

PT J
AU THOMPSON, JS
   LING, XF
   GRUNSTEIN, M
AF THOMPSON, JS
   LING, XF
   GRUNSTEIN, M
TI HISTONE H3 AMINO-TERMINUS IS REQUIRED FOR TELOMERIC AND SILENT MATING LOCUS REPRESSION IN YEAST
SO NATURE
LA English
DT Article
ID saccharomyces-cerevisiae; transcriptional states; n-terminus; invivo
AB HETEROCHROMATIN is a cytologically visible form of condensed chromatin capable of repressing genes in eukaryotic cells. For the yeast Saccharomyces cerevisiae, despite the absence of observable heterochromatin, there is genetic and chromatin structure data which indicate that there are heterochromatin-like repressive structures(1-2). Genes experience position effects at the silent mating loci and the telomeres, resulting in a repressed state that is inherited in an epigenetic manner. The histone H4 amino terminus is required for repression at these loci(3,4). Additional studies have indicated that the histone H3 N terminus is not important for silent mating locus repression(5,6), but redundancy of repressive elements at the silent mating loci may be responsible for masking its role. Here we report that histone H3 is required for full repression at yeast telomeres and at partially disabled silent mating loci, and that the acetylatable lysine residues of H3 play an important role in silencing.
C1 UNIV CALIF LOS ANGELES, DEPT BIOL, LOS ANGELES, CA 90024 USA.
C3 University of California System; University of California Los Angeles
RP THOMPSON, JS (corresponding author), UNIV CALIF LOS ANGELES, INST MOLEC BIOL, LOS ANGELES, CA 90024 USA.
NR 18
TC 214
Z9 246
U1 0
U2 4
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 245
EP 247
DI 10.1038/369245a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700060
PM 8183346
DA 2026-03-10
ER

PT J
AU BERTINA, RM
   KOELEMAN, BPC
   KOSTER, T
   ROSENDAAL, FR
   DIRVEN, RJ
   DERONDE, H
   VANDERVELDEN, PA
   REITSMA, PH
AF BERTINA, RM
   KOELEMAN, BPC
   KOSTER, T
   ROSENDAAL, FR
   DIRVEN, RJ
   DERONDE, H
   VANDERVELDEN, PA
   REITSMA, PH
TI MUTATION IN BLOOD-COAGULATION FACTOR-V ASSOCIATED WITH RESISTANCE TO ACTIVATED PROTEIN-C
SO NATURE
LA English
DT Article
ID factor-xa; complete cdna; factor-viii; ceruloplasmin; deficiency; inhibition; sequence; thrombin; cloning; heparin
AB ACTIVATED protein C (APC) is a serine protease with potent anticoagulant properties, which is formed in blood on the endothelium from an inactive precursor(1). During normal haemostasis, APC limits clot formation by proteolytic inactivation of factors Va and VIIIa (ref. 2). To do this efficiently the enzyme needs a nonenzymatic cofactor, protein S (ref. 3). Recently it was found that the anticoagulant response to APC (APC resistance)(4) was very weak in the plasma of 21% of unselected consecutive patients with thrombosis(5) and about 50% of selected patients with a personal or family history of thrombosis(6,7); moreover, 5% of healthy individuals show APC resistance, which is associated with a sevenfold increase in the risk for deep vein thrombosis(5). Here we demonstrate that the phenotype of APC resistance is associated with heterozygosity or homozygosity for a single point mutation in the factor V gene (at nucleotide position 1,691, G --> A substitution) which predicts the synthesis of a factor V molecule (FV Q506, or FV Leiden) that is not properly inactivated by APC. The allelic frequency of the mutation in the Dutch population is similar to 2% and is at least tenfold higher than that of all other known genetic risk factors for thrombosis (protein C (ref. 8), protein S (ref. 9), antithrombin(10) deficiency) together.
C1 UNIV LEIDEN HOSP,DEPT CLIN EPIDEMIOL,2300 RC LEIDEN,NETHERLANDS.
C3 Leiden University; Leiden University Medical Center (LUMC)
RP BERTINA, RM (corresponding author), UNIV LEIDEN HOSP,CTR HEMOSTASIS & THROMBOSIS RES,BLDG 1-C2R,POB 9600,2300 RC LEIDEN,NETHERLANDS.
NR 30
TC 3698
Z9 3933
U1 2
U2 158
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 64
EP 67
DI 10.1038/369064a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000054
PM 8164741
DA 2026-03-10
ER

PT J
AU MADDOX, J
   GEE, H
AF MADDOX, J
   GEE, H
TI MEXICO BID TO JOIN THE WORLD
SO NATURE
LA English
DT Article
NR 2
TC 3
Z9 4
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 789
EP 792
DI 
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700024
DA 2026-03-10
ER

PT J
AU FUJITA, M
   IBUKURO, F
   HAGIHARA, H
   OGURA, K
AF FUJITA, M
   IBUKURO, F
   HAGIHARA, H
   OGURA, K
TI QUANTITATIVE SELF-ASSEMBLY OF A [2]CATENANE FROM 2 PREFORMED MOLECULAR RINGS
SO NATURE
LA English
DT Article
ID cyclodextrins; complex; order
AB MOLECULES composed of interlocking rings are termed catenanes. Since the first synthesis of a two-ring catenane (a [2]catenane) in 1960(1), these and related interlinked compounds have attracted considerable interest2-10, in part from the perspective of forming molecular devices and nanoscale architectures11,12. Here we report the formation of a [2]catenane from two complete rings, reminiscent of the trick of interlinking 'magic rings'. This supermolecule, 1 in Fig. 1, exists in rapid equilibrium with the monomeric rings 2, as revealed by H-1 NMR and electrospray mass spectrometry. At low concentration of molecule 2, the equilibrium lies towards the monomers, but at higher concentrations the catenane is the overwhelmingly dominant species in solution.
RP FUJITA, M (corresponding author), CHIBA UNIV,FAC ENGN,DEPT APPL CHEM,1-33 YAYOICHO,INAGE KU,CHIBA 263,JAPAN.
NR 15
TC 402
Z9 429
U1 1
U2 65
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 720
EP 723
DI 10.1038/367720a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100053
DA 2026-03-10
ER

PT J
AU COLLINS, EJ
   GARBOCZI, DN
   WILEY, DC
AF COLLINS, EJ
   GARBOCZI, DN
   WILEY, DC
TI 3-DIMENSIONAL STRUCTURE OF A PEPTIDE EXTENDING FROM ONE END OF A CLASS-I MHC BINDING-SITE
SO NATURE
LA English
DT Article
ID viral peptides; 3-dimensional structure; crystal-structures; antigen; complexes; molecules; hla-b27; h-2k(b); hla-a2
AB CLASS I major histocompatibility complex (MHC) molecules present peptides to CD8(+) T cells for immunological surveillance (reviewed in ref. 1). The structures of complexes of class I MHC molecules with octamer, nonamer and decamer peptides determined until now(2-8) show a common binding mode, with both peptide termini bound in conserved pockets at the ends of the peptide binding site. Length variations were accommodated by the peptide bulging(5,6) or zig-zagging(4) in the middle. Here we describe the structure of a decamer peptide which binds with the carboxy-terminal residue positioned outside the peptide binding site. Several protein side chains have rearranged to allow the peptide to exit. The structure suggests that even longer peptides could bind. The energetic effect of the altered mode of binding has been assessed by measuring the stability of the complex to thermal denaturation. Peptides bound in this novel manner are stable at physiological temperature, raising questions about their role in T-cell recognition and their production by proteolytic processing.
C1 HARVARD UNIV,HOWARD HUGHES MED INST,CAMBRIDGE,MA 02138.
   HARVARD UNIV,DEPT MOLEC & CELLULAR BIOL,CAMBRIDGE,MA 02138.
C3 Harvard University; Howard Hughes Medical Institute; Harvard University
NR 25
TC 205
Z9 225
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 626
EP 629
DI 10.1038/371626a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900058
PM 7935798
DA 2026-03-10
ER

PT J
AU GINGERICH, PD
   RAZA, SM
   ARIF, M
   ANWAR, M
   ZHOU, XY
AF GINGERICH, PD
   RAZA, SM
   ARIF, M
   ANWAR, M
   ZHOU, XY
TI NEW WHALE FROM THE EOCENE OF PAKISTAN AND THE ORIGIN OF CETACEAN SWIMMING
SO NATURE
LA English
DT Article
AB MODERN whales (order Cetacea) are marine mammals that evolved from a land-mammal ancestor, probably a cursorial Palaeocene-Eocene mesonychid(1-3). Living whales are streamlined, lack external hind limbs, and all swim by dorsoventral oscillation of a heavily muscled tail(4,5). A steamlined rigid body minimizes resistance, while thrust is provided by a lunate horizontal fluke attached to the tail at a narrow base or pedicle(6). We describe here a new 46-47-million-year-old archaeocete intermediate between land mammals and later whales. It has short cervical vertebrae, a reduced femur, and the flexible sacrum, robust tail and high neural spines on lumbars and caudals required for dorsoventral oscillation of a heavily muscled tail. This is the oldest fossil whale described from deep-neritic shelf deposits, and it shows that tail swimming evolved early in the history of cetaceans.
C1 GEOL SURVEY PAKISTAN,PALEONTOL & STRATIG BRANCH,ISLAMABAD,PAKISTAN.
RP GINGERICH, PD (corresponding author), UNIV MICHIGAN,MUSEUM PALEONTOL,ANN ARBOR,MI 48109, USA.
NR 23
TC 111
Z9 126
U1 0
U2 45
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 844
EP 847
DI 10.1038/368844a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700068
DA 2026-03-10
ER

PT J
AU CAVA, RJ
   TAKAGI, H
   ZANDBERGEN, HW
   KRAJEWSKI, JJ
   PECK, WF
   SIEGRIST, T
   BATLOGG, B
   VANDOVER, RB
   FELDER, RJ
   MIZUHASHI, K
   LEE, JO
   EISAKI, H
   UCHIDA, S
AF CAVA, RJ
   TAKAGI, H
   ZANDBERGEN, HW
   KRAJEWSKI, JJ
   PECK, WF
   SIEGRIST, T
   BATLOGG, B
   VANDOVER, RB
   FELDER, RJ
   MIZUHASHI, K
   LEE, JO
   EISAKI, H
   UCHIDA, S
TI SUPERCONDUCTIVITY IN THE QUATERNARY INTERMETALLIC COMPOUNDS LNNI2B2C
SO NATURE
LA English
DT Article
ID c-60
AB THE attainment of unprecedentedly high transition temperatures (T(c)s) in the copper oxide superconductors illustrates how working with more complex chemical systems allows greater opportunity to balance opposing forces within a single chemical compound, leading to a better optimization of physical properties. For many desired properties, materials with optimal chemical complexity have undoubtedly not yet been found. This appears to be the case for the intermetallic superconductors, whose study has languished in recent years, and which almost never show T(c)s above 15 K. These are almost all binary compounds with substitution-type additives, or, rarely, true ternary compounds such as LuRh4B4 (T(c) = 11.7 K; refs 1, 2). If, as some argue (refs 3, 4), materials such as A(x)C60 (ref. 5) and Ba0.6K0.4BiO3 (refs 6, 7) are conventional electron-phonon superconductors with T(c)s of approximately 30 K, then the absence of higher T(c)s in intermetallic compounds may mean only that more complex materials have not been sufficiently explored. We have recently found superconductivity at 23 K (a T(c) equal to that of the previous intermetallic record holder, Nb3Ge; ref. 9) in the quaternary intermetallic system yttrium-palladium-boron-carbon8, but we were unable to identify the superconducting phase. Here we report superconductivity at temperatures up to 16.6 K for the single-phase quaternary intermetallic compounds LnNi2B2C (where Ln stands for Y, Tm, Er, Ho or Lu).  The presence of the 3d transition metal nickel, and the layered crystal structure10 raise intriguing questions about the origin of the superconductivity, and the relatively high T(c)s of these and the Y-Pd-B-C superconductor suggest that there may yet be more surprises in store.
C1 UNIV TOKYO,DEPT APPL PHYS,TOKYO 113,JAPAN.
   DELFT UNIV TECHNOL,NATL CTR HIGH RESOLUT ELECTRON MICROSCOPY,2628 AL DELFT,NETHERLANDS.
C3 University of Tokyo; Delft University of Technology
RP CAVA, RJ (corresponding author), AT&T BELL LABS,600 MT AVE,MURRAY HILL,NJ 07974, USA.
NR 13
TC 866
Z9 913
U1 3
U2 141
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 252
EP 253
DI 10.1038/367252a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400048
DA 2026-03-10
ER

PT J
AU TRENTHAM, N
AF TRENTHAM, N
TI DWARF GALAXIES AS THE SOURCE OF X-RAY-EMITTING GAS IN CLUSTERS
SO NATURE
LA English
DT Article
ID luminosity functions; dark matter; coma cluster; condensation; einstein; origin; halos
AB RICH clusters of galaxies contain more hot gas by mass than stars(1 3) . This gas is not associated with individual galaxies, but instead is smoothly distributed, like the dark matter that is inferred to reside in the clusters. Identifying the origin of this gas will allow us to constrain theories of galaxy formation by Placing limits on the efficiency with which gas is converted into stars and on the fraction of the cluster mass that is comprised of normal baryonic matter. Here me suggest that this gas was originally condensed into dwarf galaxies, precursors to the low-surface-brightness dwarf spheroidal galaxies now observed. The condensed gas would have fuelled a burst of star formation, leading to supernova-driven winds(4) which could have expelled the gas back into the intracluster-medium. We show that this model can easily account for most of the present X-ray-emitting cluster gas.
RP TRENTHAM, N (corresponding author), UNIV HAWAII,INST ASTRON,2680 WOODLAWN DR,HONOLULU,HI 96822, USA.
NR 35
TC 29
Z9 30
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 157
EP 159
DI 10.1038/372157a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800048
DA 2026-03-10
ER

PT J
AU LEVISON, HF
   DUNCAN, MJ
   WETHERILL, GW
AF LEVISON, HF
   DUNCAN, MJ
   WETHERILL, GW
TI SECULAR RESONANCES AND COMETARY ORBITS IN THE BETA-PICTORIS SYSTEM
SO NATURE
LA English
DT Article
ID circumstellar disk; lines; iras
AB THE dusty disk around the star beta Pictoris is believed to contain a large number of comet-like bodies(1,2). Transient absorption events associated with beta Pictoris have been observed at many wavelengths(3-6) and attributed to cometary objects on eccentric orbits passing between the star and the Earth(7). One unexplained aspect of these events is the large asymmetry between red-shifted and blue-shifted features: similar to 90% of the events are red-shifted(6). We show here that such an asymmetry is a natural consequence of the influence on cometary orbits of secular resonances associated with some planetary systems. Results from numerical integrations of test particles in a model of our Solar System show that the nu(6) secular resonance excites objects initially on near-circular orbits to high eccentricities while aligning their perihelia. Depending on the location of a distant observer, this alignment can produce an asymmetry similar to that observed for beta Pictoris. Our results imply the presence of at least two planets (a prerequisite for the existence of secular resonances) around beta Pictoris.
C1 QUEENS UNIV,DEPT PHYS,KINGSTON K7L 3N6,ON,CANADA.
   CARNEGIE INST WASHINGTON,DEPT TERR MAGNETISM,WASHINGTON,DC 20015.
C3 Queens University - Canada; Carnegie Institution for Science
RP LEVISON, HF (corresponding author), SW RES INST,DEPT SPACE SCI,6220 CULEBRA RD,SAN ANTONIO,TX 78238, USA.
NR 19
TC 31
Z9 32
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 441
EP 444
DI 10.1038/372441a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200049
DA 2026-03-10
ER

PT J
AU CORNELIUSSEN, B
   HOLM, M
   WALTERSSON, Y
   ONIONS, J
   HALLBERG, B
   THORNELL, A
   GRUNDSTROM, T
AF CORNELIUSSEN, B
   HOLM, M
   WALTERSSON, Y
   ONIONS, J
   HALLBERG, B
   THORNELL, A
   GRUNDSTROM, T
TI CALCIUM/CALMODULIN INHIBITION OF BASIC-HELIX-LOOP-HELIX TRANSCRIPTION FACTOR DOMAINS
SO NATURE
LA English
DT Article
ID dependent protein-kinase; calmodulin-binding proteins; mouse retrovirus sl3-3; dna-binding; sequence; enhancer; myod; activation; cells; gene
AB THE ubiquitous Ca2+-binding protein calmodulin (CaM) is a key protein in Ca2+ homeostasis and activation of eukaryotic cells. CaM is the molecular link between free Ca2+ in the cell and the inhibition, or activation, of numerous enzymes. Many nuclear functions are under Ca2+/CaM control, and some transcriptional activators are known to be Ca2+ modulated indirectly through Ca2+/CaM-dependent protein kinases(1-4). But Ca2+/CaM has not yet been found to directly modulate any transcription factor or other DNA-binding protein. Transcription factors of the basic-helix-loop-helix (bHLK) group are important regulators in numerous systems(5-11). Here we report that binding of Ca2+-loaded CaM to the bHLH domains of several bHLH proteins directly inhibits their DNA binding. Other bHLH proteins are either less sensitive or resistant. Ca2+ ionophore selectively inhibits transcriptional activation by Ca2+/CaM-sensitive bHLH proteins in vivo, implying that Ca2+ can directly influence transcription through differential CaM inhibition of bHLH domains.
C1 UMEA UNIV,DEPT APPL CELL & MOLEC BIOL,S-90187 UMEA,SWEDEN.
C3 Umea University
NR 30
TC 149
Z9 162
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 760
EP 764
DI 10.1038/368760a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300064
PM 8152489
DA 2026-03-10
ER

PT J
AU BOLOTINA, VM
   NAJIBI, S
   PALACINO, JJ
   PAGANO, PJ
   COHEN, RA
AF BOLOTINA, VM
   NAJIBI, S
   PALACINO, JJ
   PAGANO, PJ
   COHEN, RA
TI NITRIC-OXIDE DIRECTLY ACTIVATES CALCIUM-DEPENDENT POTASSIUM CHANNELS IN VASCULAR SMOOTH-MUSCLE
SO NATURE
LA English
DT Article
ID k+ channels; skeletal-muscle; relaxing factor; endothelium; cells; relaxation; tone
AB NITRIC oxide is the major endothelium-derived relaxing factor (EDRF)(1-3), and it is thought to relax smooth muscle cells by stimulation of guanylate cyclase, accumulation of its product cyclic GMP, and cGMP-dependent modification of several intracellular processes(4-5), including activation of potassium channels through cGMP-dependent protein kinase(6,7). Here we present evidence that both exogenous nitric oxide and native EDRF can directly activate single Ca2+-dependent K+ channels (K-Ca(+)) in cell-free membrane patches without requiring cGMP. Under conditions when guanylate cyclase was inhibited by methylene blue, considerable relaxation of rabbit aorta to nitric oxide persisted which was blocked by charybdotoxin, a specific inhibitor of K-Ca(+) channels. These studies demonstrate a novel direct action of nitric oxide on K-Ca(+) channels.
RP BOLOTINA, VM (corresponding author), BOSTON UNIV,MED CTR,ROBERT DAWSON EVANS DEPT CLIN RES,VASC BIOL UNIT,BOSTON,MA 02118, USA.
NR 28
TC 1484
Z9 1618
U1 0
U2 47
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 850
EP 853
DI 10.1038/368850a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700070
PM 7512692
DA 2026-03-10
ER

PT J
AU JAN, LY
   JAN, YN
AF JAN, LY
   JAN, YN
TI POTASSIUM CHANNELS AND THEIR EVOLVING GATES
SO NATURE
LA English
DT Article
ID k+-channel; chloride channel; inward rectification; escherichia-coli; pore; inactivation; expression; subunit; voltage; region
AB Potassium channels allow potassium ions to flow across the membrane and play a key role in maintaining membrane potential. Recent research has begun to reveal how these channels transport potassium in preference to other ions, how their activity is controlled, and how they ate related to other channels.
RP JAN, LY (corresponding author), UNIV CALIF SAN FRANCISCO, HOWARD HUGHES MED INST, DEPT BIOCHEM & PHYSIOL, SAN FRANCISCO, CA 94143 USA.
NR 50
TC 263
Z9 275
U1 0
U2 17
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 119
EP 122
DI 10.1038/371119a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100053
PM 8072541
DA 2026-03-10
ER

PT J
AU OKANO, T
   YOSHIZAWA, T
   FUKADA, Y
AF OKANO, T
   YOSHIZAWA, T
   FUKADA, Y
TI PINOPSIN IS A CHICKEN PINEAL PHOTORECEPTIVE MOLECULE
SO NATURE
LA English
DT Article
ID n-acetyltransferase activity; cone visual pigments; gland; rhodopsin; invitro; identification; culture; retina; clock; light
AB IN avian pinealocytes, an environmental light signal resets the phase of the endogenous circadian pacemaker that controls the rhythmic production of melatonin(1-6). Investigation of the pineal phototransduction pathway should therefore reveal the molecular mechanism of the biological clock. The presence of rhodopsin-like photoreceptive pigment(4,5,7-9), transducin-like immunoreaction(10), and cyclic GMP-dependent cation-channel activity(11) in the avian pinealocytes suggests that there is a similarity between retinal rod cells and pinealocytes in the phototransduction pathway. We have now cloned chicken pineal cDNA encoding the photoreceptive molecule, which is 43-48% identical in amino-acid sequence to vertebrate retinal opsins. Pineal opsin, produced by transfection of complementary DNA into cultured cells, was reconstituted with 11-cis-retinal, resulting in formation of a blue-sensitive pigment (lambda(max) approximate to 470 nm). In the fight of this functional evidence and because the gene is specifically expressed only in the pineal gland, we conclude that it is a pineal photosensor and name it pinopsin.
C1 OSAKA SANGYO UNIV, FAC ENGN, DEPT INFORMAT SYST ENGN, DAITO, OSAKA 574, JAPAN.
   UNIV TOKYO, COLL ARTS & SCI, DEPT PURE & APPL SCI, BUNKYO KU, TOKYO 153, JAPAN.
C3 University of Tokyo
NR 21
TC 288
Z9 321
U1 0
U2 24
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 94
EP 97
DI 10.1038/372094a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800080
PM 7969427
DA 2026-03-10
ER

PT J
AU PARTON, RF
   VANKELECOM, IFJ
   CASSELMAN, MJA
   BEZOUKHANOVA, CP
   UYTTERHOEVEN, JB
   JACOBS, PA
AF PARTON, RF
   VANKELECOM, IFJ
   CASSELMAN, MJA
   BEZOUKHANOVA, CP
   UYTTERHOEVEN, JB
   JACOBS, PA
TI AN EFFICIENT MIMIC OF CYTOCHROME-P-450 FROM A ZEOLITE ENCAGED IRON COMPLEX IN A POLYMER MEMBRANE
SO NATURE
LA English
DT Article
ID aliphatic hydroxylation; porphyrin complexes; hydrogen-peroxide; alkane oxidation; catalysts; manganese; mechanism; pyridine
AB MANY attempts have been made to mimic the catalytic oxidative properties of the enzyme cytochrome P-450. For homogeneous systems' the mechanisms of oxidation can be readily determined but proper mimicry of the protein environment is difficult to achieve. Heterogeneous mimics have been designed that use organometallic complexes encapsulated in the supercages of zeolites(2,3), which enables control of selectivity and inhibition of auto-oxidation. But these systems do not show any mechanistic analogy with the enzymatic process, and the oxidation rates tend to be low. Here we report a composite catalytic system that achieves realistic mimicry of cytochrome P-450 as well as catalytic turnover rates that make the system industrially viable. Our catalyst incorporates iron phthalocyanine complexes encapsulated in crystals of zeolite Y, which are in turn embedded ina polydimethylsiloxane membrane. The polymer acts as a mimic of the phospholipid membrane in which cytochrome P-450 resides(4), acting as an interface between two immiscible phases and avoiding the need for solvents or phase-transfer agents. This system oxidizes alkanes at room temperature at rates comparable to those of the enzyme(5). The observation of a large kinetic isotope effect and the preferential oxidation of tertiary C-H bonds suggest close mechanistic similarities to the enzymatic process.
RP PARTON, RF (corresponding author), KATHOLIEKE UNIV LEUVEN, CENTRUM OPPERVLAKTECHEM KATALYSE, DEPT INTERFACE CHEM, B-3001 HEVERLEE, BELGIUM.
NR 32
TC 263
Z9 277
U1 1
U2 92
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 541
EP 544
DI 10.1038/370541a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700049
PM 8052309
DA 2026-03-10
ER

PT J
AU MORLA, A
   ZHANG, ZH
   RUOSLAHTI, E
AF MORLA, A
   ZHANG, ZH
   RUOSLAHTI, E
TI SUPERFIBRONECTIN IS A FUNCTIONALLY DISTINCT FORM OF FIBRONECTIN
SO NATURE
LA English
DT Article
ID cell-adhesion; metastatic cells; receptor; matrix; vitronectin; migration; integrins; peptide; surface; laminin
AB FIBRONECTIN is an extracellular matrix protein that is important in development, wound healing and tumorigenesis1-5. In the blood it is dimeric, but in tissues forms disulphide crosslinked fibrils Here we show that a fragment from the first type-III repeat of fibronectin binds to fibronectin and induces spontaneous disulphide crosslinking of the molecule into multimers of high relative molecular mass which resemble matrix fibrils. Treatment of fibronectin with this inducing fragment also converts fibronectin into a form that has greatly enhanced adhesive properties (hence the term superfibronectin) and which suppresses cell migration. Whereas cells attach to fibronectin through integrins, cell attachment to superfibronectin is mediated both by integrins and by receptors with properties distinct from those of integrins. Superfibronectin may be closely related to the natural matrix form of fibronectin.
C1 LA JOLLA CANC RES FDN,CTR CANC,LA JOLLA,CA 92037.
   UNIV CALIF SAN DIEGO,SCH MED,MOLEC PATHOL PROGRAM,LA JOLLA,CA 92037.
C3 Sanford Burnham Prebys Medical Discovery Institute; University of California System; University of California San Diego
NR 26
TC 274
Z9 321
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 193
EP 196
DI 10.1038/367193a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000067
PM 8114919
DA 2026-03-10
ER

PT J
AU CHENG, S
   CHANG, SY
   GRAVITT, P
   RESPESS, R
AF CHENG, S
   CHANG, SY
   GRAVITT, P
   RESPESS, R
TI LONG PCR
SO NATURE
LA English
DT Article
ID polymerase chain-reaction; nonpolyposis colorectal-cancer; human papillomavirus infection; dna-polymerase; amplification; homolog; type-16; gene
C1 ROCHE MOLEC SYST INC, DEPT INFECT DIS, ALAMEDA, CA 94501 USA.
RP CHENG, S (corresponding author), ROCHE MOLEC SYST INC, DEPT HUMAN GENET, ALAMEDA, CA 94501 USA.
NR 26
TC 185
Z9 272
U1 0
U2 21
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 684
EP 685
DI 10.1038/369684a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900065
PM 8208299
DA 2026-03-10
ER

PT J
AU KASHANCHI, F
   PIRAS, G
   RADONOVICH, MF
   DUVALL, JF
   FATTAEY, A
   CHIANG, CM
   ROEDER, RG
   BRADY, JN
AF KASHANCHI, F
   PIRAS, G
   RADONOVICH, MF
   DUVALL, JF
   FATTAEY, A
   CHIANG, CM
   ROEDER, RG
   BRADY, JN
TI DIRECT INTERACTION OF HUMAN TFIID WITH THE HIV-1 TRANSACTIVATOR TAT
SO NATURE
LA English
DT Article
ID human-immunodeficiency-virus; iii transcription factor; rna polymerase-ii; binding protein; elongation; components; activation; complexes; promoter; invitro
AB THE tat gene of the human immunodeficiency virus (HIV) plays a central role in the activation and life cycle of HIV. The tat protein (Tat) specifically transactivates HIV transcription in vivo and in vitro1-8, exerting its effects at the level of transcriptional initiation and elongation. Here we report that Tat binds directly to the basal transcription factor TFIID. The transcriptional activity of HeLa extracts was depleted after chromatography on a rat affinity column, which specifically retained the polymerase II-specific factor TFIID: Direct interaction of Tat with holo-TFIID, composed of TATA-binding protein (TBP) and associated factors (TAFs), was observed. Tat binds, through amino acids 36-50, directly to the TBP subunit of TFIID. Our results suggest that Tat may transduce upstream or downstream regulatory signals by direct interaction with the basal transcription factor TFIID.
C1 MASSACHUSETTS GEN HOSP,CTR CANC,BOSTON,MA 02129.
   ROCKEFELLER UNIV,NEW YORK,NY 10021.
C3 Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Rockefeller University
RP KASHANCHI, F (corresponding author), NCI,MOLEC VIROL LAB,BETHESDA,MD 20892, USA.
NR 30
TC 248
Z9 262
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 295
EP 299
DI 10.1038/367295a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400063
PM 8121496
DA 2026-03-10
ER

PT J
AU ALLARD, P
   CARBONNELLE, J
   METRICH, N
   LOYER, H
   ZETTWOOG, P
AF ALLARD, P
   CARBONNELLE, J
   METRICH, N
   LOYER, H
   ZETTWOOG, P
TI SULFUR OUTPUT AND MAGMA DEGASSING BUDGET OF STROMBOLI VOLCANO
SO NATURE
LA English
DT Article
ID sulfur-dioxide; basaltic magmas; emissions; atmosphere; etna
AB STROMBOLI volcano in the Aeolian islands has been erupting continuously for more than 2,000 years(1), and probably as many as 5,000, following a major flank collapse(2,3). Here we describe air-borne measurements of the plume flux of SO2 during 1980-93, which show that the volcano emits very large amounts of gas, mostly by open-conduit degassing between explosive outbursts, while exuding little basalt. Microprobe analysis of sulphur in the K-rich (shoshonitic) basalt, along with data for primitive basalts in the region(4,5), suggests that the time-averaged SO2 flux is produced by intrusive degassing of 0.01-0.02 km(3) yr(-1) of magma, 100-200 times more than the volume erupted. Over 5,000 years, this rate implies that 50-100 km(3) of intruded basalt would have been degassed, suggesting either that the volcanic pile has grown substantially by intrusion(6) or, more probably, that a large magma storage system is emplaced at a shallow level within the crustal basement. Our results indicate that Etna and Stromboli alone provide 10% of the global budget of volcanic SO2.
C1 IPSN,CEA,F-91191 SACLAY,FRANCE.
   CEA,CNRS,LAB PIERRE SUE,F-91191 SACLAY,FRANCE.
C3 CEA; CEA; Centre National de la Recherche Scientifique (CNRS)
RP ALLARD, P (corresponding author), CEA,CNRS,CTR FAIBLES RADIOACT,F-91198 GIF SUR YVETTE,FRANCE.
NR 40
TC 307
Z9 319
U1 1
U2 37
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 326
EP 330
DI 10.1038/368326a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500043
DA 2026-03-10
ER

PT J
AU SCHLUTER, H
   OFFERS, E
   BRUGGEMANN, G
   VANDERGIET, M
   TEPEL, M
   NORDHOFF, E
   KARAS, M
   SPIEKER, C
   WITZEL, H
   ZIDEK, W
AF SCHLUTER, H
   OFFERS, E
   BRUGGEMANN, G
   VANDERGIET, M
   TEPEL, M
   NORDHOFF, E
   KARAS, M
   SPIEKER, C
   WITZEL, H
   ZIDEK, W
TI DIADENOSINE PHOSPHATES AND THE PHYSIOLOGICAL CONTROL OF BLOOD-PRESSURE
SO NATURE
LA English
DT Article
ID bovine adrenal-medulla; essential hypertensives; chromaffin cells; induced release; ap4a; polyphosphates; tetraphosphate; chromatography; endothelium; nucleotides
AB OUR understanding of the regulation of vascular tone has been extended since the identification of vasoactive agents such as the atrial natriuretic peptides1, endothelial-derived relaxing factor2 and endothelin3. Unidentified vasopressive agents have been found in platelets4. Here we isolate these vasopressors and identify them as diadenosine pentaphosphate (AP5A) and diadenosine hexaphosphate (AP6A) by chromatography, mass spectrometry, ultraviolet spectroscopy and enzymatic cleavage. In the vasculature of isolated perfused rat kidney, both diadenosine phosphates were active at a concentration of 10(-9) M; in aortic rings, contractions were elicited at 10(-8) M. Intra-aortic injection in the rat caused a prolonged increase in blood pressure. We conclude that AP5A and AP6A may play a part in local vasoregulation and possibly in the regulation of blood pressure.
C1 UNIV MUNSTER,INST BIOCHEM,MED POLIKLIN,D-48129 MUNSTER,GERMANY.
C3 University of Munster
RP SCHLUTER, H (corresponding author), UNIV MUNSTER,INST MED PHYS,MED POLIKLIN,ALBERT SCHWEITZER STR 33,D-48129 MUNSTER,GERMANY.
NR 23
TC 205
Z9 213
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 186
EP 188
DI 10.1038/367186a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000065
PM 8114917
DA 2026-03-10
ER

PT J
AU CHEN, H
   HE, Y
   SHIFLET, GJ
   POON, SJ
AF CHEN, H
   HE, Y
   SHIFLET, GJ
   POON, SJ
TI DEFORMATION-INDUCED NANOCRYSTAL FORMATION IN SHEAR BANDS OF AMORPHOUS-ALLOYS
SO NATURE
LA English
DT Article
ID metallic glasses; mechanical-property; aluminum; crystallization
AB AMORPHOUS alloys formed by rapid solidification of a metallic melt are of considerable technological interest as high-strength materials1-8. As they are not in thermodynamic equilibrium, these materials tend to crystallize on heating9,10. A high degree of crystallization leads to embrittlement, but if it can be arrested when the crystallites are of only nanometre dimensions, the resulting amorphous-nanocrystalline composite actually has greater strength than the original amorphous material11. There is consequently much interest in understanding the mechanisms of crystallization. Previous studies have suggested that mechanical deformation can induce crystallization12-16. Here we report the direct observation of crystallization within the shear bands of aluminium-based amorphous alloys induced by bending. The crystals are face-centred cubic aluminium, 7-10 nm in diameter, and seem to form as a consequence of local atomic rearrangements in regions of high plastic strain. We suggest that mechanical deformation might therefore be used to form high-strength amorphous-nanocrystalline composites.
C1 UNIV VIRGINIA,DEPT MAT SCI & ENGN,CHARLOTTESVILLE,VA 22901.
   UNIV VIRGINIA,DEPT PHYS,CHARLOTTESVILLE,VA 22901.
C3 University of Virginia; University of Virginia
NR 29
TC 496
Z9 536
U1 3
U2 166
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 541
EP 543
DI 10.1038/367541a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300052
DA 2026-03-10
ER

PT J
AU KATZ, PS
   GETTING, PA
   FROST, WN
AF KATZ, PS
   GETTING, PA
   FROST, WN
TI DYNAMIC NEUROMODULATION OF SYNAPTIC STRENGTH INTRINSIC TO A CENTRAL PATTERN GENERATOR CIRCUIT
SO NATURE
LA English
DT Article
ID central nervous-system; motor organization; neural networks; tritonia; neurons; behavior; aplysia; modulation; interneurons; mechanisms
AB MOTOR circuits are often thought to be physically separate from their neuromodulatory systems1,2. We report here a counter example, where neurons within a circuit appear to modulate synaptic properties of that same circuit during its normal operation. The dorsal swim interneurons (DSIs) are members of the central pattern generator circuit for escape swimming in the mollusc Tritonia diomedea3. However, DSI stimulation also rapidly enhances the synaptic potentials evoked by another neuron in the same circuit onto its follower cells. This modulatory action appears to be mediated by serotonin (5-hydroxytryptamine); the DSIs are serotonin-immunoreactive4, and bath-application of serotonin mimics and occludes the effect of DSIs. These results indicate that during the escape swim, circuit connection strengths are dynamically controlled by the activity of neurons within the circuit itself. This 'intrinsic neuromodulation' may be important for the animal's initial decision to swim, the generation of the swim motor programme itself, and certain types of learning.
C1 UNIV IOWA, DEPT PHYSIOL & BIOPHYS, IOWA CITY, IA 52242 USA.
C3 University of Iowa
RP KATZ, PS (corresponding author), UNIV TEXAS, SCH MED, DEPT NEUROBIOL & ANAT, HOUSTON, TX 77225 USA.
NR 30
TC 128
Z9 142
U1 0
U2 8
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 729
EP 731
DI 10.1038/367729a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100056
PM 8107867
DA 2026-03-10
ER

PT J
AU LIMA, CD
   WANG, JC
   MONDRAGON, A
AF LIMA, CD
   WANG, JC
   MONDRAGON, A
TI 3-DIMENSIONAL STRUCTURE OF THE 67K N-TERMINAL FRAGMENT OF ESCHERICHIA-COLI DNA TOPOISOMERASE-I
SO NATURE
LA English
DT Article
ID ray-diffraction data; escherichia-coli; macromolecular crystallography; type-1 topoisomerases; crystal-structures; active-site; protein; binding; resolution; identification
AB The three-dimensional structure of the 67K amino-terminal fragment of Escherichia coli DNA topoisomerase I has been determined to 2.2 angstrom resolution. The polypeptide folds in an unusual way to give four distinct domains enclosing a hole large enough to accommodate a double-stranded DNA. The active-site tyrosyl residue, which is involved in the transient breakage of a DNA strand and the formation of a covalent enzyme-DNA intermediate, is present at the interface of two domains. The structure suggests a plausible mechanism by which E. coli DNA topoisomerase I and other members of the same DNA topoisomerase subfamily could catalyse the passage of one DNA strand through a transient break in another strand.
C1 HARVARD UNIV,DEPT BIOCHEM & MOLEC BIOL,7 DIVIN AVE,CAMBRIDGE,MA 02138.
   NORTHWESTERN AVE,DEPT BIOCHEM MOLEC BIOL & CELL BIOL,EVANSTON,IL 60208.
C3 Harvard University
FU NIGMS NIH HHS [R01 GM051350] Funding Source: Medline
NR 62
TC 278
Z9 310
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 138
EP 146
DI 10.1038/367138a0
PG 9
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000050
PM 8114910
DA 2026-03-10
ER

PT J
AU KRAANKORTEWEG, RC
   LOAN, AJ
   BURTON, WB
   LAHAV, O
   FERGUSON, HC
   HENNING, PA
   LYNDENBELL, D
AF KRAANKORTEWEG, RC
   LOAN, AJ
   BURTON, WB
   LAHAV, O
   FERGUSON, HC
   HENNING, PA
   LYNDENBELL, D
TI DISCOVERY OF A NEARBY SPIRAL GALAXY BEHIND THE MILKY-WAY
SO NATURE
LA English
DT Article
ID local group; distance; maffei-1
AB THE disk of the Milky Way contains a lot of gas and dust, which obscures about 20% of the extragalactic sky. Galaxies hidden behind the Milky Way may have an important influence on the dynamics of the Local Group and its peculiar motion relative to the cosmic microwave background radiation(1,2). Here we report the discovery of a large spiral galaxy, which we call Dwingeloo 1, during the course of a search for emission from atomic hydrogen (H I) associated with galaxies hidden by the disk of the Milky Way-such H I emission is not obscured by the disk if the velocity of tbe emission differs from that of the local gas(3). The nea galaxy seems to be associated with the group containing IC342 and the Maffei galaxies, and a subsequent optical image suggests that it is of type SBb. The detection of Dwingeloo 1 early in the course of this survey suggests that many more galaxies hidden behind the Milky Way remain to be discovered.
C1 UNIV CAMBRIDGE,INST ASTRON,CAMBRIDGE CB3 0HA,ENGLAND.
   LEIDEN OBSERV,2300 RA LEIDEN,NETHERLANDS.
   SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218.
   UNIV NEW MEXICO,DEPT PHYS & ASTRON,ALBUQUERQUE,NM 87131.
C3 University of Cambridge; Leiden University; Leiden University - Excl LUMC; Space Telescope Science Institute; University of New Mexico
RP KRAANKORTEWEG, RC (corresponding author), KAPTEYN ASTRON INST,POSTBUS 800,9700 AV GRONINGEN,NETHERLANDS.
NR 25
TC 72
Z9 74
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 77
EP 79
DI 10.1038/372077a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800073
DA 2026-03-10
ER

PT J
AU CAELLES, C
   HELMBERG, A
   KARIN, M
AF CAELLES, C
   HELMBERG, A
   KARIN, M
TI P53-DEPENDENT APOPTOSIS IN THE ABSENCE OF TRANSCRIPTIONAL ACTIVATION OF P53-TARGET GENES
SO NATURE
LA English
DT Article
ID replication factor-a; dna-replication; thymocyte apoptosis; cell-death; wild-type; p53; protein; mutant; transformation; localization
AB THE tumour suppressor p53 is required to induce programmed cell death (apoptosis) by DNA-damaging agents(1,2). As p53 is a transcriptional activator(3) that mediates gene induction after DNA damage(4), it has been proposed to be a genetic switch that activates apoptosis-mediator genes(5). Here we evaluate the role of p53 in DNA-damage-induced apoptosis by establishing derivatives of GHFT1 cells, that are somatotropic progenitors immortalized by expression of SV40 T-antigen(6), which express a temperature-sensitive p53 mutant(7). In these cells induction of apoptosis by DNA damage depends strictly on p53 function. A shift to the permissive temperature triggers apoptosis following DNA damage, but this is independent of new RNA or protein synthesis. The extent of apoptotic DNA cleavage is directly proportional to the period during which p53 is functional. These results do not support the proposal that p53 is an activator of apoptosis-mediator genes but rather indicate that p53 either represses genes necessary for cell survival(8) or is a component of the enzymatic machinery for apoptotic cleavage or repair of DNA(5).
C1 UNIV CALIF SAN DIEGO,SCH MED,CTR MOLEC GENET,DEPT PHARMACOL,PROGRAM BIOMED SCI,LA JOLLA,CA 92093.
C3 University of California System; University of California San Diego
NR 33
TC 857
Z9 930
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 220
EP 223
DI 10.1038/370220a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100054
PM 8028670
DA 2026-03-10
ER

PT J
AU WANG, SX
   HAZELRIGG, T
AF WANG, SX
   HAZELRIGG, T
TI IMPLICATIONS FOR BCD MESSENGER-RNA LOCALIZATION FROM SPATIAL-DISTRIBUTION OF EXU PROTEIN IN DROSOPHILA OOGENESIS
SO NATURE
LA English
DT Article
ID messenger-rna localization; bicoid rna; gene; microtubules; differentiation; morphogen; transport; gradient; pattern; embryos
AB SUBCELLULAR RNA localization in different cell types leads to asymmetric distribution of proteins in these cells(1,2). The localization of bicoid (bcd) messenger RNA to the anterior pole of the developing Drosophila oocyte gives rise in embryogenesis to a steep concentration gradient of the bcd protein(3-6), a transcription factor that activates expression of zygotic genes needed for anterior development(7-9). The exuperantia (exu) gene is necessary for this localization of bcd mRNA(3,4). Here we express a chimaeric gene encoding a fusion between the Acquorea victoria green fluorescent protein (GPP)(10) and the exu protein (Exu) in female germ cells, and find that the fusion protein fluoresces strongly in both live and fixed cells during Drosophila oogenesis. The fusion protein rescues an exu null allele, restoring full fertility to females, and is expressed and localized in a temporal and spatial pattern similar to native Exu. The high sensitivity of the GFP tag provides important ne,v details on the subcellular localization of Exu. The fusion protein is found in particles concentrated at ring canals, where transport occurs between nurse cells and the oocyte. Drugs such as colchicine and taxol that affect microtubule stability alter localization of the particles. We propose that the particles are ribonucleoprotein complexes or vesicles which transport bcd mRNA along microtubules and target it to the anterior oocyte cortex.
C1 COLUMBIA UNIV,DEPT BIOL SCI,NEW YORK,NY 10027.
C3 Columbia University
NR 25
TC 435
Z9 540
U1 0
U2 52
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 400
EP 403
DI 10.1038/369400a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400057
PM 7910952
DA 2026-03-10
ER

PT J
AU MARSHALL, H
   STUDER, M
   POPPERL, H
   APARICIO, S
   KUROIWA, A
   BRENNER, S
   KRUMLAUF, R
AF MARSHALL, H
   STUDER, M
   POPPERL, H
   APARICIO, S
   KUROIWA, A
   BRENNER, S
   KRUMLAUF, R
TI A CONSERVED RETINOIC ACID RESPONSE ELEMENT REQUIRED FOR EARLY EXPRESSION OF THE HOMEOBOX GENE HOXB-1
SO NATURE
LA English
DT Article
ID central-nervous-system; xenopus embryos; mouse hindbrain; pattern; identification; hox-2.9; transformation; segmentation; rhombomeres; receptors
AB WITHIN the Herb homeobox gene complex, Hoxb-1 is the earliest member expressed in the mesoderm and neuroectoderm of primitive streak and presomite embryos, preceding rhombomere-restricted expression in the hindbrain(1-7). Ectopic exposure of embryos to retinoic acid alters spatial aspects of Hox gene expression patterns(8-15). However, the role of retinoids in regulating these genes during normal development is unclear. We have now identified two enhancers, 3' of the mouse Hoxb-1 gene, which together reconstruct the early endogenous expression pattern and mediate the early ectopic response to retinoic acid. Furthermore, these regions are functionally conserved in both chicken and pufferfish (Fugu rubripes)(16) Hoxb-1 genes. The enhancer that controls the retinoic acid response, and regulates expression predominantly in neuroectoderm, contains a retinoic acid response element (RARE). Point mutations in the RARE abolish expression in neuroectoderm. Therefore, this RARE is not only involved in the ectopic response to retinoic acid, but is also essential for establishing aspects of the early Hoxb-1 expression pattern.
C1 NATL INST MED RES,DEV NEUROBIOL LAB,LONDON NW7 1AA,ENGLAND.
   UNIV CAMBRIDGE,ADDENBROOKES HOSP,SCH CLIN,MOLEC GENET UNIT,CAMBRIDGE CB2 2QQ,ENGLAND.
   UNIV CAMBRIDGE,ADDENBROOKES HOSP,SCH CLIN,DEPT MED,CAMBRIDGE CB2 2QQ,ENGLAND.
   NAGOYA UNIV,SCH SCI,DEPT MOLEC BIOL,CHIKUSA KU,NAGOYA 46401,JAPAN.
C3 MRC National Institute for Medical Research; University of Cambridge; Cambridge University Hospitals NHS Foundation Trust; Addenbrooke's Hospital; Cambridge University Hospitals NHS Foundation Trust; Addenbrooke's Hospital; University of Cambridge; Nagoya University
NR 30
TC 396
Z9 434
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 567
EP 571
DI 10.1038/370567a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700058
PM 7914354
DA 2026-03-10
ER

PT J
AU WAGNER, RW
AF WAGNER, RW
TI GENE INHIBITION USING ANTISENSE OLIGODEOXYNUCLEOTIDES
SO NATURE
LA English
DT Article
ID nf-kappa-b; in-vivo; oligonucleotides; expression; invivo; leukemia; virus; selection; molecules; invitro
AB Antisense oligodeoxynucleotides (ODNs) have great promise as agents for the specific manipulation of gene expression. Until recently, nonspecific effects of ODNs often confounded the interpretation of antisense studies. Improvements in ODN chemistry and cellular delivery techniques now allow for more potent and specific gene inhibition. This review critically evaluates recent progress in the development of antisense ODNs.
RP WAGNER, RW (corresponding author), GILEAD SCI,353 LAKESIDE DR,FOSTER CITY,CA 94404, USA.
NR 53
TC 807
Z9 1086
U1 1
U2 35
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 333
EP 335
DI 10.1038/372333a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700046
PM 7969490
DA 2026-03-10
ER

PT J
AU MURAKAMI, T
   TANAKA, Y
   KULKARNI, SR
   OGASAKA, Y
   SONOBE, T
   OGAWARA, Y
   AOKI, T
   YOSHIDA, A
AF MURAKAMI, T
   TANAKA, Y
   KULKARNI, SR
   OGASAKA, Y
   SONOBE, T
   OGAWARA, Y
   AOKI, T
   YOSHIDA, A
TI X-RAY-IDENTIFICATION OF THE SOFT GAMMA-RAY REPEATER 1806-20
SO NATURE
LA English
DT Article
ID high-energy transient
AB THE nature of gamma-ray bursters-astrophysical sources that emit abrupt bursts of gamma-rays-presents a long-standing question in high-energy astronomy. Soft gamma-ray repeaters (SGRs) are distinguished from classical gamma-ray bursters by the short duration, softer gamma-ray spectrum and recurrent activity of their outbursts(1-6). Millisecond-scale structure in these bursts suggests that SGRs are compact, and many models invoke neutron stars as the emitting objects(1,5). This idea is supported by the association of two SGRs, SGR0526-66 (ref. 6) and SGR1806-20 (ref. 7), with supernova remnants, SNR N49 and the radio nebula G10.0-0.3 respectively. Very recently, Kulkarni et al.(8,9) have suggested that a compact radio source in G10.0-0.3 corresponds to a young pulsar at the centre of this nebula, and can be identified with SGR1806-20. Here we report the detection of a burst from SGR1806-20 with the X-ray satellite ASCA(10), which allows us to identify the burster with a new X-ray source which we designate AX1805.7-2025. The burst is coincident in time with that detected by the BATSE(11,12) instrument on board the Compton Gamma Ray Observatory. This result provides strong evidence that SGRs are indeed neutron stars.
C1 CALTECH,PASADENA,CA 91125.
   INST PHYS & CHEM RES,WAKO,SAITAMA 351,JAPAN.
C3 California Institute of Technology; RIKEN
RP MURAKAMI, T (corresponding author), INST SPACE & ASTRONAUT SCI,3-1-1 YOSHINODAI,SAGAMIHARA,KANAGAWA 229,JAPAN.
NR 15
TC 142
Z9 151
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 127
EP 129
DI 10.1038/368127a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000058
DA 2026-03-10
ER

PT J
AU BROWN, CJ
   WILLARD, HF
AF BROWN, CJ
   WILLARD, HF
TI THE HUMAN X-INACTIVATION CENTER IS NOT REQUIRED FOR MAINTENANCE OF X-CHROMOSOME INACTIVATION
SO NATURE
LA English
DT Article
ID xist gene; localization; expression; nucleus; region; locus; cells
AB X-CHROMOSOME inactivation occurs early in mammalian female development to achieve dosage compensation with males(1). Although it is widely accepted that this inactivation requires the presence in cis of the X-inactivation centre (XIC)(2-5), it is not known whether the XIC is required for the initiation, promulgation or maintenance of X inactivation(6,7). The XIST gene, which is localized within the XIC interval on both the human and mouse X chromosomes, is constitutively expressed from inactive X chromosomes(8-10), suggesting a possible role in the maintenance of X inactivation. To address whether the presence of the XIC, including the XIST gene, is continuously required for the maintenance of X-chromosome inactivation, we have analysed the transcriptional activity of a number of X-linked genes in mouse/human somatic cell hybrids retaining an intact human inactive X chromosome or derivatives of the inactive X chromosome lacking the XIC. Genes subject to X inactivation remain transcriptionally silent despite the loss of the XIC, demonstrating that the presence of the XIC is not required for the maintenance of X inactivation in somatic cells.
RP BROWN, CJ (corresponding author), CASE WESTERN RESERVE UNIV,CTR HUMAN GENET,DEPT GENET,10900 EUCLID AVE,CLEVELAND,OH 44106, USA.
NR 26
TC 250
Z9 288
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 154
EP 156
DI 10.1038/368154a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000068
PM 8139659
DA 2026-03-10
ER

PT J
AU FUJITA, A
   OKA, C
   ARIKAWA, Y
   KATAGAI, T
   TONOUCHI, A
   KUHARA, S
   MISUMI, Y
AF FUJITA, A
   OKA, C
   ARIKAWA, Y
   KATAGAI, T
   TONOUCHI, A
   KUHARA, S
   MISUMI, Y
TI A YEAST GENE NECESSARY FOR BUD-SITE SELECTION ENCODES A PROTEIN SIMILAR TO INSULIN-DEGRADING ENZYMES
SO NATURE
LA English
DT Article
ID escherichia-coli; saccharomyces-cerevisiae; expression; sequence; cloning; disruption
AB CELLS Of the yeast Saccharomyces cerevisiae choose bud sites in a non-random spatial pattern that depends on mating type: axial for haploid cells and bipolar for ala diploid cells(1,2). We identified a mutant yeast, axl1, in which the budding pattern is altered from axial to bipolar. Expression of the AXL1 gene is repressed in a/alpha diploid cells. With the ectopic expression of AXL1, a/alpha cells exhibited an axial budding pattern, thus AXL1 is a key morphological determinant that distinguishes the budding pattern of haploid cells from that of ala diploid cells(2). AXL1 encodes a protein similar in sequence to the human and Drosophila insulin-degrading enzymes(3,4) and to the Escherichia coli ptr gene product(5). The axial budding pattern might result from degradation of a target protein by the putative Axl1 protease.
C1 IND RES INST CHIBA PREFECTURE, WAKABA KU, CHIBA 264, JAPAN.
   NAGANO STATE LAB FOOD TECHNOL, NAGANO 380, JAPAN.
   KYUSHU UNIV, GRAD SCH GENET RESOURCES TECHNOL, HIGASHI KU, FUKUOKA 812, JAPAN.
   FUKUOKA UNIV, SCH MED, DEPT BIOCHEM, JONAN KU, FUKUOKA 81401, JAPAN.
C3 Kyushu University; Fukuoka University
RP FUJITA, A (corresponding author), AGCY IND SCI & TECHNOL, NATL INST BIOSCI & HUMAN TECHNOL, 1-1 HIGASHI, TSUKUBA, IBARAKI 305, JAPAN.
NR 21
TC 117
Z9 134
U1 0
U2 7
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 567
EP 570
DI 10.1038/372567a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200057
PM 7990931
DA 2026-03-10
ER

PT J
AU TANEV, PT
   CHIBWE, M
   PINNAVAIA, TJ
AF TANEV, PT
   CHIBWE, M
   PINNAVAIA, TJ
TI TITANIUM-CONTAINING MESOPOROUS MOLECULAR-SIEVES FOR CATALYTIC-OXIDATION OF AROMATIC-COMPOUNDS
SO NATURE
LA English
DT Article
ID silicalite
AB TITANIUM silicalite is an effective molecular-sieve catalyst for the selective oxidation of alkanes, the hydroxylation of phenol and the epoxidation of alkenes in the presence of H2O2 (refs 1-3). The range of organic compounds that can be oxidized is greatly limited, however, by the relatively small pore size (about 0.6 nm) of the host framework(4). Large-pore (mesoporous) silica-based molecular sieves have been prepared recently by Kresge et al.(5-7) and Kuroda et al.(8); the former used a templating approach in which the formation of an inorganic mesoporous structure is assisted by self-organization of surfactants, and the latter involved topochemical rearrangement of a layered silica precursor. Here we describe the use of the templating approach to synthesize mesoporous silica-based molecular sieves partly substituted with titanium-large-pore analogues of titanium silicalite. We find that these materials show selective catalytic activity towards the oxidation of 2,6-di-tert-butyl phenol to the corresponding quinone and the conversion of benzene to phenol.
C1 MICHIGAN STATE UNIV, DEPT CHEM, E LANSING, MI 48824 USA.
   MICHIGAN STATE UNIV, CTR FUNDAMENTAL MAT RES, E LANSING, MI 48824 USA.
C3 Michigan State University; Michigan State University
NR 14
TC 1661
Z9 1821
U1 6
U2 543
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 321
EP 323
DI 10.1038/368321a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500041
PM 8127366
DA 2026-03-10
ER

PT J
AU LORENZO, A
   RAZZABONI, B
   WEIR, GC
   YANKNER, BA
AF LORENZO, A
   RAZZABONI, B
   WEIR, GC
   YANKNER, BA
TI PANCREATIC-ISLET CELL TOXICITY OF AMYLIN ASSOCIATED WITH TYPE-2 DIABETES-MELLITUS
SO NATURE
LA English
DT Article
ID amyloid polypeptide; alzheimers-disease; skeletal-muscle; hormone; langerhans; sequence; peptide; protein; death
AB THE 37-amino-acid polypeptide amylin is the principal constituent of the amyloid deposits that form in the islets of Langerhans in patients with type-2 diabetes menitus(1-5), but its role in the pathogenesis of this disease is unresolved(6-8). In view of the fact that the beta-amyloid protein that forms fibrils in Alzheimer's disease is toxic to neurons(9,10), we have investigated whether amylin fibrils could be toxic to pancreatic islet cells. We show here that human amylin is toxic to insulin-producing beta-cells of the adult pancreas of rats and humans. This toxicity is mediated by the fibrillar form of the amylin peptide and requires direct contact of the fibrils with the cell surface. The mechanism of cell death involves RNA and protein synthesis and is characterized by plasma membrane-blebbing, chromatin condensation and DNA fragmentation, indicating that amylin induces islet cell apoptosis. These findings indicate that amylin fibril formation in the pancreas may cause islet cell dysfunction and death in type-2 diabetes mellitus.
C1 HARVARD UNIV,SCH MED,DEPT NEUROL,BOSTON,MA 02115.
   CHILDRENS HOSP MED CTR,BOSTON,MA 02115.
   JOSLIN DIABET CTR,BOSTON,MA 02215.
   HARVARD UNIV,SCH MED,BOSTON,MA 02215.
C3 Harvard University; Harvard Medical School; Harvard University; Harvard University Medical Affiliates; Boston Children's Hospital; Harvard University; Harvard University Medical Affiliates; Joslin Diabetes Center, Inc.; Harvard University; Harvard Medical School
NR 29
TC 745
Z9 845
U1 0
U2 80
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 756
EP 760
DI 10.1038/368756a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300063
PM 8152488
DA 2026-03-10
ER

PT J
AU YIN, XM
   OLTVAI, ZN
   KORSMEYER, SJ
AF YIN, XM
   OLTVAI, ZN
   KORSMEYER, SJ
TI BH1 AND BH2 DOMAINS OF BCL-2 ARE REQUIRED FOR INHIBITION OF APOPTOSIS AND HETERODIMERIZATION WITH BAX
SO NATURE
LA English
DT Article
ID programmed cell-death; chromosomal breakpoint; protooncogene bcl-2; sequence similarity; gene; protein; expression; survival; thymocytes; prevention
AB BCL-2 was isolated from the t(14;18) chromosomal breakpoint in follicular B-cell lymphoma(1-3). Bcl-2 has the unique oncogenic role of extending cell survival by inhibiting a variety of apoptotic deaths(4-13). An emerging family of Bcl-2 -related proteins share two highly conserved regions(14-20) referred to here as Bcl-2 homology 1 and 2 (BH1 and BH2) domains (Fig. 1). This includes Bax which heterodimerizes with Bcl-2 and when overexpressed counteracts Bcl-2(14). We report here that site-specific mutagenesis of Bcl-2 establishes the two domains as novel dimerization motifs. Substitution of Gly 145 in BH1 domain or Trp 188 in BH2 domain completely abrogated Bcl-2's death-repressor activity in interleukin-3 deprivation, gamma-irradiation and glucocorticoid-induced apoptosis. Mutations that affected Bcl-2's function also disrupted its heterodimerization with Bax, yet still permitted Bcl-2 homodimerization. These results establish a functional role for the BH1 and BH2 domains and suggest Bcl-2 exerts its action through heterodimerization with Bax.
RP YIN, XM (corresponding author), WASHINGTON UNIV,SCH MED,HOWARD HUGHES MED INST,DIV MOLEC ONCOL,ST LOUIS,MO 63110, USA.
NR 30
TC 1223
Z9 1423
U1 0
U2 31
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 321
EP 323
DI 10.1038/369321a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900050
PM 8183370
DA 2026-03-10
ER

PT J
AU YU, RT
   MCKEOWN, M
   EVANS, RM
   UMESONO, K
AF YU, RT
   MCKEOWN, M
   EVANS, RM
   UMESONO, K
TI RELATIONSHIP BETWEEN DROSOPHILA GAP GENE TAILLESS AND A VERTEBRATE NUCLEAR RECEPTOR TLX
SO NATURE
LA English
DT Article
ID 9-cis retinoic acid; embryonic termini; dna-binding; superfamily; expression; cloning; region; brain; sites; cell
AB We report here the identification of a unique vertebrate nuclear receptor, Tlx, which is expressed exclusively in the neuroepithelium of the embryonic brain. Sequence comparison reveals striking similarity to the product of the Drosophila terminal/gap gene tailless (tll)(1), which is expressed in the embryonic brain and is required for brain development in flies. In vitro DNA-binding assays demonstrated that Tlx and Tll proteins share a target gene specificity that, is unique among the nuclear receptor superfamily. Ectopic expression of Tlx in fly embryos caused a repression of segmentation comparable to that elicited by Tll. The similarities in structure, expression pattern, target gene specificity and phenotypes in transgenic flies suggest conservation of genetic programs upstream and downstream of this Tlx/Tll class of nuclear receptors during embryogenesis.
C1 SALK INST BIOL STUDIES,HOWARD HUGHES MED INST,GENE EXPRESS LAB,LA JOLLA,CA 92037.
   SALK INST BIOL STUDIES,MOLEC BIOL & VIROL LAB,LA JOLLA,CA 92037.
   UNIV CALIF SAN DIEGO,GRAD PROGRAM MOLEC PATHOL,LA JOLLA,CA 92037.
C3 Howard Hughes Medical Institute; Salk Institute; Salk Institute; University of California System; University of California San Diego
NR 28
TC 166
Z9 194
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 375
EP 379
DI 10.1038/370375a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400057
PM 8047143
DA 2026-03-10
ER

PT J
AU SUNDA, WG
   KIEBER, DJ
AF SUNDA, WG
   KIEBER, DJ
TI OXIDATION OF HUMIC SUBSTANCES BY MANGANESE OXIDES YIELDS LOW-MOLECULAR-WEIGHT ORGANIC SUBSTRATES
SO NATURE
LA English
DT Article
ID natural-waters; dissolution; reduction; seawater; sediments; bacteria; acid
AB MANY bacteria oxidize thermodynamically unstable manganese(II) to Mn oxides and deposit the oxides on their surfaces1,2, a process that appears to account for most Mn oxidation in natural waters3-5 and sediments6. Among the reasons that have been proposed for the evolutionary selection of this process are protection from damage by toxic metals and oxygen species, protection from ultraviolet light, and strengthening of the bacterial sheath or capsule1,7. Mn oxides may promote harmful free radical reactions, however, and marine Mn-oxidizing bacteria are particularly susceptible to photoinhibition8. Here we report that Mn oxides lyse complex humic substances, which in general cannot be used by microorganisms directly9-11, to form low-molecular-weight organic compounds that can be used as substrates for microbial growth. Mn-oxidizing bacteria may thus be able to use the carbon pool in humic substances, which represent one of the largest organic reservoirs in natural waters, sediments and soils.
C1 SUNY COLL ENVIRONM SCI & FORESTRY,DEPT CHEM,SYRACUSE,NY 13210.
C3 State University of New York (SUNY) System; State University of New York (SUNY) College of Environmental Science & Forestry
RP SUNDA, WG (corresponding author), NOAA,NATL MARINE FISHERIES SERV,101 PIVERS ISL RD,BEAUFORT,NC 28516, USA.
NR 21
TC 304
Z9 354
U1 1
U2 195
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 62
EP 64
DI 10.1038/367062a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500058
DA 2026-03-10
ER

PT J
AU BULLOUGH, PA
   HUGHSON, FM
   SKEHEL, JJ
   WILEY, DC
AF BULLOUGH, PA
   HUGHSON, FM
   SKEHEL, JJ
   WILEY, DC
TI STRUCTURE OF INFLUENZA HEMAGGLUTININ AT THE PH OF MEMBRANE-FUSION
SO NATURE
LA English
DT Article
ID virus hemagglutinin; conformational change; protein models; activation; acid; glycoprotein; antibody; hemolysis; mechanism; resolution
AB Low pH induces a conformational change in the influenza virus haemagglutinin, which then mediates fusion of the viral and host cell membranes. The three-dimensional structure of a fragment of the haemagglutinin in this conformation reveals a major refolding of the secondary and tertiary structure of the molecule. The apolar fusion peptide moves at least 100 Angstrom to one tip of the molecule. At the other end a helical segment unfolds, a subdomain relocates reversing the chain direction, and part of the structure becomes disordered.
C1 HARVARD UNIV,DEPT BIOCHEM & MOLEC BIOL,CAMBRIDGE,MA 02138.
   HARVARD UNIV,HOWARD HUGHES MED INST,CAMBRIDGE,MA 02138.
   NATL INST MED RES,LONDON NW7 1AA,ENGLAND.
C3 Harvard University; Howard Hughes Medical Institute; Harvard University; MRC National Institute for Medical Research
NR 50
TC 1422
Z9 1689
U1 2
U2 195
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 37
EP 43
DI 10.1038/371037a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100042
PM 8072525
DA 2026-03-10
ER

PT J
AU HEDIN, LO
   GRANAT, L
   LIKENS, GE
   BUISHAND, TA
   GALLOWAY, JN
   BUTLER, TJ
   RODHE, H
AF HEDIN, LO
   GRANAT, L
   LIKENS, GE
   BUISHAND, TA
   GALLOWAY, JN
   BUTLER, TJ
   RODHE, H
TI STEEP DECLINES IN ATMOSPHERIC BASE CATIONS IN REGIONS OF EUROPE AND NORTH-AMERICA
SO NATURE
LA English
DT Article
ID eastern-united-states; precipitation chemistry; spruce; acidity; calcium; waters; ratios
AB HUMAN activities have caused marked changes in atmospheric chemistry over large regions of Europe and North America. Although considerable attention has been paid to the effects of changes in the deposition of acid anions (such as sulphate and nitrate) on terrestrial and aquatic ecosystems1-7, little is known about whether the concentrations of basic components of the atmosphere have changed over time8,9 and what the biogeochemical consequences of such potential changes might be. In particular, there has been some controversy8-12 as to whether declines in base-cation deposition have countered effects of recent reductions in SO2 emission. Here we report evidence for steep declines in the atmospheric concentrations of base cations (sum of non-sea-salt Ca2+, Mg2+, K+ and Na+) over the past 10 to 26 years from high-quality precipitation chemistry records in Europe and North America. To varying but generally significant degrees, these base-cation trends have offset recent reductions in sulphate deposition in the regions examined. The observed trends seem to be ecologically important on decadal timescales, and support earlier contentions8-10 that declines in the deposition of base cations may have contributed to increased sensitivity of poorly buffered ecosystems.
C1 MICHIGAN STATE UNIV,DEPT ZOOL,HICKORY CORNERS,MI 49060.
   MICHIGAN STATE UNIV,DEPT GEOL SCI,HICKORY CORNERS,MI 49060.
   UNIV STOCKHOLM,DEPT METEOROL,S-10691 STOCKHOLM,SWEDEN.
   INST ECOSYST STUDIES,MILLBROOK,NY 12545.
   ROYAL NETHERLANDS METEOROL INST,DE BILT,NETHERLANDS.
   UNIV VIRGINIA,DEPT ENVIRONM SCI,CHARLOTTESVILLE,VA 22903.
C3 Michigan State University; Michigan State University; Stockholm University; Cary Institute of Ecosystem Studies; Royal Netherlands Meteorological Institute; University of Virginia
RP HEDIN, LO (corresponding author), MICHIGAN STATE UNIV,WK KELLOGG BIOL STN,HICKORY CORNERS,MI 49060, USA.
NR 37
TC 295
Z9 317
U1 0
U2 58
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 351
EP 354
DI 10.1038/367351a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000061
DA 2026-03-10
ER

PT J
AU CAHILL, L
   PRINS, B
   WEBER, M
   MCGAUGH, JL
AF CAHILL, L
   PRINS, B
   WEBER, M
   MCGAUGH, JL
TI BETA-ADRENERGIC ACTIVATION AND MEMORY FOR EMOTIONAL EVENTS
SO NATURE
LA English
DT Article
ID storage; involvement; blockers
AB SUBSTANTIAL evidence from animal studies suggests that enhanced memory associated,vith emotional arousal results from an activation of beta-adrenergic stress hormone systems during and after an emotional experience(1-3). To examine this implication in human subjects, we investigated the effect of the beta-adrenergic receptor antagonist propranolol hydrochloride on long-term memory for an emotionally arousing short story, or a closely matched but more emotionally neutral story. We report here that propranolol significantly impaired memory of the emotionally arousing story but did not affect memory of the emotionally neutral story. The impairing effect of propranolol on memory of the emotional story was not due either to reduced emotional responsiveness or to nonspecific sedative or attentional effects. The results support the hypothesis that enhanced memory associated with emotional experiences involves activation of the beta-adrenergic system.
C1 UNIV CALIF IRVINE,DEPT PSYCHOBIOL,IRVINE,CA 92717.
   VET AFFAIRS MED CTR,CTR HYPERTENS,LONG BEACH,CA 90822.
   UNIV CALIF IRVINE,DEPT MED,IRVINE,CA 92717.
C3 University of California System; University of California Irvine; US Department of Veterans Affairs; Veterans Health Administration (VHA); VA Long Beach Healthcare System; University of California System; University of California Irvine
RP CAHILL, L (corresponding author), UNIV CALIF IRVINE,CTR NEUROBIOL LEARNING & MEMORY,IRVINE,CA 92717, USA.
NR 18
TC 1001
Z9 1174
U1 2
U2 90
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 702
EP 704
DI 10.1038/371702a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300056
PM 7935815
DA 2026-03-10
ER

PT J
AU NAKAMURA, Y
   RUSSELL, SM
   MESS, SA
   FRIEDMANN, M
   ERDOS, M
   FRANCOIS, C
   JACQUES, Y
   ADELSTEIN, S
   LEONARD, WJ
AF NAKAMURA, Y
   RUSSELL, SM
   MESS, SA
   FRIEDMANN, M
   ERDOS, M
   FRANCOIS, C
   JACQUES, Y
   ADELSTEIN, S
   LEONARD, WJ
TI HETERODIMERIZATION OF THE IL-2 RECEPTOR BETA-CHAIN AND GAMMA-CHAIN CYTOPLASMIC DOMAINS IS REQUIRED FOR SIGNALING
SO NATURE
LA English
DT Article
ID human interleukin-2 receptor; cell growth-factor; functional component; distinct; expression; cloning; binding; gene; involvement; responses
AB THE interaction of interleukin-2 (IL-2) and IL-2 receptors critically regulates the T-cell immune response following antigen activation(1,2). IL-2 can signal through high or intermediate affinity receptors which contain IL-2R alpha (refs 3, 4) + beta (refs 5-8) + gamma (ref. 9) or beta + gamma chains, respectively. IL-2R gamma is a common gamma chain, gamma(c), also shared by the IL-7 (ref. 10) and IL-4 (refs 11, 12) receptors, which when mutated results in X-linked severe combined immunodeficiency(13). Using chimaeric receptor constructs together with monoclonal or bispecific antibodies we demonstrate here that IL-2 signalling requires ligand-induced extracellular-domain-mediated heterodimerization of the beta- and gamma(c)-chain cytoplasmic domains. Anti-IL-2R alpha monoclonal antibodies trigger proliferation of cells transfected with chimaeric constructs in which the extracellular domains of IL-2R beta and gamma(c), are replaced by that of IL-2R alpha. Other experiments using chimaeric constructs indicated that IL-2 binds monomerically and monovalently to IL-2R alpha and that the beta-transmembrane domain is not required for receptor chain interactions. Finally, we provide a method for mapping residues in the gamma(c) cytoplasmic domain even in cells that constitutively express gamma(c).
C1 NHLBI,PULM & MOLEC IMMUNOL SECT,BETHESDA,MD 20892.
   INST BIOL,INSERM,U211,F-44035 NANTES,FRANCE.
C3 National Institutes of Health (NIH) - USA; NIH National Heart Lung & Blood Institute (NHLBI); Institut National de la Sante et de la Recherche Medicale (Inserm)
NR 30
TC 314
Z9 348
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 330
EP 333
DI 10.1038/369330a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900053
PM 8183373
DA 2026-03-10
ER

PT J
AU ARCHER, D
   MAIERREIMER, E
AF ARCHER, D
   MAIERREIMER, E
TI EFFECT OF DEEP-SEA SEDIMENTARY CALCITE PRESERVATION ON ATMOSPHERIC CO2 CONCENTRATION
SO NATURE
LA English
DT Article
ID surface sediments; ice core; carbon-cycle; ocean; pacific; dissolution; atlantic; record
AB DURING the last glaciation, the atmospheric carbon dioxide concentration was about 30% less than the Holocene pre-industrial value1. Although this change is thought to originate in oceanic processes2, the mechanism is still unclear. On timescales of thousands of years, the pH of the ocean (and hence the atmospheric CO2 concentration) is determined by a steady-state balance between the supply rate of calcium carbonate to the ocean from terrestrial weathering, and the alteration and removal of carbonate by burial in sediments2-4 . Degradation of organic carbon in sediments promotes the dissolution of calcium carbonate in sedimentary pore water5,6, so that a change in the relative rates at which organic carbon and calcium carbonate are deposited on the sea floor should drive a compensating change in ocean pH. Here we use a model that combines ocean circulation, carbon cycling and other sedimentary processes to explore the relationship between deep-sea-sediment chemistry and atmospheric CO2 concentration. When we include organic-carbon-driven dissolution in our model, a 40% decrease in the calcite deposition rate is enough to decrease the atmospheric CO2 Concentration to the glacial value.
C1 COLUMBIA UNIV, PALISADES, NY 10964 USA.
   MAX PLANCK INST METEOROL, W-2000 HAMBURG 54, GERMANY.
C3 Columbia University; Max Planck Society
RP ARCHER, D (corresponding author), COLUMBIA UNIV, LAMONT DOHERTY EARTH OBSERV, PALISADES, NY 10964 USA.
NR 35
TC 454
Z9 490
U1 3
U2 113
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 260
EP 263
DI 10.1038/367260a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400052
DA 2026-03-10
ER

PT J
AU VANLEEUWEN, F
   SAMOS, CH
   NUSSE, R
AF VANLEEUWEN, F
   SAMOS, CH
   NUSSE, R
TI BIOLOGICAL-ACTIVITY OF SOLUBLE WINGLESS PROTEIN IN CULTURED DROSOPHILA IMAGINAL DISC CELLS
SO NATURE
LA English
DT Article
ID segment-polarity gene; encodes; expression; armadillo; product; homolog; int-1; plakoglobin; epidermis; embryos
AB THE phenotypes caused by mutations in Wnt genes suggest that their gene products are involved in cell-to-cell communication(1-6) Wnt genes indeed encode secreted molecules(7-10), but soluble active Wnt protein has not been found. We have developed a novel cell culture assay for the Drosophila Wnt gene wingless(11,12), using a Drosophila imaginal disc cell line (cl-8; ref. 13), and measured effects on the adherens junction protein armadillo(14,15), a known genetic target of wingless(16). Transfection of a temperature-sensitive wingless complementary DNA into cl-8 cells increases the levels of the armadillo protein. The wingless protein does not affect the rate of synthesis of armadillo, but leads to increased stability of an otherwise rapidly decaying armadillo protein. The wingless protein in the extracellular matrix and soluble medium from donor cells also increases the levels of armadillo protein. The protein in the medium acts fast and is inhibited by an antibody to wingless protein, demonstrating that Wnt products can act as soluble extracellular signalling molecules.
C1 STANFORD UNIV,SCH MED,HOWARD HUGHES MED INST,STANFORD,CA 94305.
   STANFORD UNIV,BECKMAN CTR,SCH MED,DEPT DEV BIOL,STANFORD,CA 94305.
C3 Howard Hughes Medical Institute; Stanford University; Stanford University
NR 27
TC 182
Z9 212
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 342
EP 344
DI 10.1038/368342a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500048
PM 8127369
DA 2026-03-10
ER

PT J
AU ESCOBAR, AL
   MONCK, JR
   FERNANDEZ, JM
   VERGARA, JL
AF ESCOBAR, AL
   MONCK, JR
   FERNANDEZ, JM
   VERGARA, JL
TI LOCALIZATION OF THE SITE OF CA2+ RELEASE AT THE LEVEL OF A SINGLE SARCOMERE IN SKELETAL-MUSCLE FIBERS
SO NATURE
LA English
DT Article
ID calcium transients; arsenazo-iii; sarcoplasmic-reticulum; contraction; fibers; resolution
AB THE development of mechanical force in skeletal muscle fibres is brought about by rapid increases in the intracellular calcium concentration (Ca2+ transients) which can be detected by optical methods1-7. Local stimulation experiments8 and ultrastructural evidence9,10 suggest that, at a microscopic level, these Ca2+ transients are generated by the release of Ca2+ ions from the terminal cisternae of the sarcoplasmic reticulum in response to the depolarization of the transverse tubules (t-tubules)11-14 . Nevertheless, to date, there is no functional information on the exact location at which Ca2+ release takes place. The present experiments were designed to obtain direct evidence about dynamic changes in localization and microscopic distribution of Ca2+ in a single sarcomere using two independent novel methodologies: confocal spot detection of Ca2+ transients15,16 and Ca2+ imaging with pulsed laser excitation17,18.
C1 UNIV CALIF LOS ANGELES,DEPT PHYSIOL,LOS ANGELES,CA 90024.
   MAYO CLIN & MAYO FDN,DEPT PHYSIOL & BIOPHYS,ROCHESTER,MN 55905.
C3 University of California System; University of California Los Angeles; Mayo Clinic
NR 30
TC 98
Z9 102
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 739
EP 741
DI 10.1038/367739a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100059
PM 8107869
DA 2026-03-10
ER

PT J
AU JIMENEZ, R
   FLEMING, GR
   KUMAR, PV
   MARONCELLI, M
AF JIMENEZ, R
   FLEMING, GR
   KUMAR, PV
   MARONCELLI, M
TI FEMTOSECOND SOLVATION DYNAMICS OF WATER
SO NATURE
LA English
DT Article
ID electron-transfer reactions; computer-simulation; molecular-dynamics; transfer rates; polar-solvent; transition; relaxation; liquids; pair
AB THE timescale of the response of solvent molecules to electronic rearrangement of solute molecules has a critical influence on the rates of chemical reactions in liquids(1-10). In particular, if the solvent cannot adapt quickly enough to this rearrangement as the reactants pass through the transition state, the evolving products may recross the free-energy barrier, reducing the reaction rate. Computer simulations have shown(11-18) that the response of a solvent to a change in solute charge distribution is strongly bimodal: there is an initial ultrafast response owing to inertial (mainly librational) motions of tbe solvent molecules, followed by a slow component owing to diffusive motions. Water seems to be by far the (fastest' solvent studied so far: simulations predict that well over half of the solvation response for atomic solutes is inertial, happening on a timescale of about 20 femtoseconds(12,13). The presence of this ultrafast component implies that solvent friction plays an important role in many aqueous charge-transfer processes(9,10,19-21). Experimental verification of this prediction has been lacking, however, in part because of the difficulty of obtaining sufficient time resolution. Here we present experimental measurements of the ultrafast solvation dynamics of a coumarin salt in water. When considered in conjunction with computer simulations, our results demonstrate that a solvent response on a timescale faster than 50 fs can dominate aqueous solvation dynamics.
C1 UNIV CHICAGO, JAMES FRANCK INST, CHICAGO, IL 60637 USA.
   PENN STATE UNIV, DEPT CHEM, STATE COLL, PA 16802 USA.
C3 University of Chicago; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
RP JIMENEZ, R (corresponding author), UNIV CHICAGO, DEPT CHEM, 5735 S ELLIS AVE, CHICAGO, IL 60637 USA.
NR 30
TC 1207
Z9 1280
U1 1
U2 211
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 471
EP 473
DI 10.1038/369471a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600052
DA 2026-03-10
ER

PT J
AU ARADYELLIN, R
   GREEN, BS
AF ARADYELLIN, R
   GREEN, BS
TI PHOTOCHEMICAL CLOSING AND OPENING OF THE GUEST-BINDING CAVITY OF CYCLODEXTRINS
SO NATURE
LA English
DT Article
AB CYCLODEXTRINS and modified derivatives can bind, and sometimes modifg the properties of, guest molecules in their torus-shaped cavities(1,2). They have also been used as the building blocks of molecular materials and devices(3). The propensity to bind and retain a guest is not easily predictable or controllable, however. There is currently much interest in the switching on and off of chemical(4) and biological(5) activity, particularly by photochemical means(6), as such functions will be required of molecular-scale devices. Here me report the controlled binding and release of guest molecules in cyclodextrins modified with substituents that can reversibly form bridging units across the cavity openings. Irradiation of percinnamoylated alpha- or beta-cyclodextrin in N-methylpyrrolidin-2-one (NMP) leads to the formation of intramolecular cyclobutane bridges which trap a bound NMP molecule. Irradiation at a different wavelength breaks open the cyclobutane rings and releases the guest.
C1 HEBREW UNIV JERUSALEM,FAC MED,SCH PHARM,DEPT PHARMACEUT CHEM,IL-91120 JERUSALEM,ISRAEL.
C3 Hebrew University of Jerusalem
NR 14
TC 24
Z9 24
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 320
EP 322
DI 10.1038/371320a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400048
DA 2026-03-10
ER

PT J
AU BRUNE, H
   ROMAINCZYK, C
   RODER, H
   KERN, K
AF BRUNE, H
   ROMAINCZYK, C
   RODER, H
   KERN, K
TI MECHANISM OF THE TRANSITION FROM FRACTAL TO DENDRITIC GROWTH OF SURFACE AGGREGATES
SO NATURE
LA English
DT Article
ID diffusion-limited aggregation; anisotropy; patterns; morphology
AB THE similarity of many patterns formed in non-equilibrium growth processes in physics, chemistry and biology is conspicuous, and many attempts have been made to discover common mechanisms underlying their formation(1). A central question is what causes some patterns to be dendritic (symmetrically branched, like snowflakes) and others fractal (randomly ramified). In general, the transition from fractal to dendritic growth is regarded as a manifestation of the predominance of anisotropy over random noise in the growth process. In electrochemical deposition, this transition is observed as the growth speed is varied(2,3). Here we report a crossover from fractal to dendritic growth in two dimensions on the microscopic scale. We use the scanning tunnelling microscope to study diffusion-limited aggregation of silver atoms on a Pt(111) surface. The transition occurs as the deposition flux is increased, and our observations suggest that the increasing importance of anisotropy of edge diffusion at higher flux is responsible for this crossover. We anticipate that a similar phenomenon may operate in three-dimensional crystal growth.
RP BRUNE, H (corresponding author), ECOLE POLYTECH FED LAUSANNE,INST PHYS EXPTL,CH-1015 LAUSANNE,SWITZERLAND.
NR 21
TC 247
Z9 258
U1 1
U2 136
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 469
EP 471
DI 10.1038/369469a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600051
DA 2026-03-10
ER

PT J
AU BASLER, K
   STRUHL, G
AF BASLER, K
   STRUHL, G
TI COMPARTMENT BOUNDARIES AND THE CONTROL OF DROSOPHILA LIMB PATTERN BY HEDGEHOG PROTEIN
SO NATURE
LA English
DT Article
ID segment-polarity gene; cell-cell communication; factor-beta family; engrailed expression; imaginal disks; posterior compartments; decapentaplegic gene; germ layers; melanogaster; wingless
AB Drosophila limbs are subdivided into anterior and posterior compartments which derive from adjacent cell populations founded early in development. Evidence is now provided that posterior cells organize growth and cell patterning in both compartments by secreting hedgehog protein and that hedgehog protein acts indirectly by inducing neighbouring anterior cells to secrete decapentaplegic or wingless protein.
C1 COLUMBIA UNIV, COLL PHYS & SURG, HOWARD HUGHES MED INST, NEW YORK, NY 10032 USA.
C3 Howard Hughes Medical Institute; Columbia University
RP BASLER, K (corresponding author), UNIV ZURICH, INST ZOOL, WINTERTHURERSTR 190, CH-8057 ZURICH, SWITZERLAND.
NR 72
TC 782
Z9 891
U1 0
U2 28
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 208
EP 214
DI 10.1038/368208a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000045
PM 8145818
DA 2026-03-10
ER

PT J
AU DOBRAN, F
   NERI, A
   TODESCO, M
AF DOBRAN, F
   NERI, A
   TODESCO, M
TI ASSESSING THE PYROCLASTIC FLOW HAZARD AT VESUVIUS
SO NATURE
LA English
DT Article
ID ad 79; eruptions; models
AB IN large eruptions, Vesuvius has generated catastrophic avalanches of tephra and hot gases, such as those that destroyed Pompei and Herculaneum in AD 79, and Torre del Greco and surrounding towns in 1631(1-12). These avalanches (pyroclastic surges and flows) are produced from collapses of the eruptive column, and can travel at > 100 m s-1, with temperatures exceeding 800-degrees-C. In 1944 Vesuvius ended its most recent cycle of activity, which had begun with the explosive eruption of 1631. Here we use numerical simulations to assess the hazards posed by the pyroclastic flows that are likely to accompany the onset of the next cycle of activity. We examine three different scales of eruption, and use vent conditions established by modelling magma ascent along the conduit13,14. Our results indicate that large- and medium-scale eruptions can produce complete destruction in the 7 km radius around the volcano (an area in which one million people live and work) in about 15 minutes or less, and that only small-scale eruptions can be arrested by the topographic relief of Monte Somma.
C1 IST NAZL GEOFIS,ROME,ITALY.
   UNIV PISA,DIPARTIMENTO SCI TERRA,I-56100 PISA,ITALY.
C3 Istituto Nazionale Geofisica e Vulcanologia (INGV); University of Pisa
RP DOBRAN, F (corresponding author), NYU,DEPT EARTH SYST SCI,NEW YORK,NY 10003, USA.
NR 28
TC 68
Z9 69
U1 0
U2 21
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 551
EP 554
DI 10.1038/367551a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300056
DA 2026-03-10
ER

PT J
AU TILMAN, D
   MAY, RM
   LEHMAN, CL
   NOWAK, MA
AF TILMAN, D
   MAY, RM
   LEHMAN, CL
   NOWAK, MA
TI HABITAT DESTRUCTION AND THE EXTINCTION DEBT
SO NATURE
LA English
DT Article
ID coexistence; competition; environment; disturbance; community
AB HABITAT destruction is the major cause of species extinctions(1-3) Dominant species often are considered to be free of this threat because they are abundant in the undisturbed fragments that remain after destruction. Here we describe a model that explains multispecies coexistence in patchy habitats(4) and which predicts that their abundance may be fleeting. Even moderate habitat destruction is predicted to cause time-delayed but deterministic extinction of the dominant competitor in remnant patches. Further species are predicted to become extinct, in order from the best to the poorest competitors, as habitat destruction increases. Moreover, the more fragmented a habitat already is, the greater is the number of extinctions caused by added destruction. Because such extinctions occur generations after fragmentation, they represent a debt-a future ecological cost of current habitat destruction.
C1 UNIV OXFORD,DEPT ZOOL,OXFORD OX1 3PS,ENGLAND.
C3 University of Oxford
RP TILMAN, D (corresponding author), UNIV MINNESOTA,DEPT ECOL EVOLUT & BEHAV,1987 UPPER BUFORD CIRCLE,ST PAUL,MN 55108, USA.
NR 30
TC 2083
Z9 2475
U1 22
U2 1003
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 65
EP 66
DI 10.1038/371065a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100051
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI BRIDGEHEAD OF SCIENCE REFORM
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 793
EP 793
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700026
DA 2026-03-10
ER

PT J
AU ATWOOD, JL
   KOUTSANTONIS, GA
   RASTON, CL
AF ATWOOD, JL
   KOUTSANTONIS, GA
   RASTON, CL
TI PURIFICATION OF C-60 AND C-70 BY SELECTIVE COMPLEXATION WITH CALIXARENES
SO NATURE
LA English
DT Article
ID water; fullerene
AB MOLECULAR complexation of fullerenes in host-guest complexes has the potential to afford efficient large-scale purification of fullerenes(1). This method would avoid the losses inherent in the chromatographic techniques currently in use, which arise from irreversible absorption on the stationary phase(2). Several host-guest interactions have been reported for C-60, including the formation of complexes with 1,4-hydroquinone(3,4), azacrown compounds(5), certain water-soluble macrocycles such as gamma-cyclodextrin(6-8), and complexation between C-60 and an iridium phosphine in which pendant groups attached to a phosphorus atom form a cradle for an adjacent C-60 molecule(9). Other relevant studies are the inclusion of C-60 into a microporous aluminophosphate(10) and the formation of a charge-transfer complex between C-60 and a thiafulvalene(11). Here we show that both C-60 and C-70 Will form discrete complexes with calixarenes, howl-shaped macrocycles with hydrophobic cavities. Complexation of p-Bu'-calix[8]arene with a mixture of the toluene extract of 'crude' fullerene soot, followed by a series of recrystallizations, affords >99.5% pure C-60. Our approach could lead to a substantial reduction in the cost of purifying C-60 and C-70.
C1 GRIFFITH UNIV,FAC SCI & TECHNOL,NATHAN,QLD 4111,AUSTRALIA.
   UNIV ALABAMA,DEPT CHEM,TUSCALOOSA,AL 35487.
C3 Griffith University; University of Alabama System; University of Alabama Tuscaloosa
NR 20
TC 601
Z9 641
U1 1
U2 130
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 229
EP 231
DI 10.1038/368229a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000050
DA 2026-03-10
ER

PT J
AU EMSLEY, J
   WHITE, HE
   OHARA, BP
   OLIVA, G
   SRINIVASAN, N
   TICKLE, IJ
   BLUNDELL, TL
   PEPYS, MB
   WOOD, SP
AF EMSLEY, J
   WHITE, HE
   OHARA, BP
   OLIVA, G
   SRINIVASAN, N
   TICKLE, IJ
   BLUNDELL, TL
   PEPYS, MB
   WOOD, SP
TI STRUCTURE OF PENTAMERIC HUMAN SERUM AMYLOID-P COMPONENT
SO NATURE
LA English
DT Article
ID c-reactive protein; cyclic 4,6-pyruvate acetal; binding-protein; concanavalin-a; sensitive site; calcium; resolution; galactose; specificity; refinement
AB The three-dimensional structure of pentameric human serum amyloid P component at high resolution, the first reported for a pentraxin, reveals that the tertiary fold is remarkably similar to that of the legume lectins. Carboxylate and phosphate compounds bind directly to two calcium ions; interactions with a carboxyethylidene ring are mediated by Asn 59 and Gln 148 ligands of the calcium ions. These X-ray results indicate the probable modes of binding of the biologically important ligands, DNA and amyloid fibrils.
C1 UNIV LONDON BIRKBECK COLL,MOLEC BIOL LAB,LONDON WC1E 7HX,ENGLAND.
   UNIV LONDON BIRKBECK COLL,DEPT CRYSTALLOG,ICRF,STRUCT MOLEC BIOL UNIT,LONDON WC1E 7HX,ENGLAND.
   HAMMERSMITH HOSP,ROYAL POSTGRAD MED SCH,IMMUNOL MED UNIT,LONDON W12 0NN,ENGLAND.
C3 University of London; Birkbeck University London; University of London; Birkbeck University London; Imperial College London
NR 42
TC 434
Z9 488
U1 1
U2 55
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 338
EP 345
DI 10.1038/367338a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000058
PM 8114934
DA 2026-03-10
ER

PT J
AU SUKI, B
   BARABASI, AL
   HANTOS, Z
   PETAK, F
   STANLEY, HE
AF SUKI, B
   BARABASI, AL
   HANTOS, Z
   PETAK, F
   STANLEY, HE
TI AVALANCHES AND POWER-LAW BEHAVIOR IN LUNG-INFLATION
SO NATURE
LA English
DT Article
ID airway-closure; model
AB WHEN lungs are emptied during exhalation, peripheral airways close up1. For people with lung disease, they may not reopen for a significant portion of inhalation, impairing gas exchange2,3. A knowledge of the mechanisms that govern reinflation of collapsed regions of lungs is therefore central to the development of ventilation strategies for combating respiratory problems. Here we report measurements of the terminal airway resistance, R(t), during the opening of isolated dog lungs. When inflated by a constant flow, R(t) decreases in discrete jumps. We find that the probability distribution of the sizes of the jumps and of the time intervals between them exhibit power-law behaviour over two decades. We develop a model of the inflation process in which 'avalanches' of airway openings are seen-with power-law distributions of both the size of avalanches and the time intervals between them-which agree quantitatively with those seen experimentally, and are reminiscent of the power-law behaviour observed for self-organized critical systems4. Thus power-law distributions, arising from avalanches associated with threshold phenomena propagating down a branching tree structure, appear to govern the recruitment of terminal airspaces.
C1 BOSTON UNIV,CTR POLYMER STUDIES,BOSTON,MA 02215.
   BOSTON UNIV,DEPT PHYS,BOSTON,MA 02215.
   ALBERT SZENT GYORGYI MED UNIV,DEPT MED INFORMAT,SZEGED,HUNGARY.
   ALBERT SZENT GYORGY MED UNIV,DEPT EXPTL SURG,SZEGED,HUNGARY.
C3 Boston University; Boston University; Szeged University; Szeged University
RP SUKI, B (corresponding author), BOSTON UNIV,DEPT BIOMED ENGN,RESP RES LAB,BOSTON,MA 02215, USA.
NR 16
TC 232
Z9 248
U1 0
U2 21
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 615
EP 618
DI 10.1038/368615a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200054
PM 8145846
DA 2026-03-10
ER

PT J
AU KAUFMAN, YJ
   TANRE, D
AF KAUFMAN, YJ
   TANRE, D
TI EFFECT OF VARIATIONS IN SUPERSATURATION ON THE FORMATION OF CLOUD CONDENSATION NUCLEI
SO NATURE
LA English
DT Article
ID aerosol; chemistry; climate; ocean
AB SULPHATE aerosols can act as nuclei for cloud formation, thereby cooling the climate by increasing the Earth's albedo(1-5): however the magnitude of this effect is very uncertain(3,6). Recently, Langner et al.(7) calculated that at most 6% of the anthropogenic sulphur emission forms new particles, while 44% adds mass to existing sulphate particles activated in clouds. It was therefore suggested(7,8) that previous studies(1,2,9) had overestimated the effect of sulphate aerosols on climate. Although it has been proposed that sub-CCN-size particles can grow to CCN-size in clouds(7,10), this was thought to require the large supersaturations present in cumuliform clouds, rather than the smaller values characteristic of marine stratiform clouds, which are most important for radiative forcing. Here we show that natural variability of even low average supersaturations allows particles as small as 0.015 mu m to grow to become CCN. This process can quadruple the CCN concentration and significantly increase the corresponding aerosol effect on climate.
C1 UNIV LILLE 1,OPT ATMOSPHER LAB,F-59655 VILLENEUVE DASCQ,FRANCE.
C3 Universite de Lille
RP KAUFMAN, YJ (corresponding author), NASA,GODDARD SPACE FLIGHT CTR,CODE 913,GREENBELT,MD 20771, USA.
NR 26
TC 64
Z9 72
U1 0
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 45
EP 48
DI 10.1038/369045a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000047
DA 2026-03-10
ER

PT J
AU WEIDENSCHILLING, SJ
AF WEIDENSCHILLING, SJ
TI ORIGIN OF COMETARY NUCLEI AS RUBBLE PILES
SO NATURE
LA English
DT Article
ID outbursts; system
AB COMETS are extremely fragile objects. Observations of outbursts and splitting have inspired suggestions that their nuclei are 'rubble piles', consisting of components that are weakly bonded, perhaps held together by mutual gravity(1,2). This structure was confirmed in spectacular fashion by comet Shoemaker-Levy 9, which disintegrated into about 20 fragments after passing near Jupiter; the tidal stresses induced by the planet were only of the order of 10(-4) bar (ref. 3). Attempts to explain the formation of comets in the outer Solar System have emphasized either collisional coagulation(1) or gravitational collapse of a layer of dust particles(4,5). Here I argue that the observed sized and structure of comet nuclei are better explained by a two-stage process, involving elements of both models-collisional coagulation in the solar nebula, followed by gravitational instability of a layer of macroscopic bodies.
RP WEIDENSCHILLING, SJ (corresponding author), PLANETARY SCI INST,620 N 6TH AVE,TUCSON,AZ 85705, USA.
NR 14
TC 52
Z9 52
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 721
EP 723
DI 10.1038/368721a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300051
DA 2026-03-10
ER

PT J
AU GURDON, JB
   HARGER, P
   MITCHELL, A
   LEMAIRE, P
AF GURDON, JB
   HARGER, P
   MITCHELL, A
   LEMAIRE, P
TI ACTIVIN SIGNALING AND RESPONSE TO A MORPHOGEN GRADIENT
SO NATURE
LA English
DT Article
ID drosophila embryo; xenopus-laevis; mesoderm induction; axial mesoderm; retinoic acid; protein; homolog; pattern; cells; thresholds
AB Using combinations of amphibian embryo tissues, it is shown that the selection of genes expressed by a cell is determined by its distance from a source of activin, a peptide growth factor contained in vegetal cells and able to induce other cells to form mesoderm. This long-range signal spreads over at least 10 cell diameters In a few hours. It does so by passive diffusion, because It can by-pass cells that do not themselves respond to the signal nor synthesize protein. These results provide direct support for the operation of a morphogen concentration gradient In vertebrate development.
C1 UNIV CAMBRIDGE,DEPT ZOOL,CAMBRIDGE CB2 3EJ,ENGLAND.
C3 University of Cambridge
RP GURDON, JB (corresponding author), WELLCOME CRC INST,TENNIS COURT RD,CAMBRIDGE CB2 1QR,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 47
TC 313
Z9 353
U1 0
U2 24
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 487
EP 492
DI 10.1038/371487a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900046
PM 7935761
DA 2026-03-10
ER

PT J
AU LAU, LL
   JAMIESON, BD
   SOMASUNDARAM, T
   AHMED, R
AF LAU, LL
   JAMIESON, BD
   SOMASUNDARAM, T
   AHMED, R
TI CYTOTOXIC T-CELL MEMORY WITHOUT ANTIGEN
SO NATURE
LA English
DT Article
ID lymphocytic choriomeningitis virus; persisting antigen; selection
AB Memory is a hallmark of the immune system and ever since its recognition there has been considerable interest in understanding how immunity is maintained(1-5). The current model is that long-term memory is dependent on persistent antigenic stimulation(6-11). We report here results that challenge this view and provide evidence that antigen is not essential for the maintenance of CD8(+) T-cell memory. We show that memory CD8(+) cytotoxic T lymphocytes persist indefinitely in the absence of priming antigen, retain the memory phenotype (CD44(hi)), and provide protection against virus challenge. These findings suggest a re-evaluation of our current thinking on mechanisms involved in maintaining immunity and have implications towards designing effective vaccination strategies.
C1 UNIV CALIF LOS ANGELES, SCH MED, DEPT MICROBIOL & IMMUNOL, LOS ANGELES, CA 90024 USA.
C3 University of California System; University of California Los Angeles; University of California Los Angeles Medical Center; David Geffen School of Medicine at UCLA
NR 21
TC 593
Z9 680
U1 0
U2 10
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 648
EP 652
DI 10.1038/369648a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900055
PM 7516038
DA 2026-03-10
ER

PT J
AU RICHARDS, DA
   SMART, PL
   EDWARDS, RL
AF RICHARDS, DA
   SMART, PL
   EDWARDS, RL
TI MAXIMUM SEA LEVELS FOR THE LAST GLACIAL PERIOD FROM U-SERIES AGES OF SUBMERGED SPELEOTHEMS
SO NATURE
LA English
DT Article
ID papua-new-guinea; oxygen isotopes; huon-peninsula; th ages; record; temperature; corals; barbados; climate; hole
AB PLEISTOCENE sea Levels reflect changes in the surface distribution of land, sea and ice, which in turn significantly influence the Earth's climate1. The most complete record of sea levels for the last glacial cycle has come from raised coral reef terraces of the Huon Peninsula, Papua New Guinea2-4, but interpretation of this record is hampered by relatively large age uncertainties and the possibility of variation in the rate of tectonic uplift. Subaerial speleothems (stalagmites, stalactites and flowstones) from submerged caves in tectonically stable areas provide an alternative source of data5-8, as their growth stops when rising sea levels flood the caves. Previous studies of speleothems have been limited by dating precision5,6 and sample availability5-7. Here we present high-precision thermal-ionization mass-spectrometric Th-232 ages9-11 for a comprehensive suite of speleothem samples from the Bahamas. Our results provide a record of maximum elevation of sea levels for the period from 80 to 10 kyr before the present, for much of which sea levels are poorly known. We also find that regional palaeoclimatic change can be an important factor in the termination of speleothem growth.
C1 UNIV MINNESOTA, DEPT GEOL & GEOPHYS, MINNESOTA ISOTOPE LAB, MINNEAPOLIS, MN 55455 USA.
C3 University of Minnesota System; University of Minnesota Twin Cities
RP RICHARDS, DA (corresponding author), UNIV BRISTOL, DEPT GEOG, BRISTOL BS8 1SS, ENGLAND.
NR 38
TC 96
Z9 105
U1 0
U2 27
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 357
EP 360
DI 10.1038/367357a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000063
DA 2026-03-10
ER

PT J
AU PARKES, RJ
   CRAGG, BA
   BALE, SJ
   GETLIFF, JM
   GOODMAN, K
   ROCHELLE, PA
   FRY, JC
   WEIGHTMAN, AJ
   HARVEY, SM
AF PARKES, RJ
   CRAGG, BA
   BALE, SJ
   GETLIFF, JM
   GOODMAN, K
   ROCHELLE, PA
   FRY, JC
   WEIGHTMAN, AJ
   HARVEY, SM
TI DEEP BACTERIAL BIOSPHERE IN PACIFIC-OCEAN SEDIMENTS
SO NATURE
LA English
DT Article
AB ALTHOUGH around 70% of the Earth's surface is marine, little is known about the microbiology of underlying sediments, which can be more than a kilometre deep(1). Selective degradation of organic matter within sediments over geological time profoundly affects the chemical composition of the ocean and atmosphere(2). Microbial processes have a fundamental role in surface sediments(3,4), but despite geochemical evidence(5), their significance in deeper sediments has not been established(6). Here we report the discovery of viable sediment bacterial populations at five Pacific Ocean sites to depths >500 m. Bacterial distributions and activities are commensurate,vith geochemical changes. Bacterial profiles with depth are remarkably consistent, and deviations can be linked to specific environmental factors. The rate of decline in these populations indicates that bacteria are present to even greater depths. These bacteria, some of which are unique, must have a profound effect on deep-sediment diagenetic processes, and their presence considerably extends the biosphere.
C1 UNIV WALES COLL CARDIFF, SCH PURE & APPL BIOL, CARDIFF CF1 3TL, WALES.
   DUNSTAFFNAGE MARINE RES LAB, OBAN PA34 4AD, ARGYLL, SCOTLAND.
C3 Cardiff University
RP PARKES, RJ (corresponding author), UNIV BRISTOL, DEPT GEOL, BRISTOL BS8 1RJ, ENGLAND.
NR 30
TC 486
Z9 560
U1 0
U2 99
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 410
EP 413
DI 10.1038/371410a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500040
DA 2026-03-10
ER

PT J
AU CANHAM, LT
   CULLIS, AG
   PICKERING, C
   DOSSER, OD
   COX, TI
   LYNCH, TP
AF CANHAM, LT
   CULLIS, AG
   PICKERING, C
   DOSSER, OD
   COX, TI
   LYNCH, TP
TI LUMINESCENT ANODIZED SILICON AEROCRYSTAL NETWORKS PREPARED BY SUPERCRITICAL DRYING
SO NATURE
LA English
DT Article
ID porous silicon; temperature
AB THE preparation of highly porous materials by sol-gel processing followed by supercritical drying was pioneered by Kistler in 1931(1). These materials, called aerogels and comprising a void fraction of more than 90%, are currently a focus of technological interest(2). Here we show that supercritical drying can be used to prepare highly porous silicon, a material of particular interest because of its luminescent properties(3). Porous silicon is prepared conventionally by electrochemical etching, but using supercritical fluid extraction allows us to obtain porosities that would otherwise lead to collapse of the network during drying. Electron microscopy reveals that our materials have a crystalline, columnar structure, and gravimetric and ellipsometric analysis indicates that the porosity exceeds 95%. Our silicon aerocrystals exhibit strong photoluminescence. We predict that supercritical drying should greatly improve those properties of porous silicon films that are critical for optoelectronic applications.
C1 BP INT LTD,CTR GRP RES & ENGN,SUNBURY TW16 7LL,SURREY,ENGLAND.
C3 BP
RP CANHAM, LT (corresponding author), DEF RES AGCY MALVERN,ST ANDREWS RD,MALVERN WR14 3PS,WORCS,ENGLAND.
NR 15
TC 174
Z9 188
U1 1
U2 36
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 133
EP 135
DI 10.1038/368133a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000061
DA 2026-03-10
ER

PT J
AU PARRILLA, G
   LAVIN, A
   BRYDEN, H
   GARCIA, M
   MILLARD, R
AF PARRILLA, G
   LAVIN, A
   BRYDEN, H
   GARCIA, M
   MILLARD, R
TI RISING TEMPERATURES IN THE SUBTROPICAL NORTH-ATLANTIC OCEAN OVER THE PAST 35 YEARS
SO NATURE
LA English
DT Article
ID carbon-dioxide; model
AB As an oceanographic contribution to the quincentennial celebrations of Columbus's voyage of discovery in 1492, a collaborative expedition was carried out in July-August 1992 to make a transatlantic, deep-ocean hydrographic section along Columbus's route at 24 degrees N. The 24 degrees N section is of interest for studies of climate change because it has been surveyed twice before, during the International Geophysical Year of 1957(1) and during 1981(2) and hence represents one of the best known of all oceanographic sections. Here we use the temperatures from all three surveys to show that the waters between 800 and 2,500 m depth have consistently warmed over the past 35 years and that the warming since 1957 is remarkably uniform across the east-west extent of the North Atlantic. The maximum warming, found at 1,100 m depth, is occurring at a rate of 1 degrees C per century. This trend is broadly consistent with model predictions of climate change due to increases in atmospheric CO2 concentration(3,4), but the observed warming occurs in the interior ocean, in contrast to the surface-warming predicted by the models. The observed patterns of decadal-scale changes in ocean temperature are thus powerful signatures that can help us to understand the nature and causes of climate change.
C1 INST ESPANOL OCEANOG,E-39080 SANTANDER,SPAIN.
   JAMES RENNELL CTR OCEAN CIRCULATION,CHILWORTH RES CTR,SOUTHAMPTON SO1 7NS,HANTS,ENGLAND.
   WOODS HOLE OCEANOG INST,DEPT PHYS OCEANOG,WOODS HOLE,MA 02543.
C3 Spanish Institute of Oceanography; University of Southampton; NERC National Oceanography Centre; Woods Hole Oceanographic Institution
RP PARRILLA, G (corresponding author), INST ESPANOL OCEANOG,CORAZON MARIA 8,E-28002 MADRID,SPAIN.
NR 21
TC 80
Z9 81
U1 0
U2 161
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 48
EP 51
DI 10.1038/369048a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000048
DA 2026-03-10
ER

PT J
AU UYEDA, TQP
   RUPPEL, KM
   SPUDICH, JA
AF UYEDA, TQP
   RUPPEL, KM
   SPUDICH, JA
TI ENZYMATIC-ACTIVITIES CORRELATE WITH CHIMERIC SUBSTITUTIONS AT THE ACTIN-BINDING FACE OF MYOSIN
SO NATURE
LA English
DT Article
ID heavy-chain gene; adenosine-triphosphatase; subfragment-1; meromyosin; actomyosin; site; atp; disruption; hydrolysis; mechanism
AB MYOSINS are a functionally divergent group of mechanochemical enzymes involved in various motile activities in cells1. Despite a high degree of conservation in the amino-acid sequence of the 130K motor domain2,3 (head region) of the molecule, there are large differences in the enzymatic and motile activities (Tables 1 and 2) of myosins from diverse species and cell types. However, the degree of conservation is not uniform throughout the head sequence4; therefore, one reasonable hypothesis is that the functional differences between myosins derive from the poorly conserved areas. The most prominent divergent region occurs at the 50K/20K junction, a region of the molecule sensitive to proteolytic digestion5 and a binding site for actin6-12. We have now constructed chimaeras of this region of myosin by substituting the 9-amino-acid Dictyostelium junction region with those from myosins from other species and find that the actin-activated ATPase correlates well with the activity of the myosin from which the junction region was derived. Our results suggest that this region, likely to be part of the myosin head that interacts directly with actin10,13,14, is important in deter mining the enzymatic activity of myosin.
C1 STANFORD UNIV,MED CTR,SCH MED,DEPT BIOCHEM,STANFORD,CA 94305.
   STANFORD UNIV,MED CTR,SCH MED,DEPT DEV BIOL,STANFORD,CA 94305.
C3 Stanford University; Stanford University
NR 30
TC 189
Z9 216
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 567
EP 569
DI 10.1038/368567a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500061
PM 8139694
DA 2026-03-10
ER

PT J
AU PUROHIT, P
   STERN, S
AF PUROHIT, P
   STERN, S
TI INTERACTIONS OF A SMALL RNA WITH ANTIBIOTIC AND RNA LIGANDS OF THE 30S SUBUNIT
SO NATURE
LA English
DT Article
ID 16s ribosomal-rna; i intron rna; chemical probes; p-site; binding; nucleotides; inhibition
AB IT is now generally accepted that 16S and 23S ribosomal RNA play important roles in the decoding and peptidyl transferase activities of ribosomes(1,2). Despite their complex structures and numerous associated proteins it is possible that small domains of these rRNAs can fold and function autonomously, particularly those that appear devoid of protein interactions(3). One candidate for such a domain is the decoding region, located near the 3' end of 16S rRNA (Fig. 1a, b). Consistent with this hypothesis, aminoglycoside antibiotics that interact with the decoding region in 30S subunits interact with other RNAs in the absence of proteins(4-7). In addition, certain activities of self-splicing introns, at least superficially, resemble translational decoding(8,9). We report here that an oligoribonucleotide analogue of the decoding region interacts with both antibiotic and RNA ligands of the 30S subunit in a manner that correlates with normal subunit function. The activities of the decoding region analogue suggest that the intimidating structural complexity of the ribosome can be, to some degree, circumvented.
RP PUROHIT, P (corresponding author), UNIV MASSACHUSETTS, SCH MED, PROGRAM MOLEC MED, 373 PLANTAT ST, WORCESTER, MA 01605 USA.
NR 26
TC 262
Z9 306
U1 1
U2 5
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 659
EP 662
DI 10.1038/370659a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000053
PM 8065453
DA 2026-03-10
ER

PT J
AU GRAVES, BJ
   CROWTHER, RL
   CHANDRAN, C
   RUMBERGER, JM
   LI, S
   HUANG, KS
   PRESKY, DH
   FAMILLETTI, PC
   WOLITZKY, BA
   BURNS, DK
AF GRAVES, BJ
   CROWTHER, RL
   CHANDRAN, C
   RUMBERGER, JM
   LI, S
   HUANG, KS
   PRESKY, DH
   FAMILLETTI, PC
   WOLITZKY, BA
   BURNS, DK
TI INSIGHT INTO E-SELECTIN LIGAND INTERACTION FROM THE CRYSTAL-STRUCTURE AND MUTAGENESIS OF THE LEC EGF DOMAINS
SO NATURE
LA English
DT Article
ID leukocyte-adhesion molecule-1; growth factor-alpha; mannose-binding protein; node homing receptor; carbohydrate-recognition; evolutionary conservation; functional interactions; nmr-spectroscopy; cell-adhesion; p-selectin
AB The three-dimensional structure of the ligand-binding region of human E-selectin has been determined at 2.0 angstrom resolution. The structure reveals limited contact between the two domains and a coordination of Ca2+ not predicted from other C-type lectins. Structure/function analysis indicates a defined region and specific amino-acid side chains that may be involved in ligand binding. These features of the E-selectin/ligand interaction have important implications for understanding the recruitment of leukocytes to sites of inflammation.
RP GRAVES, BJ (corresponding author), HOFFMANN LA ROCHE INC,ROCHE RES CTR,NUTLEY,NJ 07110, USA.
NR 52
TC 409
Z9 438
U1 1
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 532
EP 538
DI 10.1038/367532a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300050
PM 7509040
DA 2026-03-10
ER

PT J
AU ASPHAUG, E
   BENZ, W
AF ASPHAUG, E
   BENZ, W
TI DENSITY OF COMET SHOEMAKER-LEVY-9 DEDUCED BY MODELING BREAKUP OF THE PARENT RUBBLE-PILE
SO NATURE
LA English
DT Article
ID tidal disruption; body
AB FOR a week beginning 16 July 1994, fragments of comet Shoemaker-Levy 9 win collide with Jupiter each day. Although the fragments are probably smaller than originally estimated(1), the impacts may nevertheless have observable consequences that will provide valuable insight into the properties of comets and the dynamics of planetary atmospheres. Interpretation of these observations will depend sensitively on parameters such as the mass, density and overall structure of the fragments. To deduce some of these parameters, we have simulated the event that created the fragments-the passage of the parent comet through the tidal field of Jupiter in 1992. Modelling the comet as a strengthless aggregate consisting of a large number of grains, we find that the tidally disrupted body condenses rapidly into clumps, driven by their self-gravity. Formation of a fragment chain resembling Shoemaker-Levy 9 occurs for a narrow range of the simulated comet's bulk density, 0.3-0.7 g cm(-3). A chain of similar to 20 similar-sized fragments matching observations is obtained for a non-rotating parent comet of 1.5 km diameter and bulk density 0.5 g cm(-3), suggesting that the clusters will each liberate similar to 10(27) erg on impact. A slightly larger initial density leads to significant mass variation among the clusters and the possibility of a few similar to 10(28)-erg events.
C1 UNIV ARIZONA,STEWARD OBSERV,TUCSON,AZ 85721.
   UNIV ARIZONA,LUNAR & PLANETARY LAB,TUCSON,AZ 85721.
C3 University of Arizona; University of Arizona
RP ASPHAUG, E (corresponding author), NASA,AMES RES CTR 2453,MOFFETT FIELD,CA 94035, USA.
NR 14
TC 148
Z9 157
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 120
EP 124
DI 10.1038/370120a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400049
DA 2026-03-10
ER

PT J
AU RODRIGUEZVICIANA, P
   WARNE, PH
   DHAND, R
   VANHAESEBROECK, B
   GOUT, I
   FRY, MJ
   WATERFIELD, MD
   DOWNWARD, J
AF RODRIGUEZVICIANA, P
   WARNE, PH
   DHAND, R
   VANHAESEBROECK, B
   GOUT, I
   FRY, MJ
   WATERFIELD, MD
   DOWNWARD, J
TI PHOSPHATIDYLINOSITOL-3-OH KINASE AS A DIRECT TARGET OF RAS
SO NATURE
LA English
DT Article
ID gtpase-activating protein; growth-factor receptor; different signaling pathways; sh3 domain; 3-kinase; bind; association; expression; 3'-kinase; complex
AB Ras (p21(ras)) interacts directly with the catalytic subunit of phosphatidylinositol-3-OH kinase in a GTP-dependent manner through the Ras effector site. In vivo, dominant negative Ras mutant N17 inhibits growth factor induced production of 3' phosphorylated phosphoinositides in PC12 cells, and transfection of Ras, but not Raf, into COS cells results in a large elevation in the level of these lipids. Therefore Ras can probably regulate phosphatidylinositol-3-OH kinase, providing a point of divergence in signalling pathways downstream of Ras.
C1 IMPERIAL CANC RES FUND,LONDON WC2A 3PX,ENGLAND.
   LUDWIG INST CANC RES,LONDON W1P 8BT,ENGLAND.
   UNIV LONDON UNIV COLL,DEPT BIOCHEM & MOLEC BIOL,LONDON WC1E 6BT,ENGLAND.
C3 Cancer Research UK; Ludwig Institute for Cancer Research; University of London; University College London
NR 36
TC 1684
Z9 1985
U1 0
U2 46
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 527
EP 532
DI 10.1038/370527a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700046
PM 8052307
DA 2026-03-10
ER

PT J
AU SCHLIEWEN, UK
   TAUTZ, D
   PAABO, S
AF SCHLIEWEN, UK
   TAUTZ, D
   PAABO, S
TI SYMPATRIC SPECIATION SUGGESTED BY MONOPHYLY OF CRATER LAKE CICHLIDS
SO NATURE
LA English
DT Article
ID mitochondrial-dna sequences; reproductive isolation; evolution; fishes; malawi; animals; africa; pisces
AB THE existence of sympatric speciation-that populations diverge into species in the absence of physical or ecological barriers-is controversial1-6. The East African Great Lakes harbour hundreds of cichlid species representing only a few monophyletic lineages7,8, although palaeolimnological evidence9-11 and local restrictions on species distribution12 suggest that speciation in these lakes could have been allopatric13,14. The case for sympatry in restricted areas of Lakes Malawi and Tanganyika is stronger15-17 but not unassailable. A better case might be made for cichlid species flocks in small, ecologically monotonous crater lakes. Here we present a mitochondrial DNA analysis of cichlid species flocks endemic to two such lakes in Cameroon. The results suggest that the flocks in each lake are monophyletic: the implication being that each lake was colonized once only, the size and shape of each lake being such that subsequent diversification would have been sympatric.
C1 MAX PLANCK INST VERHALTENSPHYSIOL,D-82319 SEEWIESEN,GERMANY.
C3 Max Planck Society
RP SCHLIEWEN, UK (corresponding author), INST ZOOL,POSTFACH 202136,D-80021 MUNICH,GERMANY.
NR 42
TC 353
Z9 395
U1 4
U2 113
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 629
EP 632
DI 10.1038/368629a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200059
PM 8145848
DA 2026-03-10
ER

PT J
AU MANSER, E
   LEUNG, T
   SALIHUDDIN, H
   ZHAO, ZS
   LIM, L
AF MANSER, E
   LEUNG, T
   SALIHUDDIN, H
   ZHAO, ZS
   LIM, L
TI A BRAIN SERINE THREONINE PROTEIN-KINASE ACTIVATED BY CDC42 AND RAC1
SO NATURE
LA English
DT Article
ID gtp-binding-protein; gdp dissociation inhibitor; focal adhesions; ras proteins; r-ras; rho; identification; expression; homolog; phosphorylation
AB A new brain serine/threonine protein kinase may be a target for the p21ras-related proteins Cdc42 and Rac1. The kinase sequence is related to that of the yeast protein STE20, implicated in pheromone-response pathways. The kinase complexes specifically with activated (GTP-bound) p21, inhibiting p21 GTPase activity and leading to kinase autophosphorylation and activation. Autophosphorylated kinase has a decreased affinity for Cdc42/Rac, freeing the p21 for further stimulatory activities or downregulation by GTPase-activating proteins. This bimolecular interaction provides a model for studying p21 regulation of mammalian phosphorylation signalling pathways.
C1 INST NEUROL,LONDON WC1N 1PJ,ENGLAND.
C3 University of London; University College London
RP MANSER, E (corresponding author), NATL UNIV SINGAPORE,INST MOLEC & CELL BIOL,GLAXO IMCB GRP,KENT RIDGE,SINGAPORE 0511,SINGAPORE.
NR 49
TC 1379
Z9 1562
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 40
EP 46
DI 10.1038/367040a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500051
PM 8107774
DA 2026-03-10
ER

PT J
AU FENTON, WA
   KASHI, Y
   FURTAK, K
   HORWICH, AL
AF FENTON, WA
   KASHI, Y
   FURTAK, K
   HORWICH, AL
TI RESIDUES IN CHAPERONIN GROEL REQUIRED FOR POLYPEPTIDE BINDING AND RELEASE
SO NATURE
LA English
DT Article
ID molecular chaperone; atp hydrolysis; proteins; cooperativity; cell
AB CHAPERONINS are king-shaped protein complexes that are essential in the cell, mediating ATP-dependent polypeptide folding in a variety of compartments(1-3). Recent studies suggest that they function through multiple rounds of binding and release of non-native proteins: with each round of ATP-driven release into the bulk solution, a substrate protein kinetically partitions between folding to the native state or rebinding to another chaperonin molecule(4-6). To gain further insight into the mechanism of polypeptide binding and release by the chaperonin GroEL from Escherichia coli, we have undertaken a mutational analysis that relates the functional properties of GroEL to its crystal structure(7). Our functional tests identify a putative polypeptide-binding site on the inside surface of the apical domain, facing the central channel, consisting of hydrophobic residues. These same residues are essential for binding of the co-chaperonin GroES, which is required for productive polypeptide release. A highly conserved residue, Asp 87, positioned within a putative nucleotide-binding pocket in the top of the equatorial domain, is essential for ATP hydrolysis and polypeptide release.
C1 YALE UNIV,SCH MED,BOYER CTR,HOWARD HUGHES MED INST,NEW HAVEN,CT 06510.
   YALE UNIV,SCH MED,BOYER CTR,DEPT GENET,NEW HAVEN,CT 06510.
C3 Howard Hughes Medical Institute; Yale University; Yale University
NR 22
TC 589
Z9 647
U1 0
U2 47
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 614
EP 619
DI 10.1038/371614a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900055
PM 7935796
DA 2026-03-10
ER

PT J
AU CHOO, Y
   SANCHEZGARCIA, I
   KLUG, A
AF CHOO, Y
   SANCHEZGARCIA, I
   KLUG, A
TI IN-VIVO REPRESSION BY A SITE-SPECIFIC DNA-BINDING PROTEIN DESIGNED AGAINST AN ONCOGENIC SEQUENCE
SO NATURE
LA English
DT Article
ID chronic myelogenous leukemia; acute lymphoblastic-leukemia; transcription factor-iiia; c-abl protein; mammalian-cells; philadelphia-chromosome; domains; expression; genes; bcr
AB A DNA-binding peptide comprising three zinc-fingers has been engineered to bind specifically to a unique nine-base-pair region of a BCR-ABL fusion oncogene in preference to the parent genomic sequences. Binding to the target oncogene in chromosomal DNA is possible In transformed cells in culture, and results in blockage of transcription. Consequently, murine cells rendered independent of growth factors by the action of the oncogene revert to factor dependence upon transient transfection with a vector expressing the peptide.
RP CHOO, Y (corresponding author), MRC,MOLEC BIOL LAB,HILLS RD,CAMBRIDGE CB2 2QH,ENGLAND.
NR 37
TC 242
Z9 337
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 642
EP 645
DI 10.1038/372642a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700076
PM 7990954
DA 2026-03-10
ER

PT J
AU KOVACS, I
   JULESZ, B
AF KOVACS, I
   JULESZ, B
TI PERCEPTUAL SENSITIVITY MAPS WITHIN GLOBALLY DEFINED VISUAL SHAPES
SO NATURE
LA English
DT Article
ID channels
AB AN unsolved problem of biology is the processing of global shape in natural vision. The known processes of early vision are spatially restricted (or local) operations, and little is known about their interactions in organizing the visual image into functionally coherent (or global) objects. Here we introduce a human psychophysical method which allows us to measure the effect of perceptual organization on the activity pattern of local visual detectors, We map differential contrast sensitivity for a target across regions enclosed by a boundary. We show that local contrast sensitivity is enhanced within the boundary even for large distances between the boundary and the target. Furthermore, the locations of maximal sensitivity enhancement in the sensitivity maps are determined by global shape properties. Our data support a class of models which describe shapes by the means of a medial axis transformation(1-3), implying that the visual system extracts 'skeletons' as an intermediate-lever representation of objects. The skeletal representation offers a structurally simplified shape description which can be used for higher-level operations and for coding into memory.
RP KOVACS, I (corresponding author), RUTGERS STATE UNIV,VIS RES LAB,BUSCH CAMPUS,PSYCHOL BLDG,PISCATAWAY,NJ 08854, USA.
NR 17
TC 181
Z9 193
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 644
EP 646
DI 10.1038/370644a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000048
PM 8065449
DA 2026-03-10
ER

PT J
AU WATSON, AJ
   LAW, CS
   VANSCOY, KA
   MILLERO, FJ
   YAO, W
   FRIEDERICH, GE
   LIDDICOAT, MI
   WANNINKHOF, RH
   BARBER, RT
   COALE, KH
AF WATSON, AJ
   LAW, CS
   VANSCOY, KA
   MILLERO, FJ
   YAO, W
   FRIEDERICH, GE
   LIDDICOAT, MI
   WANNINKHOF, RH
   BARBER, RT
   COALE, KH
TI MINIMAL EFFECT OF IRON FERTILIZATION ON SEA-SURFACE CARBON-DIOXIDE CONCENTRATIONS
SO NATURE
LA English
DT Article
ID sulfur-hexafluoride; seawater; ocean
AB IT has long been hypothesized that iron concentrations limit phytoplankton productivity in some parts of the ocean(1-3). As a result, iron may have played a role in modulating atmospheric CO2 levels between glacial and interglacial times(4), and it has been proposed(5) that large-stale deposition of iron in the ocean might be an effective way to combat the rise of anthropogenic CO2 in the atmosphere. As part of an experiment in the equatorial Pacific Ocean(6), we observed the effect on dissolved CO2 of enriching a small (8 x 8 km) patch of water with iron. We saw significant depression of surface fugacities of CO2 within 48 hours of the iron release, which did not change systematically after that time. But the effect was only a small fraction (similar to 10%) of the CO2 drawdown that would have occurred had the enrichment resulted in the complete utilization of ail the available nitrate and phosphate. Thus artificial fertilization of this ocean region did not cause a very large change in the surface CO2 concentration, in contrast to the effect observed in incubation experiments(3), where addition of similar concentrations of iron usually results in complete depletion of nutrients. Although our experiment does not necessarily mimic all circumstances under which iron deposition might occur naturally, our results do not support the idea that iron fertilization would significantly affect atmospheric CO2 concentrations.
C1 UNIV E ANGLIA,SCH ENVIRONM SCI,NORWICH NR4 7TJ,NORFOLK,ENGLAND.
   UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149.
   MONTEREY BAY AQUARIUM RES INST,PACIFIC GROVE,CA 93950.
   NOAA,ATLANTIC OCEAN MARINE LAB,MIAMI,FL 33149.
   DUKE UNIV,MARINE LAB,BEAUFORT,NC 28516.
   MOSS LANDING MARINE LABS,MOSS LANDING,CA 95039.
C3 University of East Anglia; University of Miami; Monterey Bay Aquarium Research Institute; National Oceanic Atmospheric Admin (NOAA) - USA; Atlantic Oceanographic & Meteorological Laboratory (AOML); Duke University; Moss Landing Marine Laboratories
RP WATSON, AJ (corresponding author), PLYMOUTH MARINE LAB,PROSPECT PL,W HOE,PLYMOUTH PL1 3DH,ENGLAND.
NR 19
TC 66
Z9 70
U1 0
U2 21
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 143
EP 145
DI 10.1038/371143a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100059
DA 2026-03-10
ER

PT J
AU BURR, DC
   MORRONE, MC
   ROSS, J
AF BURR, DC
   MORRONE, MC
   ROSS, J
TI SELECTIVE SUPPRESSION OF THE MAGNOCELLULAR VISUAL PATHWAY DURING SACCADIC EYE-MOVEMENTS
SO NATURE
LA English
DT Article
ID motion perception; macaque monkey; sensitivity; contrast; image
AB VISUAL scientists have long sought to explain why the world remains stable during saccades, the ballistic eye-movements that continually displace the retinal image at fast but resolvable(1) velocities. An early suggestion was that vision may be actively suppressed during saccades(2), but experimental support has been variable(3-5). Here we present evidence that saccadic suppression does occur, but that it is selective for patterns modulated in luminance at low spatial frequencies. Patterns of higher Spatial frequency, and equiluminant patterns (modulated only in colour) at all spatial frequencies were not suppressed during saccades, but actually enhanced. The selectivity of the suppression suggests that it is confined to the colour-blind magnocellular stream (which provides the dominant input to motion centres and areas involved with attention), where it could dull the otherwise disturbing sense of Past low-spatial-frequency image motion. Masking studies suggest that the suppression precedes the site of contrast masking and may therefore occur early in visual processing, possibly as early as the lateral geniculate nucleus.
C1 UNIV ROME, DEPT PSYCHOL, I-00185 ROME, ITALY.
   UNIV WESTERN AUSTRALIA, DEPT PSYCHOL, NEDLANDS, WA 6009, AUSTRALIA.
C3 Sapienza University Rome; University of Western Australia
RP BURR, DC (corresponding author), CNR, IST NEUROFISIOL, VIA S ZENO 51, I-56127 PISA, ITALY.
NR 29
TC 532
Z9 595
U1 1
U2 46
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 511
EP 513
DI 10.1038/371511a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900054
PM 7935763
DA 2026-03-10
ER

PT J
AU TZAMARIAS, D
   STRUHL, K
AF TZAMARIAS, D
   STRUHL, K
TI FUNCTIONAL DISSECTION OF THE YEAST CYC8-TUP1 TRANSCRIPTIONAL CO-REPRESSOR COMPLEX
SO NATURE
LA English
DT Article
ID dna-binding specificity; saccharomyces-cerevisiae; glucocorticoid receptor; glucose repression; activation domain; escherichia-coli; shuttle vectors; protein; genes; purification
AB DNA-BINDING repressor proteins mediate regulation of yeast genes by cell type (Mcm1/alpha 2 and a1/alpha 2), glucose (Mig1) and oxygen (Rox1) (refs 1-4 respectively). An unusual feature of all these regulatory pathways is that transcriptional repression requires two physically associated proteins(5) that do not bind DNA Cyc8(Ssn6) and Tup1. The Cyc8-Tup1 complex has been proposed to be a corepressor that is recruited to target promoters by pathway-specific DNA-binding proteins(6), but the specific functions of the individual proteins are unknown. Here we show that when it is bound upstream of a functional promoter through the LexA DNA-binding domain, Tup1 represses transcription in the absence of Cyc8. Deletion analysis indicates that Tup1 contains at least two non-overlapping transcriptional repression regions with minimal primary sequence similarity, and a separable Cyc8-interaction domain. These Tup1 domains, which do not include the beta-transducin motifs(7), are necessary and partially sufficient for Tup1 function. We suggest that Tup1 performs the repression function of the Cyc8-Tup1 co-repressor complex, and that Cyc8 serves as a link with the pathway-specific DNA-binding proteins.
C1 HARVARD UNIV,SCH MED,DEPT BIOL CHEM & MOLEC PHARMACOL,BOSTON,MA 02115.
C3 Harvard University; Harvard Medical School
NR 30
TC 297
Z9 320
U1 2
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 758
EP 761
DI 10.1038/369758a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100065
PM 8008070
DA 2026-03-10
ER

PT J
AU BIAGGIO, I
   PARTANEN, JP
   AI, B
   KNIZE, RJ
   HELLWARTH, RW
AF BIAGGIO, I
   PARTANEN, JP
   AI, B
   KNIZE, RJ
   HELLWARTH, RW
TI OPTICAL-IMAGE PROCESSING BY AN ATOMIC VAPOR
SO NATURE
LA English
DT Article
AB ATOMIC vapours can exhibit large optical nonlinearities(1). when laser light is tuned in resonance with an atomic transition, the absorption cross-section of the atom can become very large, typically seven orders of magnitude larger than the cross-sectional area of its electron cloud(2). Because of these strong nonlinearities, different laser beams can interact with one another in an atomic vapour, even at intensities as low as a few milliwatts per cm(2). This raises the question(1) of whether atomic vapours can be used as nonlinear optical elements for parallel optical image processing. A well-known example of an all-optical image processor is the optical correlator: laser beams with imprinted images interact in a nonlinear medium to produce a signal beam, the intensity distribution of which is related to the correlation integral of (and hence the degree of similarity between) the input images. Here we demonstrate the use of a caesium-atom vapour as the active medium in such an optical correlator. We show that this system compares favourably with others currently in use, particularly with regard to its power requirements.
C1 UNIV SO CALIF,DEPT PHYS,LOS ANGELES,CA 90089.
C3 University of Southern California
RP BIAGGIO, I (corresponding author), UNIV SO CALIF,DEPT ELECT ENGN,LOS ANGELES,CA 90089, USA.
NR 21
TC 15
Z9 16
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 318
EP 320
DI 10.1038/371318a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400047
DA 2026-03-10
ER

PT J
AU FITZGERALD, SD
   WOODS, AW
AF FITZGERALD, SD
   WOODS, AW
TI THE INSTABILITY OF A VAPORIZATION FRONT IN HOT POROUS ROCK
SO NATURE
LA English
DT Article
ID stability; systems; media; flow
AB IN many geothermal systems, water migrates into vapour-dominated porous rock either through natural recharge or through forced injection of water from a well1-5. If the host rock is initially very hot, then a fraction of this injected water vaporizes6,7; as the water injection rate increases, the fraction which vaporizes decreases7. For modelling purposes, it is generally assumed that liquid-vapour interfaces in hot porous rocks are planar and stable6,7. But we show here, both theoretically and experimentally, that if a sufficient fraction of the liquid vaporizes, the interface can become unstable. The resulting 'fingering' instability can itself be stabilized: at short wavelengths by thermal diffusion, and at long wavelengths by the pressure increase caused by the excess vaporization at the tips of the fingers. These liquid fingers migrate through the porous rock much more rapidly than does a planar liquid front, and could therefore limit the time during which vapour may be extracted for geothermal power applications. We suggest, that an optimal water injection rate for geothermal energy production may be that for which the interface is just stable, thereby maximizing the fraction of liquid which vaporizes, while suppressing the fingering instability.
RP FITZGERALD, SD (corresponding author), INST THEORET GEOPHYS,DEPT APPL MATH & THEORET PHYS,CAMBRIDGE CB3 9EW,ENGLAND.
NR 26
TC 31
Z9 34
U1 1
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 450
EP 453
DI 10.1038/367450a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900051
DA 2026-03-10
ER

PT J
AU TONEY, MF
   HOWARD, JN
   RICHER, J
   BORGES, GL
   GORDON, JG
   MELROY, OR
   WIESLER, DG
   YEE, D
   SORENSEN, LB
AF TONEY, MF
   HOWARD, JN
   RICHER, J
   BORGES, GL
   GORDON, JG
   MELROY, OR
   WIESLER, DG
   YEE, D
   SORENSEN, LB
TI VOLTAGE-DEPENDENT ORDERING OF WATER-MOLECULES AT AN ELECTRODE-ELECTROLYTE INTERFACE
SO NATURE
LA English
DT Article
ID x-ray-diffraction; dynamics; silver; adsorption; surface; simulation; layer; face
AB THE arrangement of water molecules at charged, aqueous interfaces is an important question in electrochemistry, geochemistry and biology. Theoretical studies1-11 suggest that the molecules become arranged in several layers adjacent to a solid interface. with densities similar to that in the bulk, and that the molecules in the first layer are reoriented from oxygen-up to oxygen-down as the electrode charge changes from negative to positive. Few of these predictions have been verified experimentally12-16, however. Using X-ray scattering, we have measured the water density profile perpendicular to a silver (111) surface at two applied voltages. We find that the water molecules are ordered in layers extending about three molecular diameters from the electrode, and that the spacing between the electrode and first water layer indicates an oxygen-up (oxygen-down) average orientation for negative (positive) charge. Contrary to current models, however, we find that the first layer has a far greater density than that in bulk water. This implies that the hydrogen-bonding network is disrupted in this layer, and that the properties of the water in the layer are likely to be very different from those in the bulk.
C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899.
   UNIV WASHINGTON,DEPT PHYS FM15,SEATTLE,WA 98195.
C3 National Institute of Standards & Technology (NIST) - USA; University of Washington; University of Washington Seattle
RP TONEY, MF (corresponding author), IBM CORP,DIV RES,ALMADEN RES CTR,SAN JOSE,CA 95120, USA.
NR 25
TC 583
Z9 640
U1 4
U2 153
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 444
EP 446
DI 10.1038/368444a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000059
DA 2026-03-10
ER

PT J
AU DETRICK, R
   COLLINS, J
   STEPHEN, R
   SWIFT, S
AF DETRICK, R
   COLLINS, J
   STEPHEN, R
   SWIFT, S
TI IN-SITU EVIDENCE FOR THE NATURE OF THE SEISMIC LAYER 2/3 BOUNDARY IN OCEANIC-CRUST
SO NATURE
LA English
DT Article
ID costa-rica rift; east pacific rise; velocity structure; magma chamber; geology; deep; newfoundland; ophiolites; hole-504b; basin
AB THE igneous oceanic crust is typically thought of as comprising two layers: an upper crust ('seismic layer 2') characterized by a rapid increase in seismic velocity with depth, and a thicker lower crust ('seismic layer 3') which is distinguished from layer 2 by both a higher P-wave velocity (6.69 +/- 0.26 km s(-1)) and a much smaller vertical velocity gradient (<1 km s(-1) km(-1))(1-3). A direct correlation has never been established between this seismic layering and the in situ lithological and physical properties of oceanic crust. The transition between seismic layers 2 and 3 has been variously interpreted as a change in igneous rock texture from doleritic sheeted dykes to gabbro(4,5), an increase in metamorphic grade from greenschist- to amphibolite-facies rocks(2,6-9), or a change in bulk crustal porosity with depth(2,10). We have re-examined available seismic refraction data from around Hole 504B, the deepest (>1.8 km) continuous hole drilled into the oceanic crust(11-13), and find that at this location the seismic layer 2/3 boundary lies within the sheeted-dyke complex, where it is associated with gradual downhole changes in crustal porosity and alteration, not a lithological transition from sheeted dykes to gabbro.
RP DETRICK, R (corresponding author), WOODS HOLE OCEANOG INST,DEPT GEOL & GEOPHYS,WOODS HOLE,MA 02543, USA.
NR 32
TC 125
Z9 133
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 288
EP 290
DI 10.1038/370288a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900061
DA 2026-03-10
ER

PT J
AU SAYLES, FL
   MARTIN, WR
   DEUSER, WG
AF SAYLES, FL
   MARTIN, WR
   DEUSER, WG
TI RESPONSE OF BENTHIC OXYGEN-DEMAND TO PARTICULATE ORGANIC-CARBON SUPPLY IN THE DEEP-SEA NEAR BERMUDA
SO NATURE
LA English
DT Article
ID seasonal deposition; north pacific; sargasso sea; panama basin; flux; community; consumption; variability; degradation; atlantic
AB OVER the past decade an increasing body of evidence has accumulated indicating that much, perhaps most, of the deep sea floor is an environment of substantial temporal variability(1-4). This variability is driven largely by seasonal changes of processes occurring in the surface waters(2,3,5). The coupling of the deep sea floor environment to the surface waters is the result of rapid vertical transport of particulate matter through the water column(6-8), affording only limited time for degradation before arrival at the sea floor. Studies in the Pacific Ocean have indicated that temporal variations in particulate organic carbon fluxes to the sea floor are accompanied by temporal variability in sediment oxygen demand by as much as a factor of four(1,2). We report here time-series studies of oxygen fluxes into the sediments of the oligotrophic Atlantic near Bermuda which contrast sharply with these previous reports. At the Bermuda site, despite large seasonal variations in particulate organic carbon fluxes, in situ measured sediment oxygen consumption does not vary significantly. These results imply that large areas of the sea floor may be characterized by seasonally invariant sediment oxygen demand.
RP SAYLES, FL (corresponding author), WOODS HOLE OCEANOG INST,DEPT MARINE CHEM & GEOCHEM,WOODS HOLE,MA 02543, USA.
NR 24
TC 95
Z9 100
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 686
EP 689
DI 10.1038/371686a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300050
DA 2026-03-10
ER

PT J
AU STARK, WM
   PARKER, CN
   BOOCOCK, MR
   HALFORD, SE
AF STARK, WM
   PARKER, CN
   BOOCOCK, MR
   HALFORD, SE
TI STEREOSELECTIVITY OF DNA CATENANE FUSION BY RESOLVASE
SO NATURE
LA English
DT Article
ID site-specific recombination; tn3 resolvase; bacteriophage-lambda; segments; products; res
AB COMMUNICATIONS between distant sites on DNA often depend on the way in which the sites are connected(1,2). For example, site-specific recombination catalysed by Tn3 resolvase is most efficient when the 114-base-pair res recombination sites are directly repeated in the same DNA molecule(3). In vitro a supercoiled plasmid substrate containing two directly repeated res sites gives a resolution product in which the two recombinant circles are topologically linked as a simple (two-noded) catenane (Fig. 1a). Resolvase is highly selective in forming this product rather than unlinked circles or more complex catenanes. It does not catalyse recombination between sites on separate supercoiled molecules, or between inverted sites in the same supercoiled molecule(3-5). Tn3 resolution removes four negative supercoils from the substrate, an energetically favourable change which may drive the reaction(6): in relaxed or nicked circular substrates, resolution is incomplete and slower. Resolvase can catalyse fusion of the circles of a nicked or relaxed catenane, giving a single unknotted circular product(6,7). The fusion is the precise topological reversal of resolution, introducing four negative supercoils into a related catenane substrate(6), and should therefore not proceed if the catenane is already negatively supercoiled. Here we study recombination between res sites in non-supercoiled DNA circles linked into simple catenanes. We used (+2) and (-2) catenanes, which differ only in the direction in which one circle is threaded through the other (Fig. 2a). Although stereoselectivity is a feature of enzyme catalysis, it is not obvious how resolvase can distinguish between these subtly different catenane diastereomers. A model for the intertwining of the res site DNA in the catalytically active complex(4,7) predicts that only the (-2) catenane will recombine, giving unknotted and 4-noded knot circular products. We have confirmed this prediction for the Tn3 and Tn21 resolvases.
C1 UNIV BRISTOL,DEPT BIOCHEM,BRISTOL BS8 1TD,AVON,ENGLAND.
C3 University of Bristol
RP STARK, WM (corresponding author), UNIV GLASGOW,INST GENET,CHURCH ST,GLASGOW G11 5JS,SCOTLAND.
FU Wellcome Trust Funding Source: Medline
NR 20
TC 22
Z9 22
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 76
EP 78
DI 10.1038/368076a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900058
PM 8107889
DA 2026-03-10
ER

PT J
AU ROTHSCHILD, RE
   KULKARNI, SR
   LINGENFELTER, RE
AF ROTHSCHILD, RE
   KULKARNI, SR
   LINGENFELTER, RE
TI DISCOVERY OF AN X-RAY SOURCE COINCIDENT WITH THE SOFT GAMMA-RAY REPEATER-0525-66
SO NATURE
LA English
DT Article
ID large magellanic cloud; burst; remnants; stars
AB ALTHOUGH gamma-ray bursters (GRBs) have been known for more than 20 years, no source has ever been identified in its quiescent state which might provide clues to its nature. On the other hand, two of the three known soft gamma-ray repeaters (SGRs), which emit intermittent bursts of soft gamma-rays. seem to be associated with supernova remnants1,2, and the recent identification of X-rays from one of these, SGR1806 - 20, supports the suggestion that a pulsar inside the remnant is the source of the gamma-rays3-5.  Here we report X-ray observations of SGR0525 - 66, which has been associated previously with the supernova remnant N49 (ref. 1). We identify point-like emission from a source coincident with SGR0525 - 66, which suggests that it too is a pulsar. The pulsar seems to be only about 5,000 years old and has a high transverse velocity of about 1,200 km s-1, and we predict that the plerion (the region of radio synchrotron emission surrounding the pulsar) will be between 0.1 and 0.3 arcsec across. A high birth velocity has been estimated for the pulsar associated with SGR1806 - 20 also4, and this characteristic may be related to the reason why only a very few pulsars become SGRs.
C1 CALTECH,DIV PHYS MATH & ASTRON 10524,PASADENA,CA 91125.
C3 California Institute of Technology
RP ROTHSCHILD, RE (corresponding author), UNIV CALIF SAN DIEGO,CTR ASTROPHYS & SPACE SCI 0111,LA JOLLA,CA 92093, USA.
NR 22
TC 126
Z9 132
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 432
EP 434
DI 10.1038/368432a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000054
DA 2026-03-10
ER

PT J
AU LAND, MF
   LEE, DN
AF LAND, MF
   LEE, DN
TI WHERE WE LOOK WHEN WE STEER
SO NATURE
LA English
DT Article
ID coordination
AB STEERING a car requires visual information from the changing pattern of the road ahead. There are many theories about what features a driver might use(1-3), and recent attempts to engineer self-steering vehicles have sharpened interest in the mechanisms involved(4,5). However, there is little direct information linking steering performance to the driver's direction of gaze(3). We have made simultaneous recordings of steering-wheel angle and drivers' gaze direction during a series of drives along a tortuous road. We found that drivers rely particularly on the 'tangent point' an the inside of each curve, seeking this point 1-2 s before each bend and returning to it throughout the bend. The direction of this point relative to the car's heading predicts the curvature of the road ahead, and we examine the way this information is used.
C1 UNIV EDINBURGH, DEPT PSYCHOL, PERCEPT ACT LABS, EDINBURGH EH8 9JZ, SCOTLAND.
C3 University of Edinburgh
RP LAND, MF (corresponding author), UNIV SUSSEX, SCH BIOL SCI, SUSSEX CTR NEUROSCI, BRIGHTON BN1 9QG, ENGLAND.
NR 12
TC 734
Z9 830
U1 0
U2 91
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 742
EP 744
DI 10.1038/369742a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100059
PM 8008066
DA 2026-03-10
ER

PT J
AU TANJI, J
   SHIMA, K
AF TANJI, J
   SHIMA, K
TI ROLE FOR SUPPLEMENTARY MOTOR AREA CELLS IN PLANNING SEVERAL MOVEMENTS AHEAD
SO NATURE
LA English
DT Article
ID neuronal-activity; voluntary movements; cortical areas; arm movements; cortex; monkey; activation; potentials; primates; premotor
AB To achieve a volitional goal, we need to execute multiple movements in a specific temporal order. After repetitive performance of a particular sequence of movements, we are able to memorize and execute the whole sequence without external guidance. Where and how in the brain do we store information necessary for the orderly performance of multiple movements? We have found a group of cells in the cerebral cortex of monkeys whose activity is exclusively related to a sequence of multiple movements performed in a particular order. Such cellular activity exists in the supplementary motor area(1,2), but not in the primary motor cortex(3,4). We propose that these cells contribute a signal about the order of forthcoming multiple movements, and are useful for planning and coding of several movements ahead.
RP TANJI, J (corresponding author), TOHOKU UNIV,SCH MED,DEPT PHYSIOL,AOBA KU,2-1 SEIRYO CHO,SENDAI,MIYAGI 980,JAPAN.
NR 27
TC 524
Z9 587
U1 0
U2 24
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 413
EP 416
DI 10.1038/371413a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500041
PM 8090219
DA 2026-03-10
ER

PT J
AU BRONNER, G
   CHULAGRAFF, Q
   DOE, CQ
   COHEN, B
   WEIGEL, D
   TAUBERT, H
   JACKLE, H
AF BRONNER, G
   CHULAGRAFF, Q
   DOE, CQ
   COHEN, B
   WEIGEL, D
   TAUBERT, H
   JACKLE, H
TI SP1/EGR-LIKE ZINC-FINGER PROTEIN REQUIRED FOR ENDODERM SPECIFICATION AND GERM-LAYER FORMATION IN DROSOPHILA
SO NATURE
LA English
DT Article
ID embryonic termini; segmentation gene; melanogaster; gastrulation; tailless; domains; member; cells; sp1
AB Much of out present knowledge of the biological processes involved in pattern formation in Drosophila is derived from segmentation analysis(1,2). Comparatively little is known about the genetic requirement and mechanisms underlying the formation and separation of germ layers by morphogenetic movements during gastrulation(3). Here we show that the Drosophila gene huckebein (hkb), a member of the gap-gene class of segmentation genes(4,5), is required for germ-layer formation at blastoderm. Absence of the hkb product, an Spl/egr-like zinc-finger protein, causes the ectodermal and mesodermal primordia to expand at the expense of endoderm anlagen. Conversely, ectopic expression of hkb inhibits the formation of the major gastrulation fold which gives rise to the mesoderm and prevents normal segmentation in the ectoderm. Thus, hkb is necessary for endoderm development and its activity defines spatial limits within the blastoderm embryo in which the germ layers are established.
C1 UNIV ILLINOIS,DEPT CELL & STRUCT BIOL,URBANA,IL 61801.
C3 University of Illinois System; University of Illinois Urbana-Champaign
RP BRONNER, G (corresponding author), MAX PLANCK INST BIOPHYS CHEM,MOLEK ENTWICKLUNGSBIOL ABT,POSTFACH 2841,D-37018 GOTTINGEN,GERMANY.
NR 30
TC 115
Z9 122
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 664
EP 668
DI 10.1038/369664a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900060
PM 8208294
DA 2026-03-10
ER

PT J
AU MUSCATELLI, F
   STROM, TM
   WALKER, AP
   ZANARIA, E
   RECAN, D
   MEINDL, A
   BARDONI, B
   GUIOLI, S
   ZEHETNER, G
   RABL, W
   SCHWARZ, HP
   KAPLAN, JC
   CAMERINO, G
   MEITINGER, T
   MONACO, AP
AF MUSCATELLI, F
   STROM, TM
   WALKER, AP
   ZANARIA, E
   RECAN, D
   MEINDL, A
   BARDONI, B
   GUIOLI, S
   ZEHETNER, G
   RABL, W
   SCHWARZ, HP
   KAPLAN, JC
   CAMERINO, G
   MEITINGER, T
   MONACO, AP
TI MUTATIONS IN THE DAX-1 GENE GIVE RISE TO BOTH X-LINKED ADRENAL HYPOPLASIA CONGENITA AND HYPOGONADOTROPIC HYPOGONADISM
SO NATURE
LA English
DT Article
ID glycerol kinase-deficiency; restriction map; induce puberty; hemophilia-a; xp21; deletion; failure; cloning; distal; contig
AB ADRENAL hypoplasia congenita (AHC) is an X-linked disorder characterized by primary adrenal insufficiency(1,2). Hypogonadotropic hypogonadism (HHG) is frequently associated with this disorder but is thought not to be caused by the low adrenal androgen levels due to adrenal hypoplasia(3,4). It is uncertain whether there are two distinct yet physically linked genes responsible for AHC and HHG or a single gene responsible for both diseases. AHC can occur as a part of a contiguous deletion syndrome together with Duchenne muscular dystrophy (DMD) and/or glycerol kinase deficiency (GKD). From the analysis of deletions, the following gene order has been deduced: Xpter-AHC-GKD-DMD-cen(5,6). An AHC critical region of 200-500 kilobases has been defined by physical mapping(7,8) and partially overlaps with a 160-kilobase dosage-sensitive sex (DSS) reversal critical region(9). The DAX-1 (DSS-AHC critical region on the X, gene 1) gene was isolated and found to encode a new member of the nuclear hormone receptor family(10). Here we report that DAX-1 is deleted in 14 patients and point mutations were found in the coding region in DNA from 12 unrelated individuals. All AHC patients over 14 years old and with only point mutations in DAX-1 mere also diagnosed with HHG, confirming that the DAX-1 gene is responsible for both X-linked AHC and HHG. But in four sporadic cases and a single familial case, no point mutations were found, suggesting genetic heterogeneity or differential expression of DAX-1.
C1 UNIV MUNICH,KINDERPOLIKLIN,PADIAT GENET ABT,D-80336 MUNICH,GERMANY.
   UNIV PAVIA,I-27100 PAVIA,ITALY.
   HOP COCHIN,F-75014 PARIS,FRANCE.
   ICRF LABS,LONDON WC2A 3PX,ENGLAND.
   TECH UNIV MUNICH,KINDERKLIN,D-80804 MUNICH,GERMANY.
   UNIV MUNICH,DR VON HAUNERSCHES KINDERSPITAL,D-80337 MUNICH,GERMANY.
C3 University of Munich; University of Pavia; Assistance Publique Hopitaux Paris (APHP); Universite Paris Cite; Hopital Universitaire Cochin - APHP; Technical University of Munich; University of Munich
RP MUSCATELLI, F (corresponding author), JOHN RADCLIFFE HOSP,INST MOLEC MED,IMPERIAL CANC RES FUND LABS,OXFORD OX3 9DU,ENGLAND.
FU Telethon [B.05] Funding Source: Medline
NR 29
TC 609
Z9 658
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 672
EP 676
DI 10.1038/372672a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700085
PM 7990958
DA 2026-03-10
ER

PT J
AU STUART, GJ
   SAKMANN, B
AF STUART, GJ
   SAKMANN, B
TI ACTIVE PROPAGATION OF SOMATIC ACTION-POTENTIALS INTO NEOCORTICAL PYRAMIDAL CELL DENDRITES
SO NATURE
LA English
DT Article
ID long-term potentiation; hippocampal-neurons; rat hippocampus; visual-cortex; thresholds; initiation; induction; channels; synapses; slices
AB THE dendrites of neurons in the mammalian central nervous system have been considered as electrically passive structures which funnel synaptic potentials to the soma and axon initial segment, the site of action potential initiation1,2.More recent studies, however, have shown that the dendrites of many neurons are not passive, but contain active conductances3,4. The role of these dendritic voltage-activated channels in the initiation of action potentials in neurons is largely unknown. To assess this directly, patch-clamp recordings were made from the dendrites of neocortical pyramidal cells in brain slices.  Voltage-activated sodium currents were observed in dendritic outside-out patches, while action potentials could be evoked by depolarizing current pulses or by synaptic stimulation during dendritic whole-cell recordings.  To determine the site of initiation of these action potentials, simultaneous whole-cell recordings were made from the soma and the apical dendrite or axon of the same cell.  These experiments showed that action potentials are initiated first in the axon and then actively propagate back into the dendritic tree.
RP STUART, GJ (corresponding author), MAX PLANCK INST MED RES,ZELLPHYSIOL ABT,POSTFACH 103820,D-69028 HEIDELBERG,GERMANY.
NR 30
TC 1004
Z9 1112
U1 3
U2 67
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 69
EP 72
DI 10.1038/367069a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500061
PM 8107777
DA 2026-03-10
ER

PT J
AU MITZI, DB
   FEILD, CA
   HARRISON, WTA
   GULOY, AM
AF MITZI, DB
   FEILD, CA
   HARRISON, WTA
   GULOY, AM
TI CONDUCTING TIN HALIDES WITH A LAYERED ORGANIC-BASED PEROVSKITE STRUCTURE
SO NATURE
LA English
DT Article
ID superconductivity; evolution; system; cu
AB THE discovery(1) of high-temperature superconductivity in layered copper oxide perovskites has generated considerable fundamental and technological interest in this class of materials. Only a few other examples of conducting layered perovskites are known; these are also oxides such as (La1-xSrx)(n+1)Mn(n)O3(n+1) (ref. 2), Lan+1NinO3n+1 (ref. 3) and Ban+1PbnO3n+1 (ref. 4), all of which exhibit a trend from semiconducting to metallic behaviour with increasing number of perovskite layers (n). We report here the synthesis of a family of organic-based layered halide perovskites, (C4H9NH3)(2)(CH3NH3)(n-1)SnnI3n+1, which show a similar transition from semiconducting to metallic behaviour with increasing n. The incorporation of an organic modulation layer between the conducting tin iodide sheets potentially provides greater flexibility for tuning the electrical properties of the perovskite sheets, and we suggest that such an approach will prove valuable for exploring the range of transport properties possible with layered perovskites.
C1 UNIV HOUSTON,DEPT CHEM,HOUSTON,TX 77204.
   UNIV HOUSTON,TEXAS CTR SUPERCONDUCT,HOUSTON,TX 77204.
C3 University of Houston System; University of Houston; University of Houston System; University of Houston
RP MITZI, DB (corresponding author), IBM CORP,THOMAS J WATSON RES CTR,BOX 218,YORKTOWN HTS,NY 10598, USA.
NR 14
TC 937
Z9 1080
U1 5
U2 522
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 467
EP 469
DI 10.1038/369467a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600050
DA 2026-03-10
ER

PT J
AU MOREL, FMM
   REINFELDER, JR
   ROBERTS, SB
   CHAMBERLAIN, CP
   LEE, JG
   YEE, D
AF MOREL, FMM
   REINFELDER, JR
   ROBERTS, SB
   CHAMBERLAIN, CP
   LEE, JG
   YEE, D
TI ZINC AND CARBON CO-LIMITATION OF MARINE-PHYTOPLANKTON
SO NATURE
LA English
DT Article
ID natural organic-ligands; central north pacific; inorganic-carbon; growth; complexation; transport; anhydrase; dioxide; cadmium; diatom
AB PROCESSES that control carbon uptake by marine phytoplankton are important in the global carbon cycle(1-3). Uptake of CO2 itself may be limited by diffusion(4). Bicarbonate uptake may be limited by zinc as HCO3- transport appears to involve the zinc metalloenzyme carbonic anhydrase(5,6) and the concentration of inorganic zinc in seawater(7) is low enough to limit the growth of certain phytoplankton in culture(8,9). Here we show that HCO3- uptake by the marine diatom Thalassiosira weissflogii is modulated by the partial pressure of CO2 and by the concentration of inorganic Zn (for which Cd and Co may substitute in carbonic anhydrase). This result leads naturally to a 'zinc hypothesis' which, like the standing 'iron hypothesis'(10), posits that Zn (Fe) may limit oceanic production and influence the global carbon cycle. Because of the large C-13 enrichment of HCO3- over CO2, our results may be important for the interpretation of delta(13)C measurements in seawater and sediments.
C1 DARTMOUTH COLL,DEPT EARTH SCI,HANOVER,NH 03755.
C3 Dartmouth College
RP MOREL, FMM (corresponding author), MIT,RALPH M PARSONS LAB,CAMBRIDGE,MA 02139, USA.
NR 27
TC 410
Z9 465
U1 3
U2 116
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 740
EP 742
DI 10.1038/369740a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100058
DA 2026-03-10
ER

PT J
AU ALLAIRE, M
   CHERNAIA, MM
   MALCOLM, BA
   JAMES, MNG
AF ALLAIRE, M
   CHERNAIA, MM
   MALCOLM, BA
   JAMES, MNG
TI PICORNAVIRAL 3C CYSTEINE PROTEINASES HAVE A FOLD SIMILAR TO CHYMOTRYPSIN-LIKE SERINE PROTEINASES
SO NATURE
LA English
DT Article
ID hepatitis-a virus; macromolecular structures; weissenberg camera; diffraction data; crystallography; mutagenesis; refinement; proteases; program
AB THE picornavirus family includes several pathogens such as poliovirus, rhinovirus (the major cause of the common cold), hepatitis A virus and the foot-and-mouth disease virus. Picornaviral proteins are expressed by direct translation of the genomic RNA into a single, large polyprotein precursor(1,2). Proteolysis of the viral polyprotein into the mature proteins is assured by the viral 3C enzymes, which are cysteine proteinases(3-6). Here we report the Xray crystal structure at 2.3 Angstrom resolution of the 3C proteinase from hepatitis A virus (HAV-3C). The overall architecture of HAV-3C reveals a fold resembling that of the chymotrypsin family of serine proteinases, which is consistent with earlier predictions(7,8). Catalytic residues include Cys 172 as nucleophile and His 44 as general base. The 3C cleavage specificity for glutamine residues is defined primarily by His 191. The overall structure suggests that an intermolecular (trans) cleavage releases 3C and that there is an active proteinase in the polyprotein.
C1 UNIV ALBERTA,DEPT BIOCHEM,MRC,PROT STRUCT & FUNCT GRP,EDMONTON T6G 2H7,AB,CANADA.
   UNIV ALBERTA,DEPT BIOCHEM,EDMONTON T6G 2H7,AB,CANADA.
   UNIV ALBERTA,DEPT MED MICROBIOL & INFECT DIS,EDMONTON T6G 2H7,AB,CANADA.
C3 University of Alberta; University of Alberta; University of Alberta
NR 30
TC 267
Z9 300
U1 0
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 5
PY 1994
VL 369
IS 6475
BP 72
EP 76
DI 10.1038/369072a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NJ860
UT WOS:A1994NJ86000056
PM 8164744
DA 2026-03-10
ER

PT J
AU NOBORI, T
   MIURA, K
   WU, DJ
   LOIS, A
   TAKABAYASHI, K
   CARSON, DA
AF NOBORI, T
   MIURA, K
   WU, DJ
   LOIS, A
   TAKABAYASHI, K
   CARSON, DA
TI DELETIONS OF THE CYCLIN-DEPENDENT KINASE-4 INHIBITOR GENE IN MULTIPLE HUMAN CANCERS
SO NATURE
LA English
DT Article
ID human gliomas; short arm; chromosome-9; melanoma
AB CYTOGENETIC abnormalities of chromosome 9p21 are characteristic of malignant melanomas(1,2), gliomas(3), lung cancers(4) and leukaemias(5). From a panel of 46 human malignant cell lines, we localized by positional cloning the most frequently deleted region on 9p21. Sequence analysis of the isolated fragment reveals two open reading frames identical to the recently described complementary DNA for the inhibitor of cyclin-dependent kinase 4 (CDK4)(6). Polymerase chain reaction and Southern blot analysis confirmed the frequent deletion or rearrangement of the CDK4-inhibitor gene in melanomas, gliomas, lung cancers and leukaemias, and the absence of detectable gene transcripts. One carcinoma had a deletion entirety within the CDK4-inhibitor gene. The CDK4-inhibitor gene from a patient with dysplastic nevus syndrome had a germ-line nonsense mutation. The CDK4 inhibitor is thought to be a physiological suppressor of proliferation. Cells unable to produce the inhibitor may be prone to neoplastic transformation.
C1 CIBA GEIGY AG,DIV PHARMACEUT,CH-4002 BASEL,SWITZERLAND.
C3 Novartis
RP NOBORI, T (corresponding author), UNIV CALIF SAN DIEGO,DEPT MED,9500 GILMAN DR,LA JOLLA,CA 92093, USA.
NR 13
TC 1761
Z9 1983
U1 0
U2 38
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 753
EP 756
DI 10.1038/368753a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300062
PM 8152487
DA 2026-03-10
ER

PT J
AU HENGARTNER, MO
   HORVITZ, HR
AF HENGARTNER, MO
   HORVITZ, HR
TI ACTIVATION OF C-ELEGANS CELL-DEATH PROTEIN CED-9 BY AN AMINO-ACID SUBSTITUTION IN A DOMAIN CONSERVED IN BCL-2
SO NATURE
LA English
DT Article
ID caenorhabditis-elegans; sequence similarity; follicular lymphoma; gene; translocation; expression; nematode; cloning
AB THE Caenorhabditis elegans gene ced-9 and the human protooncogene bcl-2 both of which protect cells from programmed cell death, are members of the same gene family(1-11). ced-9 and bcl-2 were discovered because of the effects of dominant gain-of-function mutations(12-14). Such bcl-2 mutations, which are commonly found in follicular lymphoma, are translocations that result in overexpression of a normal Bcl-2 protein in B cells(1,13-16) Here we report that, by contrast, the ced-9(n1950) gain-of-function mutation affects the open reading frame of ced-9 and results in a glycine-to-glutamate substitution in a region highly conserved among all ced-9/bcl-2 family members. We conclude that this glycine has an important function in ced-9 regulation, and we suggest that alteration of this glycine in other members of the ced-9/bcl-2 family might lead to oncogenic activation. We also present genetic evidence suggesting that the CED-9 protein might exist in two distinct forms that have opposite effects on cell death.
C1 MIT,HOWARD HUGHES MED INST,DEPT BIOL,CAMBRIDGE,MA 02139.
C3 Massachusetts Institute of Technology (MIT); Howard Hughes Medical Institute
NR 28
TC 160
Z9 197
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 318
EP 320
DI 10.1038/369318a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900049
PM 7910376
DA 2026-03-10
ER

PT J
AU PERRETT, DI
   MAY, KA
   YOSHIKAWA, S
AF PERRETT, DI
   MAY, KA
   YOSHIKAWA, S
TI FACIAL SHAPE AND JUDGMENTS OF FEMALE ATTRACTIVENESS
SO NATURE
LA English
DT Article
ID physical attractiveness; faces; perception; average; beauty
AB THE finding that photographic(1-4) and digital(5) composites (blends) of faces are considered to be attractive has led to the claim that attractiveness is averageness(5). This would encourage stabilizing selection, favouring phenotypes with an average facial structure(5). The 'averageness hypothesis' would account for the low distinctiveness of attractive faces(6) but is difficult to reconcile with the finding that some facial measurements correlate with attractiveness(7,8). An average face shape is attractive but may not be optimally attractive(9). Human preferences may exert directional selection pressures, as with the phenomena of optimal outbreeding and sexual selection for extreme characteristics(10-14). Using composite faces, we show here that, contrary to the averageness hypothesis, the mean shape of a set of attractive faces is preferred to the mean shape of the sample from which the faces were selected. In addition, attractive composites can be made more attractive by exaggerating the shape differences from the sample mean. Japanese and caucasian observers showed the same direction of preferences for the same facial composites, suggesting that aesthetic judgements of face shape are similar across different cultural backgrounds. Our finding that highly attractive facial configurations are not average shows that preferences could exert a directional selection pressure on the evolution of human face shape.
C1 OTEMON GAKUIN UNIV,FAC LETTERS,DEPT PSYCHOL,IBARAKI,OSAKA 567,JAPAN.
RP PERRETT, DI (corresponding author), UNIV ST ANDREWS,SCH PSYCHOL,ST ANDREWS KY16 9JU,FIFE,SCOTLAND.
NR 20
TC 574
Z9 640
U1 2
U2 161
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 239
EP 242
DI 10.1038/368239a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000054
PM 8145822
DA 2026-03-10
ER

PT J
AU FARRANT, M
   FELDMEYER, D
   TAKAHASHI, T
   CULLCANDY, SG
AF FARRANT, M
   FELDMEYER, D
   TAKAHASHI, T
   CULLCANDY, SG
TI NMDA-RECEPTOR CHANNEL DIVERSITY IN THE DEVELOPING CEREBELLUM
SO NATURE
LA English
DT Article
ID methyl-d-aspartate; neurons; rat; glutamate; activation; currents; adult; cells; distinction; responses
AB IN the cerebellum, NMDA (N-methyl-D-aspartate) receptors play an important role in neuronal differentiation(1,2) and excitatory synaptic transmission(3-5). During early cerebellar development, marked changes occur in the distribution of messenger RNAs encoding various NMDA-receptor subunits(6). To determine whether these changes result in the appearance of functionally distinct NMDA receptors(7-9), we have recorded single-channel currents in rat cerebellar granule cells during the period of their migration from the external germinal layer to the inner granular layer(10). Here we show that before synapse formation(10,11), pre-migratory and migrating granule cells express NMDA receptors possessing single-channel properties similar to those previously described for many central neurons(12,16). In contrast, mature post-migratory cells also express an atypical form of NMDA receptor that has a lower single-channel conductance and distinct kinetic behaviour. The properties of these 'low-conductance' channels correspond to those described(17) for recombinant NMDA receptors formed by coexpression of NR1 and NR2C subunits(8,9). The NR2C subunit appears postnatally and is found predominantly in the adult cerebellum(6-8). Our data demonstrate developmental changes in NMDA-receptor properties at the single-channel level, and suggest that is the cerebellum the expression of a specific subunit protein results in a distinct form of native receptor.
C1 UNIV TOKYO, FAC MED,INST BRAIN RES,DEPT NEUROPHYSIOL,BUNKYO KU, TOKYO 113, JAPAN.
C3 University of Tokyo
RP FARRANT, M (corresponding author), UCL, DEPT PHARMACOL, GOWER ST, LONDON WC1E 6BT, ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 31
TC 270
Z9 298
U1 0
U2 6
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 335
EP 339
DI 10.1038/368335a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500046
PM 7907398
DA 2026-03-10
ER

PT J
AU GEARING, AJH
   BECKETT, P
   CHRISTODOULOU, M
   CHURCHILL, M
   CLEMENTS, J
   DAVIDSON, AH
   DRUMMOND, AH
   GALLOWAY, WA
   GILBERT, R
   GORDON, JL
   LEBER, TM
   MANGAN, M
   MILLER, K
   NAYEE, P
   OWEN, K
   PATEL, S
   THOMAS, W
   WELLS, G
   WOOD, LM
   WOOLLEY, K
AF GEARING, AJH
   BECKETT, P
   CHRISTODOULOU, M
   CHURCHILL, M
   CLEMENTS, J
   DAVIDSON, AH
   DRUMMOND, AH
   GALLOWAY, WA
   GILBERT, R
   GORDON, JL
   LEBER, TM
   MANGAN, M
   MILLER, K
   NAYEE, P
   OWEN, K
   PATEL, S
   THOMAS, W
   WELLS, G
   WOOD, LM
   WOOLLEY, K
TI PROCESSING OF TUMOR-NECROSIS-FACTOR-ALPHA PRECURSOR BY METALLOPROTEINASES
SO NATURE
LA English
DT Article
ID collagen-induced arthritis; tissue inhibitor; rabbit bone; cells; secretion; timp-2
AB TUMOUR necrosis factor-alpha (TNF-alpha) is a potent pro-inflammatory and immunomodulatory cytokine implicated in inflammatory conditions such as rheumatoid arthritis, Crohn's disease, multiple sclerosis and the cachexia associated with cancer or human immunodeficiency virus infection(1). TNF-alpha is initially expressed as a 233-amino-acid membrane-anchored precursor which is proteolytically processed to yield the mature, 157-amino-acid cytokine(2). The processing enzyme(s) which cleave TNF-alpha are unknown. Here we show that the release of mature TNF-alpha from leukocytes cultured in vitro is specifically prevented by synthetic hydroxamic acid-based metalloproteinase inhibitors, which also prevent the release of TNF-alpha into the circulation of endotoxin challenged rats. A recombinant, truncated TNF-alpha precursor is cleaved to biologically active, mature TNF-alpha by several matrix metalloproteinase enzymes. These results indicate that processing of the TNF-alpha precursor is dependent on at least one matrix metalloproteinase-like enzyme, inhibition of which represents a novel therapeutic mechanism for interfering with TNF-alpha production.
C1 BRITISH BIOTECHNOL LTD, OXFORD OX4 5LY, ENGLAND.
NR 21
TC 1131
Z9 1255
U1 0
U2 21
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 555
EP 557
DI 10.1038/370555a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700054
PM 8052310
DA 2026-03-10
ER

PT J
AU SCHUTZE, K
   CLEMENTSENGEWALD, A
AF SCHUTZE, K
   CLEMENTSENGEWALD, A
TI CATCH AND MOVE - CUT OR FUSE
SO NATURE
LA English
DT Article
ID optical tweezers; laser microbeam; membrane-glycoproteins; human sperm; cell; trap; micromanipulation; manipulation; velocity; biology
C1 UNIV MUNICH, WOMENS HOSP, DEPT INVITRO FERTILIZAT, D-80337 MUNICH, GERMANY.
C3 University of Munich
RP SCHUTZE, K (corresponding author), MUNICIPAL HOSP HARLACHING, APPLICAT LASER UNIT, SANATORIUMSPL 2, D-81545 MUNICH, GERMANY.
NR 41
TC 73
Z9 76
U1 0
U2 7
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 667
EP 669
DI 10.1038/368667a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200072
PM 8145856
DA 2026-03-10
ER

PT J
AU SURH, CD
   SPRENT, J
AF SURH, CD
   SPRENT, J
TI T-CELL APOPTOSIS DETECTED IN-SITU DURING POSITIVE AND NEGATIVE SELECTION IN THE THYMUS
SO NATURE
LA English
DT Article
ID monoclonal-antibody; complex; death; identification; thymocytes; medulla; invivo
AB BECAUSE of positive and negative selection to molecules of the major histocompatibility complex (MHC)(1), only a small proportion of the massive numbers of T cells generated is the thymus are selected for expert(2,3). Immature thymocytes have a rapid turnover(2), and it has long been assumed that most thymocytes die in situ(4,5), presumably from apoptosis(6). This has yet to be proved, however, and conventional staining techniques have shown only minimal evidence of cell death in the normal thymus(7,8). Using a method for detecting cells with DNA strand breaks, we now present direct evidence for apoptosis in the normal thymus. In sections of thymus from adult mice, apoptotic cells are scattered throughout the cortex and are engulfed locally by F4/80(+) macrophages. Apoptosis in the thymic cortex is not reduced in MHC-deficient mice, which suggests that T-cell death is primarily a reflection of lack of positive selection rather than negative selection. Direct evidence for apoptosis due to negative selection was obtained by crossing a V beta 5 transgenic line(9) to I-E(+) and I-E(-) mice: I-E(+) mice are known to eliminate V beta 5(+) T cells in the thymus whereas I-E(-) mice do not(10). In marked contrast to I-E(-) mice, the medulla of I-E(+) V beta 5 transgenic mice contains dense aggregates of apoptotic cells; these cells are engulfed by a distinct population of F4/80(-) MAC-3(+) macrophages. Negative selection of V beta 5(+) cells is thus restricted to the medulla.
RP SURH, CD (corresponding author), SCRIPPS RES INST, DEPT IMMUNOL IMM4, 10666 N TORREY PINES RD, LA JOLLA, CA 92037 USA.
NR 29
TC 915
Z9 1046
U1 0
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 100
EP 103
DI 10.1038/372100a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800082
PM 7969401
DA 2026-03-10
ER

PT J
AU BOHRINGER, H
   BRIEL, UG
   SCHWARZ, RA
   VOGES, W
   HARTNER, G
   TRUMPER, J
AF BOHRINGER, H
   BRIEL, UG
   SCHWARZ, RA
   VOGES, W
   HARTNER, G
   TRUMPER, J
TI THE STRUCTURE OF THE VIRGO CLUSTER OF GALAXIES FROM ROSAT X-RAY IMAGES
SO NATURE
LA English
DT Article
ID coma cluster; morphology; mass; sky
AB THE Virgo cluster(1-10) is the nearest large concentration of galaxies to us, and therefore plays a critical role in calibrating the cosmological distance scale(11). Unfortunately, the cluster is very irregular, making it difficult to model the distribution of mass within it, and therefore impossible to determine its content of dark matter. X-ray observations offer a way around this problem, by revealing the hot, diffuse gas that is thought to fill the cluster's gravitational potential well in a way that closely matches the total distribution of mass(12). Here we report X-ray images of Virgo, obtained with the Rosat observatory, which show hot luminous gas extending over most of the optically visible cluster. The data show that a large part of the mass of the cluster is centred on the galaxy M87, with smaller concentrations around M86 and M49. Our results for M86 support the recent suggestion(3) that it is part of a small group of galaxies that is merging with the main cluster.
RP BOHRINGER, H (corresponding author), MAX PLANCK INST EXTRATERR PHYS, D-85740 GARCHING, GERMANY.
NR 32
TC 286
Z9 302
U1 0
U2 1
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 828
EP 831
DI 10.1038/368828a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700062
DA 2026-03-10
ER

PT J
AU WORONICZ, JD
   CALNAN, B
   NGO, V
   WINOTO, A
AF WORONICZ, JD
   CALNAN, B
   NGO, V
   WINOTO, A
TI REQUIREMENT FOR THE ORPHAN STEROID-RECEPTOR NUR77 IN APOPTOSIS OF T-CELL HYBRIDOMAS
SO NATURE
LA English
DT Article
ID growth-factors encodes; factor-inducible gene; dna-binding; expression vectors; ngfi-b; death; protein; superfamily; induction; member
AB APOPTOSIS is a phenomenon observed during development of many cell types in many organisms. It is an internal, programmed cell death characterized by DNA fragmentation into nucleosome-size pieces1-3. Anti-CD3-induced apoptosis in T-cell hybridomas and immature thymocytes requires new gene transcription and may be related to negative selection during T-cell development4-6. Using subtractive hybridization, we isolated a complementary DNA clone encoding the orphan steroid receptor Nur77 (refs 7-9). It shows different patterns of messenger RNA induction between apoptotic and stimulated T cells. We report here the use of gel shift analysis to demonstrate that the Nur77 protein is present at high levels in apoptotic T-cell hybridomas and apoptotic thymocytes, but not in growing T cells or stimulated splenocytes. A Nur77 dominant negative protected T-cell hybridomas from activation-induced apoptosis. Hence Nur77 is necessary for induced apoptosis in T-cell hybridomas.
C1 UNIV CALIF BERKELEY,DEPT MOLEC & CELL BIOL,DIV IMMUNOL,BERKELEY,CA 94720.
   UNIV CALIF BERKELEY,CANC RES LAB,BERKELEY,CA 94720.
C3 University of California System; University of California Berkeley; University of California System; University of California Berkeley
NR 31
TC 514
Z9 564
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 277
EP 281
DI 10.1038/367277a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400058
PM 8121493
DA 2026-03-10
ER

PT J
AU SCHLUTER, AD
   LOFFLER, M
   ENKELMANN, V
AF SCHLUTER, AD
   LOFFLER, M
   ENKELMANN, V
TI SYNTHESIS OF A FULLY UNSATURATED ALL-CARBON LADDER POLYMER
SO NATURE
LA English
DT Article
ID c-60; diodes
AB FOR some time we have been trying to synthesize structurally perfect, fully unsaturated, double-stranded (ladder) polymers(1); such polymers might combine favourable electronic properties with processability. Here we report the successful synthesis of the fully unsaturated ladder polymer 1a (Fig. 1), by way of the Diels-Alder precursor polymer 7 (Fig. 4). The structure of 1a closely resembles the hypothetical open-chain, Polymeric analogue of the belt-region of the icosahedral C-60 (refs 2, 3) molecule, 1b (Fig. 1). Polymer 1a, despite its extended pi-conjugation, is stable in oxygen and may therefore be of interest for electroluminescence and photovoltaics applications(4). Owing to both the relatively mild reaction conditions required for its generation and its double-stranded structure, we expect 1a to have less interruptions of the pi-molecular orbital delocalization along the backbone as compared with the single-stranded polymer poly(phenylene vinylene), which is presently the material of prime interest for the active elements in light-emitting diodes(5,6).
C1 MAX PLANCK INST POLYMER RES,D-55021 MAINZ,GERMANY.
C3 Max Planck Society
RP SCHLUTER, AD (corresponding author), FREE UNIV BERLIN,INST ORGAN CHEM,TAKUSTR 3,D-14195 BERLIN,GERMANY.
NR 12
TC 100
Z9 112
U1 0
U2 35
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 831
EP 834
DI 10.1038/368831a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700063
DA 2026-03-10
ER

PT J
AU JIN, ZM
   GREEN, HW
   ZHOU, Y
AF JIN, ZM
   GREEN, HW
   ZHOU, Y
TI MELT TOPOLOGY IN PARTIALLY MOLTEN MANTLE PERIDOTITE DURING DUCTILE DEFORMATION
SO NATURE
LA English
DT Article
ID dynamic recrystallization; olivine; beneath; water; microstructures; anisotropy; bischofite; carnallite; rheology; creep
AB THE process by which basaltic melt is generated and extracted beneath mid-ocean ridges is poorly understood. Knowledge of the distribution of melt within the parent mantle peridotite during the early stages of melting is important for interpretation of geophysical experiments and for construction of models of magma coalescence and extraction(1-4). Static experiments on mantle rocks and selected analogue materials have shown that, for small melt fractions, melt is concentrated along three-grain intersections, forming an interconnected web of tubes(5-9). Low-pressure deformation experiments on olivine + melt specimens have yielded the same conclusion(10,11). But in similar experiments on salt-brine mixtures during ductile deformation, the fluid emerges from the triple junctions where it resides under static conditions and spreads onto grain boundaries(12-16). Here we report the results of low-stress deformation experiments on partially molten peridotite at mantle temperatures and pressures, which show that such dynamic melting produces microstructures analogous to those of the salt-brine experiments. The very low viscosity of these specimens suggests that in the Earth, dynamic wetting could lead to melt separation at very low melt fractions, and to melt focusing at ridges.
C1 UNIV CALIF RIVERSIDE,DEPT EARTH SCI,RIVERSIDE,CA 92521.
   CHINA UNIV GEOSCI,DEPT GEOMECH,WUHAN 430074,PEOPLES R CHINA.
C3 University of California System; University of California Riverside; China University of Geosciences
RP JIN, ZM (corresponding author), UNIV CALIF RIVERSIDE,INST GEOPHYS & PLANETARY PHYS,RIVERSIDE,CA 92521, USA.
NR 38
TC 138
Z9 172
U1 22
U2 143
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 164
EP 167
DI 10.1038/372164a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800051
DA 2026-03-10
ER

PT J
AU SAUBER, J
   THATCHER, W
   SOLOMON, SC
   LISOWSKI, M
AF SAUBER, J
   THATCHER, W
   SOLOMON, SC
   LISOWSKI, M
TI GEODETIC SLIP RATE FOR THE EASTERN CALIFORNIA SHEAR ZONE AND THE RECURRENCE TIME OF MOJAVE DESERT EARTHQUAKES
SO NATURE
LA English
DT Article
ID san-andreas fault; southern-california; motion
AB WHERE the San Andreas fault passes along the southwestern margin of the Mojave desert, it exhibits a large change in trend, and the deformation associated with the Pacific/North American plate boundary is distributed broadly over a complex shear zone. The importance of understanding the partitioning of strain across this region, especially to the east of the Mojave segment of the San Andreas in a region known as the eastern California shear zone (ECSZ), was highlighted by the occurrence (on 28 June 1992) of the magnitude 7.3 Landers earthquake in this zone. Here we use geodetic observations in the central Mojave desert to obtain new estimates for the rate and distribution of strain across a segment of the ECSZ, and to determine a coseismic strain drop of approximately 770 murad for the Landers earthquake. From these results we infer a strain energy recharge time of 3,500-5,000 yr for a Landers-type earthquake and a slip rate of approximately 12 mm yr-1 across the faults of the central Mojave. The latter estimate implies that a greater fraction of plate motion than heretofore inferred from geodetic data is accommodated across the ECSZ.
C1 US GEOL SURVEY,MENLO PK,CA 94025.
   CARNEGIE INST WASHINGTON,DEPT TERR MAGNETISM,WASHINGTON,DC 20015.
C3 United States Department of the Interior; United States Geological Survey; Carnegie Institution for Science
RP SAUBER, J (corresponding author), NASA,GODDARD SPACE FLIGHT CTR,GEODYNAM BRANCH,TERR PHYS LAB,GREENBELT,MD 20771, USA.
NR 28
TC 134
Z9 153
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 264
EP 266
DI 10.1038/367264a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400053
DA 2026-03-10
ER

PT J
AU GUERRET-PIECOURT, C
   LEBOUAR, Y
   LOISEAU, A
   PASCARD, H
AF GUERRET-PIECOURT, C
   LEBOUAR, Y
   LOISEAU, A
   PASCARD, H
TI RELATION BETWEEN METAL ELECTRONIC-STRUCTURE AND MORPHOLOGY OF METAL-COMPOUNDS INSIDE CARBON NANOTUBES
SO NATURE
LA English
DT Article
ID filamentous carbon; yttrium
AB SEVERAL attempts have been made to fill carbon nanotubes(1) with metals or metallic compounds to obtain nanocomposite materials with potentially interesting properties. Capillary action, predicted(2) to be a filling mechanism, has been used(3,4) to encapsulate lead and bismuth in open tubes. Compounds of yttrium(5), manganese(6) and gadolinium(7) have also been encapsulated by formation of the nanotubes in an are discharge with the metals present in situ. Very recently, Tsang et al.(8) showed that oxides of nickel, cobalt, iron and uranium can be encapsulated by opening the tubes and depositing the filling material using wet chemical techniques. Here we report a search for general principles relating to the nature and structure of the filling material, using the are-discharge method to fill tubes with fifteen metals and/or their compounds: Ti, Cr, Fe, Co, Ni, Cu, Zn, Mo, Pd, Sn, Ta, W, Gd, Dy and Yb. We find that the propensity for forming continuous 'nanowires' throughout the length of the tubes seems to be strongly correlated with the existence of an incomplete electronic shell in the most stable ionic state of the metal. We also find that the interplay between growth of the nanotube and growth of the filling results, in one case, in the formation of an unusual helical filling morphology.
C1 ECOLE POLYTECH, CEA, SOLIDES IRRADIES LAB, CNRS, F-91128 PALAISEAU, FRANCE.
   OFF NATL ETUD & RECH AEROSP, LAB PHYS SOLIDE, F-92322 CHATILLON, FRANCE.
C3 Institut Polytechnique de Paris; Ecole Polytechnique; CEA; Centre National de la Recherche Scientifique (CNRS); Universite Paris Saclay; National Office for Aerospace Studies & Research (ONERA)
NR 16
TC 468
Z9 507
U1 0
U2 146
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 761
EP 765
DI 10.1038/372761a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200047
DA 2026-03-10
ER

PT J
AU PANTALEO, G
   DEMAREST, JF
   SOUDEYNS, H
   GRAZIOSI, C
   DENIS, F
   ADELSBERGER, JW
   BORROW, P
   SAAG, MS
   SHAW, GM
   SEKALY, RP
   FAUCI, AS
AF PANTALEO, G
   DEMAREST, JF
   SOUDEYNS, H
   GRAZIOSI, C
   DENIS, F
   ADELSBERGER, JW
   BORROW, P
   SAAG, MS
   SHAW, GM
   SEKALY, RP
   FAUCI, AS
TI MAJOR EXPANSION OF CD8+ T-CELLS WITH A PREDOMINANT V-BETA USAGE DURING THE PRIMARY IMMUNE-RESPONSE TO HIV
SO NATURE
LA English
DT Article
ID immunodeficiency-virus type-1; variable region genes; cd8+ lymphocytes-t; vaccinia virus; expression vector; infection; chain; recognition; sequences; diversity
AB A SIGNIFICANT proportion (up to 70%) of individuals experience an acute clinical syndrome of varying severity associated with primary infection with the human immunodeficiency virus (HIV)(1-4). We report here studies on six individuals who showed an acute HIV syndrome which generally resolved within four weeks, concomitant with a dramatic downregulation of viraemia(2-5). To characterize the T-cell-mediated primary immune response to HIV, we used combined semiquantitative polymerase chain reaction assay and cytofluorometry to analyse the T-cell antigen receptor repertoire in sequential peripheral blood mononuclear cells from the patients. We found major oligoclonal expansions in a restricted set of variable-domain beta-chain (V beta) families. Cells expressing the expanded V beta s predominantly expressed the CD8 T-cell differentiation antigen and mediated HIV-specific cytotoxicity. Major oligoclonal expansions of these CD8(+) T lymphocytes may represent an important component of the primary immune response to viral infections and may help to clarify both the immunopathogenic and the protective mechanisms of HIV infection.
C1 INST RECH CLIN MONTREAL, IMMUNOL LAB, MONTREAL H2W 1R7, PQ, CANADA.
   PROGRAM RESOURCES INC DYNCORP, FREDERICK, MD 21702 USA.
   UNIV ALABAMA, DEPT MED, BIRMINGHAM, AL 35294 USA.
   Scripps Res Inst, DEPT NEUROPHARMACOL, DIV VIROL, LA JOLLA, CA 92037 USA.
   UNIV MONTREAL, DEPT MICROBIOL & IMMUNOL, MONTREAL H3C 3J7, PQ, CANADA.
   MCGILL UNIV, DEPT MICROBIOL & IMMUNOL, MONTREAL H3A 2B4, PQ, CANADA.
C3 Institut de Recherche Clinique de Montreal (IRCM); Universite de Montreal; University of Alabama System; University of Alabama Birmingham; Scripps Research Institute; Universite de Montreal; McGill University
RP PANTALEO, G (corresponding author), NIAID, IMMUNOREGULAT LAB, BETHESDA, MD 20892 USA.
NR 26
TC 571
Z9 635
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 463
EP 467
DI 10.1038/370463a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700057
PM 8047166
DA 2026-03-10
ER

PT J
AU WHITE, JWC
   CIAIS, P
   FIGGE, RA
   KENNY, R
   MARKGRAF, V
AF WHITE, JWC
   CIAIS, P
   FIGGE, RA
   KENNY, R
   MARKGRAF, V
TI A HIGH-RESOLUTION RECORD OF ATMOSPHERIC CO2 CONTENT FROM CARBON ISOTOPES IN PEAT
SO NATURE
LA English
DT Article
ID non-exchangeable hydrogen; past 2 century; ice core; polar ice; discrimination; photosynthesis; respiration; bryophytes; cellulose; dioxide
AB OUR understanding of how future changes in atmospheric carbon-dioxide concentrations will affect the global climate system arises in part from comparing past changes in climate and CO2. To date, these comparisons have come mainly from ice-core data, which show a strong correlation-between past atmospheric CO2 concentration and polar temperature1. Here we present a new method for reconstructing atmospheric CO2 concentration using the C-13/C-12 ratio (deltaC-13) in mosses and sedges in peat. Our method exploits the fact that, unlike sedges and most other plants, mosses do not possess stomata, and are therefore unable to regulate their uptake of CO2 and water. The deltaC-13 of mosses thus depends on both atmospheric CO2 concentration and available water, and the of sedges from the same peat can be used to remove the water signal. The method provides a resolution of about a decade much higher than is possible from ice cores. We present initial results for the past 14,000 years, which show three sharp increases in atmospheric CO2 concentration: at 12,800 years ago, corresponding to an episode of warming in the North Atlantic region, 10,000 years ago, corresponding to the end of the Younger Dryas cold period; and 4,400 years ago, after which time modern climates were established globally.
C1 UNIV COLORADO, DEPT GEOL SCI, BOULDER, CO 80309 USA.
   NOAA, CMDL, BOULDER, CO 80303 USA.
C3 University of Colorado System; University of Colorado Boulder; National Oceanic Atmospheric Admin (NOAA) - USA
RP WHITE, JWC (corresponding author), UNIV COLORADO, INST ARCTIC & ALPINE RES, CAMPUS BOX 450, BOULDER, CO 80309 USA.
NR 34
TC 128
Z9 151
U1 1
U2 22
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 153
EP 156
DI 10.1038/367153a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000054
DA 2026-03-10
ER

PT J
AU HASHIMOTO, L
   HABITA, C
   BERESSI, JP
   DELEPINE, M
   BESSE, C
   CAMBONTHOMSEN, A
   DESCHAMPS, I
   ROTTER, JI
   DJOULAH, S
   JAMES, MR
   FROGUEL, P
   WEISSENBACH, J
   LATHROP, GM
   JULIER, C
AF HASHIMOTO, L
   HABITA, C
   BERESSI, JP
   DELEPINE, M
   BESSE, C
   CAMBONTHOMSEN, A
   DESCHAMPS, I
   ROTTER, JI
   DJOULAH, S
   JAMES, MR
   FROGUEL, P
   WEISSENBACH, J
   LATHROP, GM
   JULIER, C
TI GENETIC-MAPPING OF A SUSCEPTIBILITY LOCUS FOR INSULIN-DEPENDENT DIABETES-MELLITUS ON CHROMOSOME 11Q
SO NATURE
LA English
DT Article
ID region; marker
AB LOCI in the major histocompatibility complex (MHC) on chromosome 6 and the insulin (INS) region on chromosome 11 have been implicated in susceptibility to insulin-dependent diabetes mellitus (IDDM) through candidate gene investigations(1-5), but they may account for less than 50% of genetic risk for the disease(6). Genome-wide linkage studies have led to localization of more than 10 susceptibility loci for insulin-dependent diabetes in the non-obese diabetic (NOD) mouse(7) and the BB rat(8). Similar studies are now possible in humans through the development of dense genetic maps of highly informative microsatellite loci obtained using polymerase chain reaction analysis(9). We have applied microsatellite markers from recent Genethon maps(10,11), and other highly informative markers, in a genome-wide linkage study in IDDM. Here we report evidence for the localization of a previously undetected susceptibility locus for IDDM in the region of the FGF3 gene on chromosome 11q. Our result shows the potential of genome-wide linkage studies to detect susceptibility loci in IDDM and other multifactorial disorders.
C1 WELLCOME TRUST CTR HUMAN GENET, OXFORD OX3 7BN, ENGLAND.
   HOP ST LOUIS, INSERM, U93, F-75010 PARIS, FRANCE.
   CTR ETUD POLYMORPHISME HUMAIN, F-75010 PARIS, FRANCE.
   HOP PURPAN, CTR IMMUNOPATHOL & GENET HUMAINE, CNRS, UPR 8291, F-31300 TOULOUSE, FRANCE.
   HOP NECKER ENFANTS MALAD, SERV ENDOCRINOL & DIABET ENFANT, F-75015 PARIS, FRANCE.
   CEDARS SINAI MED CTR, DIV MED GENET, LOS ANGELES, CA 90048 USA.
   UNIV CALIF LOS ANGELES, SCH MED, LOS ANGELES, CA 90048 USA.
   GENETHON, F-91002 EVRY, FRANCE.
   HOP ST LOUIS, SERV ENDOCRINOL, F-75010 PARIS, FRANCE.
C3 University of Oxford; Wellcome Centre for Human Genetics; Institut National de la Sante et de la Recherche Medicale (Inserm); Assistance Publique Hopitaux Paris (APHP); Universite Paris Cite; Hopital Universitaire Saint-Louis - APHP; Centre National de la Recherche Scientifique (CNRS); Universite de Toulouse; Universite Toulouse III - Paul Sabatier; CHU de Toulouse; Assistance Publique Hopitaux Paris (APHP); Universite Paris Cite; Hopital Universitaire Necker-Enfants Malades - APHP; Cedars Sinai Medical Center; University of California System; University of California Los Angeles; University of California Los Angeles Medical Center; David Geffen School of Medicine at UCLA; Universite Paris Cite; Assistance Publique Hopitaux Paris (APHP); Hopital Universitaire Saint-Louis - APHP
RP JULIER, C (corresponding author), HOP ST LOUIS, INSERM, U358, Batiment INSERM,12 Rue Grange Aux Belles, F-75010 PARIS, FRANCE.
FU Wellcome Trust Funding Source: Medline
NR 22
TC 384
Z9 407
U1 2
U2 11
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 161
EP 164
DI 10.1038/371161a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100065
PM 8072544
DA 2026-03-10
ER

PT J
AU GUZDER, SN
   QIU, HF
   SOMMERS, CH
   SUNG, P
   PRAKASH, L
   PRAKASH, S
AF GUZDER, SN
   QIU, HF
   SOMMERS, CH
   SUNG, P
   PRAKASH, L
   PRAKASH, S
TI DNA-REPAIR GENE RAD3 OF SACCHAROMYCES-CEREVISIAE IS ESSENTIAL FOR TRANSCRIPTION BY RNA POLYMERASE-II
SO NATURE
LA English
DT Article
ID saccharomyces-cerevisiae; xeroderma-pigmentosum; nucleotide-sequence; dependent atpase; yeast homolog; initiation; requirement; helicase; protein; encodes
AB THE RAD3 gene of Saccharomyces cerevisiae is required for excision repair of ultraviolet-damaged DNA and is essential for cell viability1. The RAD3-encoded protein shares a high degree of homology with the human ERCC2(XPD) gene product2. Mutations in XPD, besides causing the cancer-prone syndrome xeroderma pigmentosum, can also result in Cockayne's syndrome and trichothiodystrophy3. To investigate the role of RAD3 in viability, we examine here the effect of a recessive, temperature-sensitive (ts) conditional lethal mutation of the gene on transcription by RNA polymerase II. Upon transfer to the restrictive temperature, the rad3-ts mutant rapidly ceases growth and poly(A)+ RNA synthesis is inhibited drastically.  Messenger RNA levels of all the genes examined, HIS3, TRP3, STE2, MET19, RAD23, CDC7, CDC9 and ACT1, decline rapidly upon loss of RAD3 activity.  The synthesis of heat-shock-inducible HSP26 mRNA and galactose-inducible GAL7 and GAL10 mRNAs is also drastically inhibited in the rad3-ts mutant at the restrictive temperature. The RNA polymerase II transcriptional activity in extract from the rad3-ts14 strain is thermolabile, and this in vitro transcriptional defect can be fully corrected by the addition of homogeneous RAD3 protein. These findings indicate that RAD3 protein has a direct and essential role in RNA polymerase II transcription.
C1 UNIV ROCHESTER,DEPT BIOL,ROCHESTER,NY 14642.
   UNIV ROCHESTER,DEPT BIOPHYS,ROCHESTER,NY 14642.
   UNIV TEXAS,MED BRANCH,SEALY CTR MOLEC SCI,GALVESTON,TX 77555.
C3 University of Rochester; University of Rochester; University of Texas System; University of Texas Medical Branch Galveston
NR 30
TC 137
Z9 144
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 91
EP 94
DI 10.1038/367091a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500067
PM 8107780
DA 2026-03-10
ER

PT J
AU KHALIL, MAK
   RASMUSSEN, RA
AF KHALIL, MAK
   RASMUSSEN, RA
TI GLOBAL DECREASE IN ATMOSPHERIC CARBON-MONOXIDE CONCENTRATION
SO NATURE
LA English
DT Article
ID earths atmosphere; methane; trends; ch4
AB CARBON monoxide plays an important role in the oxidizing capacity of the Earth's atmosphere, and may thereby indirectly affect the concentrations of many man-made and natural trace gases, which in turn affect climate, atmospheric chemistry and the ozone layer(1). CO is produced in the atmosphere by the oxidation of methane and other hydrocarbons, and is released into the atmosphere from automobiles, agricultural waste and the burning of savanna(1-4). Recent estimates' show that human activities such as these are presently responsible for more than half the annual emissions of CO. During the 1980s there was evidence that atmospheric CO concentrations were increasing at similar to 1.2 +/- 0.6% per year, leading to feedbacks that could amplify global warming. Here we present a continuation of these measurements which show that from 1988 to 1992 global CO concentrations have started to decline rapidly at a rate of about -2.6 +/- 0.8% per gear. A recent study(5) has verified our findings with data from the past 3-4 years. The rate of decrease is particularly rapid in the Southern Hemisphere; we hypothesize that this mag reflect a reduction in tropical biomass burning. The total amount of carbon monoxide in the atmosphere is less now than a decade ago.
C1 OREGON GRAD INST,DEPT ENVIRONM SCI & ENGN,BEAVERTON,OR 97006.
RP KHALIL, MAK (corresponding author), OREGON GRAD INST,GLOBAL CHANGE RES CTR,BEAVERTON,OR 97006, USA.
NR 18
TC 118
Z9 133
U1 1
U2 24
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 639
EP 641
DI 10.1038/370639a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000046
DA 2026-03-10
ER

PT J
AU NEHLS, M
   PFEIFER, D
   SCHORPP, M
   HEDRICH, H
   BOEHM, T
AF NEHLS, M
   PFEIFER, D
   SCHORPP, M
   HEDRICH, H
   BOEHM, T
TI NEW MEMBER OF THE WINGED-HELIX PROTEIN FAMILY DISRUPTED IN MOUSE AND RAT NUDE MUTATIONS
SO NATURE
LA English
DT Article
ID gene fork-head; transcription factors; embryo; thymus; domain; mice
AB MUTATIONS at the nude locus of mice and rats disrupt normal hair growth and thymus development(1,2), causing nude mice and rats to be immune-deficient. The mouse nude locus has been localized on chromosome 11 (refs 3, 4) within a region of <1 megabase(5). Here we show that one of the genes from this critical region, designated whn, encodes a new member of the winged-helix domain family of transcription factors(6.7), and that it is disrupted on mouse au and rat rnuN alleles. Mutant transcripts do not encode the characteristic DNA-binding domain, strongly suggesting that the whn gene is the nude gene. Mutations in winged-helix domain genes cause homeotic transformations in Drosophila(8) and distort cell-fate decisions during vulval development in Caenorhabditis elegans(9). The whn gene is thus the first member of this class of genes to be implicated in a specific developmental defect in vertebrates.
C1 HANNOVER MED SCH,ZENT TIERVERSUCHSANLAGE,D-30625 HANNOVER,GERMANY.
   UNIV FREIBURG,DEPT MED 1,MOLEC MED GRP,D-79106 FREIBURG,GERMANY.
C3 Hannover Medical School; University of Freiburg
NR 21
TC 570
Z9 645
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 103
EP 107
DI 10.1038/372103a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800083
PM 7969402
DA 2026-03-10
ER

PT J
AU KAHN, JD
   YUN, E
   CROTHERS, DM
AF KAHN, JD
   YUN, E
   CROTHERS, DM
TI DETECTION OF LOCALIZED DNA FLEXIBILITY
SO NATURE
LA English
DT Article
ID escherichia-coli; ring-closure; gel-electrophoresis; bend direction; protein hu; cyclization; replication; simulation; origin; model
AB THE bending and flexibility of DNA are important in packaging, recombination and transcription(1-3). Bending decreases electrophoretic mobility in a manner depending on bend position within a fragment (circular permutation(4)) and on the distance between bends (phasing analysis(5,6)). Bending can also affect DNA ring closure (cyclization(7-10)). The lack of a complete theory for the mechanism of gel retardation hampers measurement of bend magnitudes by electrophoresis, whereas cyclization is done entirely in solution and is well understood theoretically(9). Disagreements between bend angles estimated by the two electrophoretic assays have been ascribed to DNA flexibility(11). Here we test this interpretation using an internal loop as a model flexible locus. Whereas the circular permutation and helical phasing experiments are only subtly affected by the loop, DNA cyclization kinetics detects and quantifies substantial increases in torsional and bending flexibility. Furthermore, the results support a functional role for the stress of DNA bending in inducing base-pair opening(12).
C1 YALE UNIV,DEPT CHEM,NEW HAVEN,CT 06511.
   YALE UNIV,DEPT MOLEC BIOPHYS & BIOCHEM,NEW HAVEN,CT 06511.
C3 Yale University; Yale University
NR 30
TC 181
Z9 199
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 163
EP 166
DI 10.1038/368163a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000071
PM 8139661
DA 2026-03-10
ER

PT J
AU YAPP, CJ
   POTHS, H
AF YAPP, CJ
   POTHS, H
TI PRODUCTIVITY OF PRE-VASCULAR CONTINENTAL BIOTA INFERRED FROM THE FE(CO3)OH CONTENT OF GOETHITE
SO NATURE
LA English
DT Article
ID carbon-dioxide; atmospheric co2; isotopic composition; phanerozoic time; late ordovician; cycle; land; pressures; climate; plants
AB CHEMICAL weathering of rocks bysCO(2)-an important process in the carbon cycle-may have been affected by the appearance of vascular plants during the Silurian period (438-408 Myr ago), because of the enhanced efficacy of these plants in promoting weathering(1). The magnitude of this effect is uncertain, however(2-4). One key issue is the concentration of CO2 in soils, generated by microbial respiration; this is itself in part a function of soil productivity. We showed recently(5) that the CO2 partial pressure in a Late Ordovician soil was 5.6 times that in the atmosphere; Keller and Wood(6) have shown, however, that soil CO2 concentrations can be high even for low levels of microbial respiration, as a result of slow diffusion of respired CO2 out of the Soil. Here we present an analysis of the Fe(CO3)OH component of goethite (FeOOH) in an Upper Ordovician oolitic ironstone which underwent tropical chemical weathering 440 Myr ago(7,8). These data allow us to extract an estimate of the CO2 flux from the soil profile. The high rate that we obtain implies that the productivity of pre-vascular biota was similar to that in modern soils. Thus, attempts to model atmospheric CO2 concentrations over Phanerozoic(9-12) time need not assume that pronounced productivity changes accompanied the development of vascular plants.
RP YAPP, CJ (corresponding author), UNIV NEW MEXICO,DEPT EARTH & PLANETARY SCI,ALBUQUERQUE,NM 87131, USA.
NR 31
TC 31
Z9 32
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 49
EP 51
DI 10.1038/368049a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900048
DA 2026-03-10
ER

PT J
AU ESGUERRA, M
   WANG, J
   FOSTER, CD
   ADELMAN, JP
   NORTH, RA
   LEVITAN, IB
AF ESGUERRA, M
   WANG, J
   FOSTER, CD
   ADELMAN, JP
   NORTH, RA
   LEVITAN, IB
TI CLONED CA2+-DEPENDENT K+ CHANNEL MODULATED BY A FUNCTIONALLY ASSOCIATED PROTEIN-KINASE
SO NATURE
LA English
DT Article
ID activated potassium channels; phosphorylation; camp; brain; dephosphorylation; cells
AB CALCIUM-DEPENDENT potassium (K-Ca) channels carry ionic currents that regulate important cellular functions(1-3). Like some other ion channels(4-10), K-Ca channels are modulated by protein phosphorylation(2,11,15-21). The recent cloning of complementary DNAs encoding Slo K-Ca channels(12-14) has enabled K-Ca channel modulation to be investigated. We report here that protein phosphorylation modulates the activity of Drosophila Slo K-Ca channels expressed in Xenopus oocytes. Application of ATP-gamma S to detached membrane patches increases Slo channel activity by shifting channel voltage sensitivity. This modulation is blocked by a specific inhibitor of cyclic AMP-dependent protein kinase (PKA). Mutation of a single serine residue in the channel protein also blocks modulation by ATP-gamma S, demonstrating that phosphorylation of the Slo channel protein itself modulates channel activity. The results also indicate that K-Ca channels in oocyte membrane patches can be modulated by an endogenous PKA-like protein kinase which remains functionally associated with the channels in the detached patch.
C1 BRANDEIS UNIV,DEPT BIOCHEM,WALTHAM,MA 02254.
   BRANDEIS UNIV,CTR COMPLEX SYST,WALTHAM,MA 02254.
   OREGON HLTH SCI UNIV,VOLLUM INST,PORTLAND,OR 97201.
C3 Brandeis University; Brandeis University; Oregon Health & Science University
NR 29
TC 102
Z9 108
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 563
EP 565
DI 10.1038/369563a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400050
PM 8202157
DA 2026-03-10
ER

PT J
AU UMEMORI, H
   SATO, S
   YAGI, T
   AIZAWA, S
   YAMAMOTO, T
AF UMEMORI, H
   SATO, S
   YAGI, T
   AIZAWA, S
   YAMAMOTO, T
TI INITIAL EVENTS OF MYELINATION INVOLVE FYN TYROSINE KINASE SIGNALING
SO NATURE
LA English
DT Article
ID cell antigen receptor; src protein; terminal region; glycoprotein; association; family; adhesion; brain; expression; efficient
AB MYELIN is the lipoprotein multimembrane that functions as an insulator preventing the flow of ion currents across the axonal membrane and facilitating the conduction of nerve impulses. It is synthesized by oligodendrocytes in the central nervous system at about the time of birth in mammals1. During the initial stages of myelination, several proteins are phosphorylated on tyrosine. Among these proteins, we identified Fyn tyrosine kinase, one of the non-receptor-type tyrosine kinases of the Src family. Here we report that Fyn tyrosine kinase is activated during the initial stages of myelination and that it is associated with the large myelin-associated glycoprotein (MAG), an adhesion molecule that has been implicated in myelinogenesis2. The Fyn-large MAG association requires amino-terminal domains of Fyn that include SH2 and SH3 (Src homology domains 2 and 3). Crosslinking of large MAG with antibody induces a rapid increase in the specific activity of Fyn kinase. These results indicate that Fyn participates in the initial events of myelination as a signalling molecule downstream of large MAG; indeed, we find that fyn-deficient mice exhibit impaired myelination.
C1 UNIV TOKYO,INST MED SCI,DEPT ONCOL,4-6-1 SHIROKANEDAI,MINATO KU,TOKYO 108,JAPAN.
   NIIGATA UNIV,BRAIN RES INST,DEPT NEUROL,NIIGATA 951,JAPAN.
   INST PHYS & CHEM RES,TSUKUBA LIFE SCI CTR,MOLEC ONCOL LAB,TSUKUBA,IBARAKI 305,JAPAN.
C3 University of Tokyo; Niigata University; RIKEN
NR 30
TC 353
Z9 401
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 572
EP 576
DI 10.1038/367572a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300063
PM 7509042
DA 2026-03-10
ER

PT J
AU VIDGREN, J
   SVENSSON, LA
   LILJAS, A
AF VIDGREN, J
   SVENSSON, LA
   LILJAS, A
TI CRYSTAL-STRUCTURE OF CATECHOL O-METHYLTRANSFERASE
SO NATURE
LA English
DT Article
ID rat-liver; parkinsons-disease; methylation; inhibition; binding; purification; cloning; or-462; models; site
AB CATECHOL O-methyltransferase (COMT, EC 2.1.1.6) is important in the central nervous system because it metabolizes catecholamine neurotransmitters such as dopamine. The enzyme catalyses the transfer of the methyl group from S-adenosyl-L-methionine (AdoMet) to one hydroxyl group of catechols(1-4). COMT also inactivates catechol-type compounds such as L-DOPA. With selective inhibitors of COMT in combination with L-DOPA, a new principle has been realized in the therapy of Parkinson's disease(5-9). Here we solve the atomic structure of COMT to 2.0 Angstrom resolution, which provides new insights into the mechanism of the methyl transfer reaction. The co-enzyme-binding domain is strikingly similar to that of an AdoMet-dependent DNA methylase(10), indicating that all AdoMet methylases may have a common structure.
C1 LUND UNIV,CTR CHEM,S-22100 LUND,SWEDEN.
C3 Lund University
RP VIDGREN, J (corresponding author), ORION CORP,ORION FARMOS,POB 65,SF-02101 ESPOO,FINLAND.
NR 29
TC 394
Z9 441
U1 0
U2 62
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 354
EP 358
DI 10.1038/368354a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500052
PM 8127373
DA 2026-03-10
ER

PT J
AU SAHAGIAN, DL
   MAUS, JE
AF SAHAGIAN, DL
   MAUS, JE
TI BASALT VESICULARITY AS A MEASURE OF ATMOSPHERIC-PRESSURE AND PALAEOELEVATION
SO NATURE
LA English
DT Article
ID cretaceous shoreline deposits; climate; uplift; coalescence; colorado; flows
AB The pressure in, and thus the size of, a bubble in a lava flow is determined by the atmospheric pressure and the hydrostatic pressure of the overlying lava. If atmospheric sea-level pressure is known (or assumed), vesicle size distributions in basalt flows can thus be used as an indicator of the palaeoelevation of emplacement(1). Here we show by analysis of the vesicle size distribution of basalt samples collected from the summit and base of Mauna Loa volcano in Hawaii that the technique provides estimates of ambient pressure that are accurate to within 0.1 bar, and thus estimates of elevation with a resolution of about 1,400 m. This palaeoaltimetric technique should find useful application in palaeogeographical reconstruction(2) for times when sea-level pressure was similar to the present value. (Conversely, if the elevation of emplacement is known, our technique should be able to provide a measure of sea-level palaeopressure.) Unlike palaeobotanical methods for estimating elevations(3-6), this method does not have to assume a relationship between temperature and altitude; on the other hand, its use is restricted to lava flows that have had a simple emplacement history.
C1 OHIO STATE UNIV,DEPT GEOL SCI,COLUMBUS,OH 43210.
C3 University System of Ohio; Ohio State University
RP SAHAGIAN, DL (corresponding author), UNIV NEW HAMPSHIRE,INST STUDY EARTH OCEANS & SPACE,DURHAM,NH 03824, USA.
NR 21
TC 57
Z9 79
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 449
EP 451
DI 10.1038/372449a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200052
DA 2026-03-10
ER

PT J
AU PARTHASARATHY, RV
   MARTIN, CR
AF PARTHASARATHY, RV
   MARTIN, CR
TI SYNTHESIS OF POLYMERIC MICROCAPSULE ARRAYS AND THEIR USE FOR ENZYME IMMOBILIZATION
SO NATURE
LA English
DT Article
ID glucose-oxidase; template synthesis; covalent electropolymerization; electronic conductivity; polypyrrole films; microtubules; sensors
AB CURRENT methods for immobilizing enzymes for use in bioreactors and biosensors(1-20) include adsorption on or covalent attachment to a support(2-4), micro-encapsulation(5,6), and entrapment within a membrane/film(7,8,11-20) or gel(9). The ideal immobilization method should employ mild chemical conditions, allow for large quantities of enzyme to be immobilized, provide a large surface area for enzyme-substrate contact within a small total volume, minimize barriers to mass transport of substrate and product, and provide a chemically and mechanically robust system. Here we describe a method for enzyme immobilization that satisfies all of these criteria. We have developed a template-based synthetic method that yields hollow polymeric microcapsules of uniform diameter and length. These microcapsules are arranged in a high-density array in which the individual capsules protrude from a surface like the bristles of a brush. We have developed procedures for filling these microcapsules with high concentrations of enzymes. The enzyme-loaded microcapsule arrays function as enzymatic bioreactors in both aqueous solution and organic solvents.
C1 COLORADO STATE UNIV,DEPT CHEM,FT COLLINS,CO 80523.
C3 Colorado State University System; Colorado State University Fort Collins
NR 34
TC 332
Z9 376
U1 1
U2 199
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 298
EP 301
DI 10.1038/369298a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900042
PM 8183367
DA 2026-03-10
ER

PT J
AU STARK, MR
   JOHNSON, AD
AF STARK, MR
   JOHNSON, AD
TI INTERACTION BETWEEN 2 HOMEODOMAIN PROTEINS IS SPECIFIED BY A SHORT C-TERMINAL TAIL
SO NATURE
LA English
DT Article
ID homeo domain; alpha-2 repressor; crystal-structure; dna interactions; mcm1 protein; yeast a1; binding; operator; polymerase; complex
AB TWO yeast homeodomain proteins, a1 and alpha 2, interact and cooperatively bind the haploid-specific gene (Hsg) operator, resulting in the repression of a set of genes involved in the determination of cell type(1-5). The cooperative binding of a1 and alpha 2 to DNA can be reconstituted in vitro using purified fragments of a1 and alpha 2. Only the homeodomain is needed for a1, but for alpha 2 a C-terminal 22-amino-acid tail is required as well(4,6-9). As most of the specificity of DNA binding appears to derive from a1, we proposed(4) that alpha 2 functions in the a1/alpha 2 heterodimer to contact a1 with its tail. By construction and analysis of several chimaeric proteins, we investigate how two DNA-binding proteins, one with low intrinsic specificity (alpha 2) and one with no apparent intrinsic DNA-binding ability (a1), can together create a highly specific DNA-binding activity(4). We show that the 22-amino-acid region of alpha 2 immediately C-terminal to the homeodomain, when grafted onto the a1 homeodomain, converts a1 to a strong DNA-binding protein. This alpha 2 tail can also be attached to the Drosophila engrailed homeodomain, and the chimaeric protein now binds cooperatively to DNA with a1, showing how a simple change can create a new homeodomain combination that specifically recognizes a new DNA operator.
C1 UNIV CALIF SAN FRANCISCO,SCH MED,DEPT IMMUNOL & MICROBIOL,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco
RP STARK, MR (corresponding author), UNIV CALIF SAN FRANCISCO,SCH MED,DEPT BIOCHEM & BIOPHYS,SAN FRANCISCO,CA 94143, USA.
NR 23
TC 60
Z9 64
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 429
EP 432
DI 10.1038/371429a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500046
PM 8090224
DA 2026-03-10
ER

PT J
AU SLATIN, SL
   QIU, XQ
   JAKES, KS
   FINKELSTEIN, A
AF SLATIN, SL
   QIU, XQ
   JAKES, KS
   FINKELSTEIN, A
TI IDENTIFICATION OF A TRANSLOCATED PROTEIN SEGMENT IN A VOLTAGE-DEPENDENT CHANNEL
SO NATURE
LA English
DT Article
ID colicin-e1 ion channel; planar lipid bilayers; helical hairpin; membrane; topography
AB VOLTAGE-GATED channels undergo a conformational change in response to changes in transmembrane voltage. Here we use site-directed biotinylation to create conformation-sensitive sites on colicin Ia, a bacteriocidal protein that forms a voltage-sensitive membrane channel, which can be monitored by electrophysiological methods(1,2). We investigated a model of gating developed for the partly homologous colicin E1 that is based on the insertion of regions of the protein into the membrane in response to cis-positive voltages(3-6). Site-directed cysteine mutagenesis, followed by chemical modification, was used to attach a biotin molecule covalently to a series of unique sites on colicin Ia. The modified protein was incorporated into planar lipid membranes, where the introduced biotin moiety served as a site to bind the water-soluble protein streptavidin, added to one side of the membrane or the other. Our results show that colicin gating is associated with the translocation across the membrane of a segment of the protein of at least 31 amino acids.
RP SLATIN, SL (corresponding author), YESHIVA UNIV ALBERT EINSTEIN COLL MED,DEPT PHYSIOL & BIOPHYS,BRONX,NY 10461, USA.
NR 19
TC 153
Z9 162
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 158
EP 161
DI 10.1038/371158a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100064
PM 7521016
DA 2026-03-10
ER

PT J
AU STEPHENS, PW
   BORTEL, G
   FAIGEL, G
   TEGZE, M
   JANOSSY, A
   PEKKER, S
   OSZLANYI, G
   FORRO, L
AF STEPHENS, PW
   BORTEL, G
   FAIGEL, G
   TEGZE, M
   JANOSSY, A
   PEKKER, S
   OSZLANYI, G
   FORRO, L
TI POLYMERIC FULLERENE CHAINS IN RBC60 AND KC60
SO NATURE
LA English
DT Article
AB NEARLY all of the molecular crystals containing C-60 formed at ambient pressure(1,2) have inter-fullerene separations of the order of 10 Angstrom-the expected distance based on the molecular van der Waals radii. The sole exceptions are the room-temperature phases of AC(60) (where A denotes K, Rb or Cs), which are formed by reversible solid-state transformation from high-temperature (> 150 degrees C) phases(3). These phases have lattice parameters about 9% shorter in one direction, and in addition RbC60 has magnetic properties suggestive of a one-dimensional metal(4). We suggested in ref. 4 that this short distance may be due to covalent bonding between neighbouring C-60 molecules. Here we provide direct evidence for such bonding from powder X-ray diffraction studies of RbC60, and KC60. The linkage is through a [2 + 2] cycloaddition, which has been hypothesized to take place during photopolymerization of solid C-60 (ref. 5), and which has also been proposed(6) for RbC60. Such inter-fullerene linkages are calculated(7,8) to be the preferred mode of dimerization of C-60. The AC(60) phases thus provide an example of a thermal phase transition driven by the reversible formation and breaking of covalent bonds.
C1 HUNGARIAN ACAD SCI,SOLID STATE PHYS RES INST,H-1525 BUDAPEST,HUNGARY.
   TECH UNIV BUDAPEST,INST PHYS,H-1521 BUDAPEST,HUNGARY.
   ECOLE POLYTECH FED LAUSANNE,INST GENIE ATOM,DEPT PHYS,PHYS SOLIDES SEMICRYSTALLINS LAB,CH-1015 LAUSANNE,SWITZERLAND.
C3 Hungarian Academy of Sciences; HUN-REN; HUN-REN Wigner Research Centre for Physics; Institute for Solid State Physics & Optics - HAS; Budapest University of Technology & Economics; Swiss Federal Institutes of Technology Domain; Ecole Polytechnique Federale de Lausanne
RP STEPHENS, PW (corresponding author), SUNY STONY BROOK,DEPT PHYS,STONY BROOK,NY 11794, USA.
NR 17
TC 532
Z9 539
U1 2
U2 52
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 636
EP 639
DI 10.1038/370636a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000045
DA 2026-03-10
ER

PT J
AU LI, YZ
   HUNTER, RL
   MCIVER, RT
AF LI, YZ
   HUNTER, RL
   MCIVER, RT
TI HIGH-RESOLUTION MASS-SPECTROMETER FOR PROTEIN CHEMISTRY
SO NATURE
LA English
DT Article
ID assisted laser-desorption; ion-cyclotron resonance; biological molecules; sequence databases; matrix; peptides; spectroscopy; field
AB Matrix-assisted laser desorption/ionization is an accurate and sensitive method for measuring the molecular weights of peptides and proteins. Usually time-of-flight mass spectrometry is used to detect the laser-produced ions, but a new method called Fourier transform mass spectrometry offers greater sensitivity and much higher mass measurement accuracy.
C1 IONSPEC CORP,IRVINE,CA 92714.
RP LI, YZ (corresponding author), UNIV CALIF IRVINE,DEPT CHEM,IRVINE,CA 92717, USA.
NR 35
TC 11
Z9 11
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 393
EP 395
DI 10.1038/370393a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400066
PM 8047148
DA 2026-03-10
ER

PT J
AU MERINEY, SD
   GRAY, DB
   PILAR, GR
AF MERINEY, SD
   GRAY, DB
   PILAR, GR
TI SOMATOSTATIN-INDUCED INHIBITION OF NEURONAL CA2+ CURRENT MODULATED BY CGMP-DEPENDENT PROTEIN-KINASE
SO NATURE
LA English
DT Article
ID rat sympathetic neurons; chick sensory neurons; calcium current; ganglion neurons; ciliary ganglion; binding protein; channels; activation; pathways
AB NEUROTRANSMITTER release is frequently regulated by peptides that modulate neuronal calcium channels. Whole-cell recordings show that the ion permeability(1) and voltage dependence(2) of these channels are controlled by a membrane-associated pathway involving GTP-binding proteins. Here we use perforated-patch recordings to show that, in addition to this pathway, the peptide somatostatin inhibits the calcium current in chick ciliary ganglion neurons by a second soluble pathway involving a cyclic GMP-dependent protein kinase (cGMP-PK). This somatostatin inhibition of Ca2+ current did not desensitize and was not characterized by the slowing of Ca2+-current activation (kinetic slowing) observed in whole-cell recordings. When cGMP-PK was inhibited, somatostatin inhibition of Ca2+ current resembled that observed with whole-cell recordings. cGMP agonists mimic the effect of somatostatin only in perforated patch recordings. An endogenous cGMP-PK therefore forms part of the mechanism by which somatostatin induces a sustained inhibition of neuronal calcium channels.
C1 UNIV CONNECTICUT,DEPT PHYSIOL & NEUROBIOL,STORRS,CT 06269.
C3 University of Connecticut
NR 25
TC 127
Z9 135
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 336
EP 339
DI 10.1038/369336a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900055
PM 7910377
DA 2026-03-10
ER

PT J
AU NAGY, LM
   CARROLL, S
AF NAGY, LM
   CARROLL, S
TI CONSERVATION OF WINGLESS PATTERNING FUNCTIONS IN THE SHORT-GERM EMBRYOS OF TRIBOLIUM-CASTANEUM
SO NATURE
LA English
DT Article
ID segment-polarity gene; whole drosophila embryos; localization; expression
AB DURING embryogenesis, all insects reach a conserved, or phylotypic, stage at which all future segments are present1,2. Different insects, however, arrive at this stage by overtly different pathways. In the long-germ insect Drosophila melanogaster, segmentation of the entire embryo occurs nearly simultaneosly and results from the action of a cascade of transcriptional regulatory factors that operate in the acellular environment of the syncytial blastoderm3,4. In short-germ insects, segmentation occurs in an anterior-to-posterior sequence, within a cellular environment1, and might then be dependent on intercellular signalling5,6. To compare the molecular mechanisms of segmentation, we have isolated a homologue of the Drosophila wingless gene, a mediator of cell-cell communications7-9, from the short-germ beetle Tribolium castaneum. The principal features of wingless expression patterns in Drosophila are conserved in Tribolium, including its early deployment in rostral and caudal domains in the blastoderm, its segmental iteration in cells immediately anterior to cells expressing the engrailed gene, and its later restriction to a ventral sector of the developing appendages.
RP NAGY, LM (corresponding author), UNIV WISCONSIN, HOWARD HUGHES MED INST, MOLEC BIOL LAB, MADISON, WI 53706 USA.
NR 29
TC 133
Z9 148
U1 0
U2 6
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 460
EP 463
DI 10.1038/367460a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900054
PM 8107804
DA 2026-03-10
ER

PT J
AU FOING, BH
   EHRENFREUND, P
AF FOING, BH
   EHRENFREUND, P
TI DETECTION OF 2 INTERSTELLAR ABSORPTION-BANDS COINCIDENT WITH SPECTRAL FEATURES OF C-60(+)
SO NATURE
LA English
DT Article
ID polycyclic aromatic-hydrocarbons; spectroscopy; fullerenes; cations; c60; anions; carbon; c10h8+; argon
AB MORE than a hundred well-defined absorption bands, arising from diffuse gas in the interstellar medium, have been observed in the visible and near-infrared spectra of stars(1-4). The identity of the species responsible for these bands has remained unclear, although many possibilities have been suggested(5,6). Carbon-based molecules ubiquitous in the interstellar medium have been widely favoured as potential carriers of some of the diffuse interstellar bands(7-10,29); in particular, C-60(+) has been thought to be a promising candidate(9,29). Here we present the results of a search for C-60(+) in the near-infrared spectra of seven stars, based on recent laboratory measurements of the absorption spectrum of this species(11-13). We find two diffuse bands that are coincident (within 0.1%) with laboratory measurements on C-60(+) in a Ne matrix(11). From this observation and the total absorption, we estimate that 0.3-0.9% of interstellar carbon is in the form of C-60(+). The molecule is very stable, which should allow it to survive in the interstellar medium for a long time(14), but the inhibition of C-60 formation by hydrogen probably limits its abundance.
C1 LEIDEN OBSERV,2300 RA LEIDEN,NETHERLANDS.
C3 Leiden University; Leiden University - Excl LUMC
RP FOING, BH (corresponding author), EUROPEAN SPACE AGCY,ESTEC-SO,DEPT SPACE SCI,DIV SOLAR SYST,2200 AG NOORDWIJK,NETHERLANDS.
NR 29
TC 320
Z9 333
U1 0
U2 35
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 296
EP 298
DI 10.1038/369296a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900041
DA 2026-03-10
ER

PT J
AU MOORE, B
AF MOORE, B
TI EVIDENCE AGAINST DISSIPATIONLESS DARK-MATTER FROM OBSERVATIONS OF GALAXY HALOES
SO NATURE
LA English
DT Article
ID large-scale structure; spiral galaxy; galactic haloes; rotation curves; h-i; universe; mass; clusters; ngc-3109; neutrino
AB THERE are two different types of missing (dark) matter: the unseen matter needed to explain the high rotation velocities of atomic hydrogen in the outer parts of spiral galaxies(1,2), and the much larger amount of (non-baryonic) matter needed to prevent the universe from expanding forever(1) (producing either a 'flat' or a 'closed' Universe)(3). Several models have been proposed to provide the dark matter required within galaxy haloes for a flat universe, of which cold dark matter (CDM) has proved the most successful at reproducing the observed large-scale structure of the Universe(4-6). CDM belongs to a class of non-relativistic particles that interact primarily through gravity, and are named dissipationless because they cannot dissipate energy (baryonic particles can lose energy by emitting electromagnetic radiation). Here I show that the modelled small-scale properties of CDM(7-9) are fundamentally incompatible with recent observations(10-13) of dwarf galaxies, which are thought to be completely dominated by dark matter on scales larger than a kiloparsec. Thus, the hypothesis that dark matter is predominantly cold seems hard to sustain.
C1 UNIV CALIF BERKELEY, DEPT ASTRON, BERKELEY, CA 94720 USA.
C3 University of California System; University of California Berkeley
NR 34
TC 999
Z9 1105
U1 0
U2 6
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 629
EP 631
DI 10.1038/370629a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000042
DA 2026-03-10
ER

PT J
AU [Anonymous]
AF [Anonymous]
TI ASTRONOMY - EYES FIRMLY ON THE STARS
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 800
EP 800
DI 
PG 1
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700034
DA 2026-03-10
ER

PT J
AU COLLINGHAM, DP
AF COLLINGHAM, DP
TI YOUR FUTURE IN YOUR HANDS
SO NATURE
LA English
DT Article
RP COLLINGHAM, DP (corresponding author), RUSTON POOLE INT,11-12 BUCKINGHAM GATE,LONDON SW1E 6LB,ENGLAND.
NR 2
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 777
EP 778
DI 10.1038/368777a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300067
PM 8152491
DA 2026-03-10
ER

PT J
AU CHEN, TY
   YAU, KW
AF CHEN, TY
   YAU, KW
TI DIRECT MODULATION BY CA2+-CALMODULIN OF CYCLIC NUCLEOTIDE-ACTIVATED CHANNEL OF RAT OLFACTORY RECEPTOR NEURONS
SO NATURE
LA English
DT Article
ID sensitive adenylate-cyclase; gated channels; cells; cilia; transduction; conductance; odorants; newt; currents; calcium
AB OLFACTORY receptor neurons depolarize in response to odorant stimulation of their sensory cilia1-3. One transduction mechanism involves a G-protein-mediated increase in adenylate cyclase activity4-8, raising the internal cyclic AMP concentration to open a cyclic nucleotide-activated cation channel on the plasma membrane9-14. An influx of Ca2+ through this channel, which is permeable to both monovalent and divalent cations, triggers olfactory adaptation15. Previous work has indicated that at least art of this Ca2+ mediated adaptation resides in the channel itself15-17, but the mechanism remains unclear and controversial16-18. Here we use the cloned channel from rat19 expressed in a cell line and the native channel from rat olfactory receptor cells to show that Ca2+ reduces the apparent affinity of the channel for cAMP by up to 20-fold in the presence of calmodulin, an abundant protein in olfactory cilia20. This decrease in apparent affinity appears to involve a direct interaction between Ca2+-calmodulin and the channel, and it can reduce the activation of the channel by cAMP by up to a few hundred-fold, suggesting that it may be a key component of the Ca2+-triggered olfactory adaptation.
C1 JOHNS HOPKINS UNIV,SCH MED,HOWARD HUGHES MED INST,BALTIMORE,MD 21205.
C3 Howard Hughes Medical Institute; Johns Hopkins University
RP CHEN, TY (corresponding author), JOHNS HOPKINS UNIV,SCH MED,DEPT NEUROSCI,BALTIMORE,MD 21205, USA.
NR 31
TC 278
Z9 297
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 545
EP 548
DI 10.1038/368545a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500054
PM 7511217
DA 2026-03-10
ER

PT J
AU CANE, MA
   ESHEL, G
   BUCKLAND, RW
AF CANE, MA
   ESHEL, G
   BUCKLAND, RW
TI FORECASTING ZIMBABWEAN MAIZE YIELD USING EASTERN EQUATORIAL PACIFIC SEA-SURFACE TEMPERATURE
SO NATURE
LA English
DT Article
ID nino southern oscillation; el-nino
AB SOUTHERN Africa is subject to recurrent droughts which cause severe food shortages. There is considerable evidence(1) that El Nino(2) warm events in the Pacific Ocean are linked to below-average rainfall in southern Africa, and the 1991-92 El Nino event was accompanied by the worst drought in southern Africa this century, affecting nearly 100 million people. But although models can predict El Nino events a year in advance(3-6), the drought was not anticipated, increasing relief costs. Here we present data showing a strong correlation between an El Nino index and both rainfall and maize yield in Zimbabwe. Surprisingly, the correlation with maize yield is stronger than that with rainfall, with more than 60% of the variance in yield accounted for by sea surface temperatures in the eastern equatorial Pacific Ocean-half-way around the world. We also show that model predictions of the El Nino index provide accurate forecasts of maize yield in Zimbabwe, with lead times of up to a year. As maize is the most important food crop for the ten-nation Southern African Development Community region(7), we suggest that this approach could provide an effective early-warning system for southern African drought-induced famines.
C1 SADC,FOOD SECUR TECH & ADM UNIT,HARARE,ZIMBABWE.
RP CANE, MA (corresponding author), COLUMBIA UNIV,LAMONT DOHERTY EARTH OBSERV,NEW YORK,NY 10964, USA.
NR 12
TC 249
Z9 273
U1 1
U2 44
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 204
EP 205
DI 10.1038/370204a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100047
DA 2026-03-10
ER

PT J
AU BRAIG, HR
   GUZMAN, H
   TESH, RB
   ONEILL, SL
AF BRAIG, HR
   GUZMAN, H
   TESH, RB
   ONEILL, SL
TI REPLACEMENT OF THE NATURAL WOLBACHIA SYMBIONT OF DROSOPHILA-SIMULANS WITH A MOSQUITO COUNTERPART
SO NATURE
LA English
DT Article
ID cytoplasmic incompatibility; reproductive isolation; populations
AB INHERITED rickettsial symbionts of the genus Wolbachia occur commonly in arthropods and have been implicated in the expression of parthenogenesis1,2, feminization2,3 and cytoplasmic incompatibility phenomena in their respective hosts4-7. Here we use purified Wolbachia from the Asian tiger mosquito, Aedes albopictus, to replace the natural infection of Drosophila simulans by means of embryonic microinjection techniques. The transferred Wolbachia infection behaves like a natural Drosophila infection with regard to its inheritance, cytoskeleton interactions and ability to induce incompatibility when crossed with uninfected flies. The trans-infected flies are bidirectionally incompatible with all other naturally infected strains of Drosophila simulans, however, and as such represent a unique crossing type. The successful transfer of this symbiont between distantly related hosts suggests that it may be possible to introduce this agent experimentally into arthropod species of medical and agricultural importance in order to manipulate natural populations genetically.
RP BRAIG, HR (corresponding author), YALE UNIV,SCH MED,DEPT EPIDEMIOL & PUBL HLTH,POB 3333,NEW HAVEN,CT 06510, USA.
NR 24
TC 131
Z9 155
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 453
EP 455
DI 10.1038/367453a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900052
PM 7906391
DA 2026-03-10
ER

PT J
AU SILLITO, AM
   JONES, HE
   GERSTEIN, GL
   WEST, DC
AF SILLITO, AM
   JONES, HE
   GERSTEIN, GL
   WEST, DC
TI FEATURE-LINKED SYNCHRONIZATION OF THALAMIC RELAY CELL FIRING INDUCED BY FEEDBACK FROM THE VISUAL-CORTEX
SO NATURE
LA English
DT Article
ID lateral geniculate-nucleus; dependent neuronal oscillations; cross-correlation analysis; principal cells; cat; interneurons; morphology; excitation; dynamics; pathway
AB THE function of the massive feedback projection from visual cortex to its thalamic relay nucleus(1,2) has so far eluded any clear overview. This feedback exerts a range of effects(3-6), including an increase in the inhibition elicited by moving contours(7,8), but the functional logic of the direct connections to the thalamic cells that relay the retinal input to the cortex(9-11) remains largely unknown. In contrast to its thalamic nucleus, the visual cortex is characterized by cells that are strongly sensitive to the orientation of moving contours. Here we report that when driven by moving oriented visual stimuli the cortical feedback induces correlated firing in relay cells. This cortically induced correlation of relay cell activity produces coherent firing in those groups of relay cells with receptive field alignments appropriate to signalling the particular orientation of the moving contour to the cortex. Synchronization of relay cell firing means that they will elicit temporally overlapping excitatory postsynaptic potentials in their cortical target cells, thus increasing the chance that the cortical cells will fire. Effectively this increases the gain of the input for feature-linked events detected by the cortex. We propose that this feedback loop serves to lock or focus the appropriate circuitry onto the stimulus feature.
C1 UNIV PENN,SCH MED,DEPT NEUROSCI,PHILADELPHIA,PA 19104.
C3 University of Pennsylvania
RP SILLITO, AM (corresponding author), INST OPHTHALMOL,DEPT VISUAL SCI,BATH ST,LONDON EC1V 9EL,ENGLAND.
NR 21
TC 459
Z9 492
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 479
EP 482
DI 10.1038/369479a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600055
PM 8202137
DA 2026-03-10
ER

PT J
AU COPELAND, A
   LENNON, G
AF COPELAND, A
   LENNON, G
TI RAPID ARRAYED FILTER PRODUCTION USING THE ORCA ROBOT
SO NATURE
LA English
DT Article
RP COPELAND, A (corresponding author), LAWRENCE LIVERMORE NATL LAB,CTR HUMAN GENOME,BIOL & BIOTECHNOL RES PROGRAM,L-452,LIVERMORE,CA 94550, USA.
NR 8
TC 15
Z9 16
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 421
EP 422
DI 10.1038/369421a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400063
PM 8196771
DA 2026-03-10
ER

PT J
AU TSAI, LH
   DELALLE, I
   CAVINESS, VS
   CHAE, T
   HARLOW, E
AF TSAI, LH
   DELALLE, I
   CAVINESS, VS
   CHAE, T
   HARLOW, E
TI P35 IS A NEURAL-SPECIFIC REGULATORY SUBUNIT OF CYCLIN-DEPENDENT KINASE-5
SO NATURE
LA English
DT Article
ID protein-kinase; cell-cycle; brain
AB CYCLIN-dependent kinase 5 (Cdk5) was originally isolated through its structural homology to human Cdc2(1), a key regulator of cell-cycle progression(2-6). In tissue samples from adult mice, Cdk5 protein is found at the highest level in brain, at an intermediate level in testis, and at low or undetectable levels in all other tissues, but brain is the only tissue that shows Cdk5 histone H1 kinase activity(7). No equivalent kinase activity has been found in tissue culture cell lines despite high levels of Cdk5 This raised the possibility that a Cdk5 regulatory subunit was responsible for the activation of Cdk5 in brain. Here we describe the cloning and characterization of a regulatory subunit for Cdk5 known as p35. p35 displays a neuronal cell-specific pattern of expression, it associates physically with Cdk5 in vivo and activates the Cdk5 kinase. p35 differs from the mammalian cyclins and thus represents a new type of regulatory subunit for cyclin-dependent kinase activity.
C1 HARVARD UNIV,MASSACHUSETTS GEN HOSP,SCH MED,DEPT NEUROL,BOSTON,MA 02114.
   MASSACHUSETTS GEN HOSP,CTR CANC,BOSTON,MA 02129.
C3 Harvard University; Harvard Medical School; Harvard University Medical Affiliates; Massachusetts General Hospital; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital
NR 18
TC 850
Z9 946
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 419
EP 423
DI 10.1038/371419a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500043
PM 8090221
DA 2026-03-10
ER

PT J
AU GUZDER, SN
   SUNG, P
   BAILLY, V
   PRAKASH, L
   PRAKASH, S
AF GUZDER, SN
   SUNG, P
   BAILLY, V
   PRAKASH, L
   PRAKASH, S
TI RAD25 IS A DNA HELICASE REQUIRED FOR RNA REPAIR AND RNA-POLYMERASE-II TRANSCRIPTION
SO NATURE
LA English
DT Article
ID saccharomyces-cerevisiae; gene; endonuclease; initiation; encodes; rad10; protein; atpase; strand; ctd
AB THE RAD25 gene of Saccharomyces cerevisiae functions in nucleotide excision repair of ultraviolet-damaged DNA and is also required for cell viability(1). The RAD25 protein shows remarkable homology to the protein encoded by the human nucleotide-excision-repair gene XPB (ERCC3), mutations in which cause the cancer-prone disease xeroderma pigmentosum and also Cockayne's syndrome(1). Here we purify RAD25 protein from S. cerevisiae and show that it contains single-stranded DNA-dependent ATPase and DNA helicase activities. Extract from the conditional lethal mutant rad25-ts(24) exhibits a thermolabile transcriptional defect which can be corrected by the addition of RAD25 protein, indicating a direct and essential role of RAD25 in RNA polymerase II transcription. The protein encoded by the rad25(799am) allele is defective in DNA repair but is proficient in RNA polymerase II transcription, indicating that RAD25 DNA-repair activity is separable from its transcription function. The rad25 Arg-392 encoded product, which contains a mutation in the ATP-binding motif, is defective in RNA polymerase II transcription, suggesting that the RAD25-encoded DNA helicase functions in DNA duplex opening during transcription initiation.
C1 UNIV TEXAS,MED BRANCH,SEALY CTR MOLEC SCI,GALVESTON,TX 77555.
C3 University of Texas System; University of Texas Medical Branch Galveston
NR 26
TC 173
Z9 191
U1 0
U2 7
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 578
EP 581
DI 10.1038/369578a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400055
PM 8202161
DA 2026-03-10
ER

PT J
AU DAVIS, G
   DRIVER, J
AF DAVIS, G
   DRIVER, J
TI PARALLEL DETECTION OF KANIZSA SUBJECTIVE FIGURES IN THE HUMAN VISUAL-SYSTEM
SO NATURE
LA English
DT Article
ID illusory contours; apparent depth; search
AB SUBJECTIVE figures, seen in the absence of luminance gradients (Fig. 1), provide a phenomenal illusion that can be related to the properties of single cells in the visual cortex(1), offering a rare bridge between brain function and visual awareness. It remains controversial whether subjective figures arise from intelligent cognitive mechanisms(2-4), or from lower-level processes in early vision(5,6). The cognitive account implies that the perception of subjective figures may require serial attentive processing, whereas on the low-level account they should arise in parallel at earlier visual stages. Physiological evidence apparently fits a low-level account(7,8) and indicates that some types of subjective contour may be detected earlier than the conventional Kanizsa(9) type. Here we report that even Kanizsa subjective figures can be detected without focal attention at parallel stages of the human visual system.
RP DAVIS, G (corresponding author), UNIV CAMBRIDGE,DEPT EXPTL PSYCHOL,DOWNING ST,CAMBRIDGE CB2 3EA,ENGLAND.
NR 23
TC 134
Z9 141
U1 0
U2 25
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 791
EP 793
DI 10.1038/371791a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800057
PM 7935838
DA 2026-03-10
ER

PT J
AU CYSTER, JG
   HARTLEY, SB
   GOODNOW, CC
AF CYSTER, JG
   HARTLEY, SB
   GOODNOW, CC
TI COMPETITION FOR FOLLICULAR NICHES EXCLUDES SELF-REACTIVE CELLS FROM THE RECIRCULATING B-CELL REPERTOIRE
SO NATURE
LA English
DT Article
ID lymphocytes-b; transgenic mice; bone-marrow; clonal deletion; genes; expression; tolerance; lysozyme; antigen; mouse
AB Two different approaches to follow clones of B lymphocytes in a diverse preimmune repertoire reveal a new process for eliminating self-reactive cells in the periphery which depends on competition between cells with different specificities. A key feature of this censoring mechanism is the selective exclusion of self-antigen-binding B cells from the normal migration route into lymphoid follicles, resulting in their premature death. This is a striking example of homeostasis by cellular competition for limiting niches and may explain the paradoxical association between immunodeficiency and autoimmunity.
C1 STANFORD UNIV, BECKMAN CTR, SCH MED, HOWARD HUGHES MED INST, STANFORD, CA 94305 USA.
C3 Howard Hughes Medical Institute; Stanford University
RP CYSTER, JG (corresponding author), STANFORD UNIV, BECKMAN CTR, SCH MED, DEPT MICROBIOL & IMMUNOL, STANFORD, CA 94305 USA.
NR 47
TC 485
Z9 551
U1 0
U2 8
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 389
EP 395
DI 10.1038/371389a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500033
PM 7522305
DA 2026-03-10
ER

PT J
AU JONSSON, J
   CARLSSON, L
   EDLUND, T
   EDLUND, H
AF JONSSON, J
   CARLSSON, L
   EDLUND, T
   EDLUND, H
TI INSULIN-PROMOTER-FACTOR-1 IS REQUIRED FOR PANCREAS DEVELOPMENT IN MICE
SO NATURE
LA English
DT Article
ID mammalian pancreas; gene; expression; cells
AB THE mammalian pancreas is a mixed exocrine and endocrine gland that, in most species, arises from ventral and dorsal buds which subsequently merge to form the pancreas. In both mouse and rat the first histological sign of morphogenesis of the dorsal pancreas is a dorsal evagination of the duodenum ai the level of the liver at around the 22-25-somite stage, and shortly thereafter a ventral evagination appears as a derivative of the liver diverticulum(1-3). Low levels of insulin gene transcripts are already present and restricted to the dorsal foregut endoderm at 20 somites, suggesting that pancreas- or insulin gene-specific transcriptional factors are present in this region before the onset of morphogenesis(4). Insulin-promoter-factor 1 (IPF1) is a homeodomain protein which, in the adult mouse pancreas, is selectively expressed in the beta-cells and binds to and transactivates the insulin promoter(5). In mouse embryos, IPF1 expression is restricted to the developing pancreatic anlagen and is initiated when the foregut endoderm is committed to a pancreatic fate(5). We now show that mice homozygous for a targeted mutation in the Ipf1 gene selectively lack a pancreas. The mutant pups survive fetal development but die within a few days after birth. The gastrointestinal part and all other internal organs were normal in appearance. No pancreatic tissue and no ectopic expression of insulin or pancreatic amylase could be detected in mutant embryos and neonates. These findings show that IPF1 is needed for the formation of the pancreas and suggest that it acts to determine the fate of common pancreatic precursor cells and/or to regulate their propagation.
C1 UMEA UNIV,DEPT MICROBIOL,S-90187 UMEA,SWEDEN.
C3 Umea University
NR 14
TC 1527
Z9 1785
U1 1
U2 49
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 606
EP 609
DI 10.1038/371606a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900052
PM 7935793
DA 2026-03-10
ER

PT J
AU DEMUIZON, C
AF DEMUIZON, C
TI A NEW CARNIVOROUS MARSUPIAL FROM THE PALEOCENE OF BOLIVIA AND THE PROBLEM OF MARSUPIAL MONOPHYLY
SO NATURE
LA English
DT Article
ID america
AB THE distinctive soft anatomy and reproductive biology of marsupials sets them apart as a unique group within mammals. These features are, of course, absent in fossils, so it is difficult to determine marsupial origins and evolution: many of the proposed dental and skeletal characters are controversial(1) or primitive(1,2). A contribution of the alisphenoid bone to the tympanic bulla of the skull has long been considered a reliable diagnostic feature of the group(1-5). But this feature is lacking both in the borhyaenoid marsupial Mayulestes ferox, which I describe here, and the didelphoid Pucadelphys andinus(6,7), both from the early Palaeocene of Bolivia(7-9). Comparison with younger taxa suggests that this feature appeared several times independently within the group, and is thus an inappropriate defining character. What, then, is a marsupial?
RP DEMUIZON, C (corresponding author), INST FRANCAIS ETUD ANDINES,CNRS,URA 12,CASILLA 18-1217,LIMA 18,PERU.
NR 31
TC 58
Z9 61
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 21
PY 1994
VL 370
IS 6486
BP 208
EP 211
DI 10.1038/370208a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NX971
UT WOS:A1994NX97100049
DA 2026-03-10
ER

PT J
AU BEKKI, S
   LAW, KS
   PYLE, JA
AF BEKKI, S
   LAW, KS
   PYLE, JA
TI EFFECT OF OZONE DEPLETION ON ATMOSPHERIC CH4 AND CO CONCENTRATIONS
SO NATURE
LA English
DT Article
ID trace gas budgets; tropospheric ozone; methane; radicals; climate; trends
AB GLOBAL surface-based measurements of atmospheric methane and carbon monoxide concentrations revealed a marked and unexpected decrease in their growth-rates in 1991 and 1992, particularly in the Northern Hemisphere(1,2). Changes in emissions are unlikely to be the sole reason for the sudden reduction in the concentrations of these source gases(2,3). The unprecedentedly large depletion of Stratospheric ozone observed in 1991 and 1992 (ref. 4) may have contributed to the sharp decrease in the growth rates of both CH4 and CO by exposing the troposphere to more ultraviolet radiation. This would have resulted in increased concentrations of the hydroxyl radical, OH., which is the major atmospheric sink for both CH4 and CO. Here we present two-dimensional model simulations which allow us to assess the significance of the link between stratospheric ozone depletion and the observed trends of CH4 and CO. We find that the low values in stratospheric ozone concentration can account for almost half of the 1992 decrease in the CH4 and CO growth rates.
RP BEKKI, S (corresponding author), UNIV CAMBRIDGE,CTR ATMOSPHER SCI,DEPT CHEM,LENSFIELD RD,CAMBRIDGE CB2 1EW,CAMBS,ENGLAND.
NR 22
TC 114
Z9 125
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 595
EP 597
DI 10.1038/371595a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900048
DA 2026-03-10
ER

PT J
AU KYRIAKIS, JM
   BANERJEE, P
   NIKOLAKAKI, E
   DAI, TA
   RUBIE, EA
   AHMAD, MF
   AVRUCH, J
   WOODGETT, JR
AF KYRIAKIS, JM
   BANERJEE, P
   NIKOLAKAKI, E
   DAI, TA
   RUBIE, EA
   AHMAD, MF
   AVRUCH, J
   WOODGETT, JR
TI THE STRESS-ACTIVATED PROTEIN-KINASE SUBFAMILY OF C-JUN KINASES
SO NATURE
LA English
DT Article
ID necrosis-factor-alpha; tumor-necrosis; map kinase; phosphorylation; insulin; tyrosine; requires; family; domain
AB THE mitogen-activated protein (MAP) kinases Erk-1 and Erk-2 are proline-directed kinases that are themselves activated through concomitant phosphorylation of tyrosine and threonine residues(1-4). The kinase p54 (M(r) 54,000), which was first isolated from cycloheximide-treated rats, is proline-directed like Erks-1/2, and requires both Tyr and Ser/Thr phosphorylation(3,5,6) for activity. p54 is, however, distinct from Erks-1/2 in its substrate specificity, being unable to phosphorylate pp90(rsk) but more active in phosphorylating the c-Jun transactivation domain(5,7,8). Molecular cloning of p54 reveals a unique subfamily of extracellularly regulated kinases. Although they are 40-45% identical in sequence to Erks-1/2, unlike Erks-1/2 the p54s are only poorly activated in most cells by mitogens or phorbol esters. However, p54s are the principal c-Jun N-terminal kinases activated by cellular stress and tumour necrosis factor (TNF)-alpha, hence they are designated stress-activated protein kinases, or SAPKs. SAPKs are also activated by sphingomyelinase, which elicits a subset of cellular responses to TNF-alpha (ref. 9). SAPKs therefore define a new TNF-alpha and stress-activated signalling pathway, possibly initiated by sphingomyelin-based second messengers, which regulates the activity of c-Jun.
C1 PRINCESS MARGARET HOSP, ONTARIO CANC INST, TORONTO M4X 1K9, ON, CANADA.
C3 University of Toronto; University Health Network Toronto; Princess Margaret Cancer Centre
RP KYRIAKIS, JM (corresponding author), MASSACHUSETTS GEN HOSP E, MED SERV, DIABET RES LAB, 149 13TH ST, BOSTON, MA 02129 USA.
NR 31
TC 2508
Z9 2706
U1 0
U2 73
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 156
EP 160
DI 10.1038/369156a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100052
PM 8177321
DA 2026-03-10
ER

PT J
AU MCGUIRE, W
   HILL, AVS
   ALLSOPP, CEM
   GREENWOOD, BM
   KWIATKOWSKI, D
AF MCGUIRE, W
   HILL, AVS
   ALLSOPP, CEM
   GREENWOOD, BM
   KWIATKOWSKI, D
TI VARIATION IN THE TNF-ALPHA PROMOTER REGION ASSOCIATED WITH SUSCEPTIBILITY TO CEREBRAL MALARIA
SO NATURE
LA English
DT Article
ID tumor-necrosis-factor; major histocompatibility complex; b-cell lines; falciparum-malaria; plasmodium-falciparum; gene-regulation; t-cell; polymorphism; protection; cachectin
AB TUMOUR-necrosis factor-alpha (TNF-alpha) is believed to have an important role in the pathogenesis of severe infectious disease(1) and fatal cerebral malaria is associated with high circulating levels of this cytokine(2,3). In a large case-control study in Cambian children we find that homozygotes for the TNF2 allele, a variant of the TNF-alpha gene promoter region(4), have a relative risk of 7 for death or severe neurological sequelae due to cerebral malaria. Although the TNF2 allele is in linkage disequilibrium with several neighbouring HLA alleles, we show that this disease association is independent of HLA class I and class II variation. These data suggest that regulatory polymorphisms of cytokine genes can affect the outcome of severe infection. The maintenance of the TNF2 allele at a gene frequency of 0.16 in The Gambia implies that the increased risk of cerebral malaria in homozygotes is counterbalanced by some biological advantage.
C1 JOHN RADCLIFFE HOSP,INST MOLEC MED,MOLEC IMMUNOL GRP,OXFORD OX3 9DU,ENGLAND.
   MRC LABS,FAJARA,SENEGAL.
C3 University of Oxford
RP MCGUIRE, W (corresponding author), JOHN RADCLIFFE HOSP,DEPT PAEDIAT,OXFORD OX3 9DU,ENGLAND.
FU Wellcome Trust Funding Source: Medline
NR 30
TC 1058
Z9 1120
U1 0
U2 26
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 508
EP 511
DI 10.1038/371508a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900053
PM 7935762
DA 2026-03-10
ER

PT J
AU HURLEY, K
   DINGUS, BL
   MUKHERJEE, R
   SREEKUMAR, P
   KOUVELIOTOU, C
   MEEGAN, C
   FISHMAN, GJ
   BAND, D
   FORD, L
   BERTSCH, D
   CLINE, T
   FICHTEL, C
   HARTMAN, R
   HUNTER, S
   THOMPSON, DJ
   KANBACH, G
   MAYERHASSELWANDER, H
   VONMONTIGNY, C
   SOMMER, M
   LIN, Y
   NOLAN, P
   MICHELSON, P
   KNIFFEN, D
   MATTOX, J
   SCHNEID, E
   BOER, M
   NIEL, M
AF HURLEY, K
   DINGUS, BL
   MUKHERJEE, R
   SREEKUMAR, P
   KOUVELIOTOU, C
   MEEGAN, C
   FISHMAN, GJ
   BAND, D
   FORD, L
   BERTSCH, D
   CLINE, T
   FICHTEL, C
   HARTMAN, R
   HUNTER, S
   THOMPSON, DJ
   KANBACH, G
   MAYERHASSELWANDER, H
   VONMONTIGNY, C
   SOMMER, M
   LIN, Y
   NOLAN, P
   MICHELSON, P
   KNIFFEN, D
   MATTOX, J
   SCHNEID, E
   BOER, M
   NIEL, M
TI DETECTION OF A GAMMA-RAY BURST OF VERY LONG-DURATION AND VERY-HIGH-ENERGY
SO NATURE
LA English
DT Article
ID egret
AB ALTHOUGH gamma-ray bursts (GRBs) have been known for more than 20 years, their origin remains mysterious(1). Suggestions have ranged from nearby colliding comets(2) to merging neutron stars at cosmological distances(3). The lack of any counterpart at wavelengths other than X-rays and gamma-rays has posed a major problem in identifying the source of GRBs(4). Although in principle the distribution of energies among the burst photons, as well as their light curves, may be used to constrain the potential sources, this has proved difficult in practice(5). Here we present the observation of a particularly energetic burst with a duration of 90 minutes, which includes the detection of an 18-GeV photon. For comparison, typical GRBs emit photons in the energy range between a few keV and a few tens of MeV, and last a few tens of seconds(6,7). The extended nature of this burst holds out the hope that there will be opportunities for telescopes operating at other wavelengths to detect a GRB source white it is still active, thus providing further constraints on the source's identity and properties.
C1 NASA,GODDARD SPACE FLIGHT CTR,UNIV SPACE RES ASSOC,GREENBELT,MD 20771.
   NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,HUNTSVILLE,AL 35812.
   UNIV CALIF SAN DIEGO,CTR ASTROPHYS & SPACE SCI,SAN DIEGO,CA 92093.
   MAX PLANCK INST EXTRATERR PHYS,W-8046 GARCHING,GERMANY.
   STANFORD UNIV,HANSEN EXPTL PHYS LAB,STANFORD,CA 94305.
   HAMPDEN SYDNEY COLL,HAMPDEN SYDNEY,VA 23943.
   USRA,COMPTON OBSERV SCI SUPPORT CTR,WASHINGTON,DC.
   NORTHRUP GRUMMAN CORP,BETHPAGE,NY 11714.
   CTR ETUD SPATIALE RAYONNEMENTS,F-31029 TOULOUSE,FRANCE.
C3 National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center; Universities Space Research Association (USRA); National Aeronautics & Space Administration (NASA); NASA Marshall Space Flight Center; University of California System; University of California San Diego; Max Planck Society; Stanford University; Universite de Toulouse; Universite Toulouse III - Paul Sabatier
RP HURLEY, K (corresponding author), UNIV CALIF BERKELEY,SPACE SCI LAB,BERKELEY,CA 94720, USA.
NR 21
TC 512
Z9 537
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 652
EP 654
DI 10.1038/372652a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700078
DA 2026-03-10
ER

PT J
AU MCGAUGH, SS
AF MCGAUGH, SS
TI A POSSIBLE LOCAL COUNTERPART TO THE EXCESS POPULATION OF FAINT BLUE GALAXIES
SO NATURE
LA English
DT Article
ID surface brightness galaxy; redshift survey; luminosity function; evolution; counts; disks
AB OBSERVATIONS have revealed a population of faint blue galaxies1-5 at intermediate redshifts (z almost-equal-to 0.4). These galaxies are present in significant excess relative to what is expected based on observations of local galaxies, which has led some to propose that the discrepancy must be due either to non-standard cosmologies4,6 or to the effects of very pronounced galaxy evolution4,7-10. The surveys that define the population of local galaxies are strongly biased against objects of low surface brightness11-14. Recent work15,16 has shown that nearby low-surface-brightness galaxies have properties very similar to those of the excess faint blue galaxies, and has suggested that they may be as common as normal spiral galaxies14,17. Here I show that the deep surveys that have identified the faint blue galaxies can easily detect low-surface-brightness galaxies at intermediate redshifts, even though they are not readily apparent in local surveys. Thus, the faint blue galaxies may indeed correspond to low-surface-brightness galaxies.
RP MCGAUGH, SS (corresponding author), UNIV CAMBRIDGE, INST ASTRON, MADINGLEY RD, CAMBRIDGE CB3 0HA, ENGLAND.
NR 37
TC 86
Z9 86
U1 0
U2 0
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 538
EP 541
DI 10.1038/367538a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300051
DA 2026-03-10
ER

PT J
AU BLUNDY, J
   WOOD, B
AF BLUNDY, J
   WOOD, B
TI PREDICTION OF CRYSTAL-MELT PARTITION-COEFFICIENTS FROM ELASTIC-MODULI
SO NATURE
LA English
DT Article
ID volume relationship; element; clinopyroxene; patterns
AB MANY geochemical processes, such as crystallization of silicate magmas or planetary differentiation, require a knowledge of the way in which elements become partitioned between coexisting crystal and liquid phases(1,2). But quantitative prediction of crystal/melt partition coefficients from thermodynamic principles has not previously been possible. By studying the partitioning of 15 elements between silicate minerals and their coexisting melts, we show here that the partitioning behaviour of any series of isovalent cations can be rationalized in terms of a simple model in which the size and elasticity of the crystal lattice sties play a critical role. We find that elasticity varies linearly with the formal charge of the cation. This model allows us to predict element partitioning behaviour solely from the physical characteristics of the cation sites in the crystal.
RP BLUNDY, J (corresponding author), UNIV BRISTOL,DEPT GEOL,CETSEI,WILLS MEM BLDG,BRISTOL BS8 1RJ,AVON,ENGLAND.
NR 34
TC 900
Z9 981
U1 6
U2 175
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 1
PY 1994
VL 372
IS 6505
BP 452
EP 454
DI 10.1038/372452a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PV012
UT WOS:A1994PV01200053
DA 2026-03-10
ER

PT J
AU FOSTER, JW
   DOMINGUEZSTEGLICH, MA
   GUIOLI, S
   KWOK, C
   WELLER, PA
   STEVANOVIC, M
   WEISSENBACH, J
   MANSOUR, S
   YOUNG, ID
   GOODFELLOW, PN
   BROOK, JD
   SCHAFER, AJ
AF FOSTER, JW
   DOMINGUEZSTEGLICH, MA
   GUIOLI, S
   KWOK, C
   WELLER, PA
   STEVANOVIC, M
   WEISSENBACH, J
   MANSOUR, S
   YOUNG, ID
   GOODFELLOW, PN
   BROOK, JD
   SCHAFER, AJ
TI CAMPOMELIC DYSPLASIA AND AUTOSOMAL SEX REVERSAL CAUSED BY MUTATIONS IN AN SRY-RELATED GENE
SO NATURE
LA English
DT Article
ID camptomelic dwarfism; determining region; y-chromosome; deletion; protein; inheritance; sequences; encodes; sox-4; mouse
AB Induction of testis development in mammals requires the presence of the Y-chromosome gene SRY. This gene must exert its effect by interacting with other genes in the sex-determination pathway. Cloning of a translocation chromosome breakpoint from a sex-reversed patient with campomelic dysplasia, followed by mutation analysis of an adjacent gene, indicates that SOX9, an SRY-related gene, is involved in both bone formation and control of testis development.
C1 UNIV CAMBRIDGE,DEPT GENET,CAMBRIDGE CB2 3EH,ENGLAND.
   CITY HOSP,CTR MED GENET,NOTTINGHAM,ENGLAND.
   UNIV NOTTINGHAM,QUEENS MED CTR,DEPT GENET,NOTTINGHAM NG7 2UH,ENGLAND.
   LAB GENETHON,F-91002 EVRY,FRANCE.
   INST CHILD HLTH,LONDON WC1N 1EH,ENGLAND.
C3 University of Cambridge; University of Nottingham; University of Nottingham; University of London; University College London
FU Wellcome Trust Funding Source: Medline
NR 44
TC 1312
Z9 1500
U1 2
U2 57
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 525
EP 530
DI 10.1038/372525a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200044
PM 7990924
DA 2026-03-10
ER

PT J
AU COE, RS
   LIDDICOAT, JC
AF COE, RS
   LIDDICOAT, JC
TI OVERPRINTING OF NATURAL MAGNETIC REMANENCE IN LAKE-SEDIMENTS BY A SUBSEQUENT HIGH-INTENSITY FIELD
SO NATURE
LA English
DT Article
ID geomagnetic excursion; secular variation; california; records; transition; reversals; artifact; basin
AB THERE has been considerable debate recently on how well sedimentary rocks record transitional field directions during a polarity reversal1-5. This has not been an easy question to answer because the input geomagnetic signal for a given sedimentary record is not known independently, and because the process by which remanent magnetization is acquired by sediments is difficult to duplicate in the laboratory. The geomagnetic excursion recorded by sediments outcropping around the shores of Mono Lake, California6-8, offers an unusually good opportunity to examine this question. We report here a study of the Mono Lake Excursion (MLE) at a new locality on the southeast shore where, although the records satisfy usually applied standards of palaeomagnetic quality, it is clear from comparison with records from other localities that the field directions during a time of low field intensity have not been faithfully preserved. The distinctive directions of natural remanence in the discrepant part of the record show that the southeast shore sediments were overprinted by the ensuing higher-intensity field acting on the still unconsolidated sediment, apparently by realigning some magnetic grains that had previously been locked in.
C1 COLUMBIA UNIV BARNARD COLL,NEW YORK,NY 10027.
C3 Columbia University
RP COE, RS (corresponding author), UNIV CALIF SANTA CRUZ,DEPT EARTH SCI,SANTA CRUZ,CA 95064, USA.
NR 20
TC 45
Z9 49
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 6
PY 1994
VL 367
IS 6458
BP 57
EP 59
DI 10.1038/367057a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MP865
UT WOS:A1994MP86500056
DA 2026-03-10
ER

PT J
AU PAK, HK
   BEHRINGER, PR
AF PAK, HK
   BEHRINGER, PR
TI BUBBLING IN VERTICALLY VIBRATED GRANULAR-MATERIALS
SO NATURE
LA English
DT Article
ID sand
AB GRANULAR materials show both fluid-like and solid-like behaviour. Under weak shear they deform plastically; under high shear they flow. These materials exhibit other unusual kinds of behaviour, including segregation(1), density waves(2), convection(3) and anomalous sound propagation(4). Their dynamical properties are important in many industrial applications(5-7), In particular, the shaking of granular materials is used to mix, segregate and transport them. Vertically shaken granular materials undergo a transition to a convective state(6-14). Here we describe experiments which show that such convective motion can involve bubbling-the formation and upward motion of voids. The presence of gas between the grains is essential for bubbling to occur, and the instability shows characteristics of a Hopf bifurcation such as is seen at the onset of chaos. This bubbling behaviour may be analogous to that observed in fluidized beds(15,16), and might be expected to occur when soils are fluidized during earthquakes.
C1 DUKE UNIV,CTR NONLINEAR & COMPLEX SYST,DURHAM,NC 27708.
C3 Duke University
RP PAK, HK (corresponding author), DUKE UNIV,DEPT PHYS,DURHAM,NC 27708, USA.
NR 16
TC 98
Z9 101
U1 0
U2 31
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 231
EP 233
DI 10.1038/371231a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000046
DA 2026-03-10
ER

PT J
AU MURRAY, AB
   PAOLA, C
AF MURRAY, AB
   PAOLA, C
TI A CELLULAR-MODEL OF BRAIDED RIVERS
SO NATURE
LA English
DT Article
ID gravel-bed rivers; transport; morphology; patterns
AB A BROAD Sheet of water flowing over non-cohesive sediment typ- ically breaks up into a network of interconnected channels called a braided stream (Fig. 1). The dynamics of such networks are complex; channels migrate laterally, split, rejoin and develop bars, with the flow shifting unpredictably from one part of the network to another. Many processes are known to operate in a braided river(1-3), but it is unclear which of these are essential to explain the observed dynamics. We describe here a simple, deterministic numerical model of water flow over a cohesionless bed that captures the main spatial and temporal features of real braided rivers. The patterns arise from local scour and deposition caused by a nonlinear dependence of bedload sediment flux on water discharge. Although the morphology of the resulting network depends in detail on the sediment-transport rule used in the model, our results suggest that the only factors essential for braiding are bedload sediment transport and laterally unconstrained free-surface flow.
RP MURRAY, AB (corresponding author), UNIV MINNESOTA, DEPT GEOL & GEOPHYS, MINNEAPOLIS, MN 55455 USA.
NR 30
TC 349
Z9 409
U1 1
U2 99
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 54
EP 57
DI 10.1038/371054a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100047
DA 2026-03-10
ER

PT J
AU LAWANDY, NM
   BALACHANDRAN, RM
   GOMES, ASL
   SAUVAIN, E
AF LAWANDY, NM
   BALACHANDRAN, RM
   GOMES, ASL
   SAUVAIN, E
TI LASER ACTION IN STRONGLY SCATTERING MEDIA
SO NATURE
LA English
DT Article
ID spontaneous emission
AB THE radiative properties of an atomic or molecular system may be altered significantly in the presence of coherent optical scattering1,2. In the course of investigating the radiative properties of a laser dye dispersed in a strongly scattering medium (a colloidal suspension of titanium dioxide particles), we have found that the emissions from such systems can exhibit spectral and temporal properties characteristic of a multimode laser oscillator, even though the systems contain no external cavity. The threshold excitation energy for laser action is surprisingly low. We suggest that these composite systems might find applications in laser instrumentation and photonics.
C1 BROWN UNIV,DEPT PHYS,PROVIDENCE,RI 02912.
C3 Brown University
RP LAWANDY, NM (corresponding author), BROWN UNIV,DIV ENGN,PROVIDENCE,RI 02912, USA.
NR 6
TC 1271
Z9 1349
U1 0
U2 202
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 436
EP 438
DI 10.1038/368436a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000056
DA 2026-03-10
ER

PT J
AU PELLMYR, O
   HUTH, CJ
AF PELLMYR, O
   HUTH, CJ
TI EVOLUTIONARY STABILITY OF MUTUALISM BETWEEN YUCCAS AND YUCCA MOTHS
SO NATURE
LA English
DT Article
ID fruit abortion; pollinators; selection; flower; plants; fig
AB INTERSPECIFIC mutualisms inherently possess a conflict of interests between the interacting species in that fitness increases of one species occur at the expense of the other. This holds for mutualisms as diverse as plant associations with mycorrhizal fungi or nitrogen-fixing bacteria, animals and endosymbionts, and obligate plant-pollinator associations(1-6). Prevailing models of interspecific cooperation predict that mutualistic interactions are evolutionarily stable only when both interacting species possess mechanisms to prevent excessive exploitation(3-6). In light of this, it is paradoxical that some of the classical examples of coevolved obligate mutualism seemingly do not meet this criterion. In mutualisms involving seed parasites that actively pollinate their hosts, such as yucca/ yucca moth and fig/fig wasp interactions, there is no apparent means of retaliation on behalf of the plant. Predictions from theory suggest that a cryptic mechanism, such as selective abortion of flowers with heavy egg loads, could stabilize these interactions(4,6-9). Here we present the first empirical evidence that such a mechanism in fact exists in the yucca/yucca moth interaction. A strong negative effect exists between moth egg number and probability of flower retention. Furthermore, we show a strong positive effect between the number of pollinations received and the probability of flower retention. Selective maturation of fruit with low egg loads and high pollen loads provides a mechanism to increase the quantity and possibly quality of seeds produced, and simultaneously select against moths that lay many eggs per flower or provide low-quality pollinations(4,6,8,10). Not only can these results explain the stability of this type of interaction, but selection for high-quality pollination also provides a mechanism to help explain the evolution of active pollination among yucca moths.
RP PELLMYR, O (corresponding author), VANDERBILT UNIV,DEPT BIOL,NASHVILLE,TN 37235, USA.
NR 30
TC 346
Z9 385
U1 5
U2 236
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 257
EP 260
DI 10.1038/372257a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900048
DA 2026-03-10
ER

PT J
AU OAKLANDER, AL
   EKENBERG, SJ
AF OAKLANDER, AL
   EKENBERG, SJ
TI SMALL-SCALE MAGNETIC ISOLATION OF MESSENGER-RNA AND SYNTHESIS OF CDNA IN 96-WELL PLATES
SO NATURE
LA English
DT Article
ID reverse-transcriptase-pcr
AB Multiple small biological samples can be simultaneously prepared for RT-PCR by magnetically isolating mRNA and synthesizing cDNA in 96-well plates. The resulting accuracy, high throughput and ease of use facilitate commercial and clinical applications.
C1 PROMEGA CORP,MADISON,WI.
C3 Promega Corporation
RP OAKLANDER, AL (corresponding author), JOHNS HOPKINS MED INST,DEPT NEUROL,BALTIMORE,MD 21205, USA.
NR 7
TC 8
Z9 9
U1 1
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 631
EP 632
DI 10.1038/371631a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900060
PM 7523954
DA 2026-03-10
ER

PT J
AU LIM, WA
   RICHARDS, FM
   FOX, RO
AF LIM, WA
   RICHARDS, FM
   FOX, RO
TI STRUCTURAL DETERMINANTS OF PEPTIDE-BINDING ORIENTATION AND OF SEQUENCE SPECIFICITY IN SH3 DOMAINS
SO NATURE
LA English
DT Article
ID crystal-structure; tyrosine kinases; protein; sos; association; sevenless; exchange; grb2
AB THE Src-homology-3 (SH3) domains of the Caenorhabditis elegans protein SEM-5 and its human and Drosophila homologues, Grb2 and Drk (refs 1-4), bind proline-rich sequences found in the nucleotide-exchange factor Sos as part of their proposed function linking receptor tyrosine kinase activation to Ras activation(5-7). Here we report the crystal structure at 2.0 Angstrom resolution of the carboxy-terminal SH3 domain from SEM-5 complexed to the mSos-derived amino-acid sequence PPPVPPRRR. The peptide is found to bind in an orientation ('minus') that is precisely opposite to that observed previously ('plus' orientation) in other SH3-peptide complexes(8,9). This novel ability of peptide-recognition proteins to recognize peptides in two distinct modes may play an important role in the signalling specificity of pathways involving SH3 domains. Comparison of this structure with other SH3 complexes reveals how a conserved binding face can be used to recognize peptides in different orientations, and why the Sos peptide binds in this particular orientation.
C1 YALE UNIV,HOWARD HUGHES MED INST,NEW HAVEN,CT 06520.
C3 Howard Hughes Medical Institute; Yale University
RP LIM, WA (corresponding author), YALE UNIV,DEPT MOLEC BIOPHYS & BIOCHEM,POB 6666,NEW HAVEN,CT 06520, USA.
NR 28
TC 494
Z9 550
U1 0
U2 42
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 375
EP 379
DI 10.1038/372375a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700059
PM 7802869
DA 2026-03-10
ER

PT J
AU GHADIRI, MR
   GRANJA, JR
   BUEHLER, LK
AF GHADIRI, MR
   GRANJA, JR
   BUEHLER, LK
TI ARTIFICIAL TRANSMEMBRANE ION CHANNELS FROM SELF-ASSEMBLING PEPTIDE NANOTUBES
SO NATURE
LA English
DT Article
ID synthetic proteins; membranes; transport; vesicles; design; gramicidin; liposm; bilayers; model
AB NATURALLY occurring membrane channels and pores are formed from a large family of diverse proteins, peptides and organic secondary metabolites whose vital biological functions include control of ion flow, signal transduction, molecular transport and production of cellular toxins. But despite the availability of a large amount of biochemical information about these molecules(1), the design and synthesis of artificial systems that can mimic the biological function of natural compounds remains a formidable task(2-12). Here we present a simple strategy for the design of artificial membrane ion channels based on a self-assembled cylindrical beta-sheet peptide architecture(13). Our systems-essentially stacks of peptide rings-display good channel-mediated ion-transport activity with rates exceeding 10(7) ions s(-1), rivalling the performance of many naturally occurring counterparts. Such molecular assemblies should find use in the design of novel cytotoxic agents, membrane transport vehicles and drug-delivery systems.
C1 SCRIPPS RES INST, DEPT MOLEC BIOL & CELL BIOL, LA JOLLA, CA 92307 USA.
C3 Scripps Research Institute
RP GHADIRI, MR (corresponding author), SCRIPPS RES INST, DEPT CHEM, LA JOLLA, CA 92307 USA.
NR 32
TC 871
Z9 983
U1 6
U2 297
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 26
PY 1994
VL 369
IS 6478
BP 301
EP 304
DI 10.1038/369301a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NN109
UT WOS:A1994NN10900043
PM 7514275
DA 2026-03-10
ER

PT J
AU WOODS, AW
   KOYAGUCHI, T
AF WOODS, AW
   KOYAGUCHI, T
TI TRANSITIONS BETWEEN EXPLOSIVE AND EFFUSIVE ERUPTIONS OF SILICIC MAGMAS
SO NATURE
LA English
DT Article
ID gas content; st-helens; dynamics; volcanism; geometry; growth; flow
AB WATER-RICH silicic magmas may erupt explosively, giving rise to massive columns of fragmented ash(1-5), or effusively as viscous, bubbly lavas to form lava domes(6-8). Complex cycles of explosive and effusive eruptions are often observed(8-12). Although these two eruption mechanisms have been modelled independently(1,8), the conditions under which a volcano exhibits a particular style of suption are not known and the transitions between eruption styles are poorly understood. By modelling the ascent of magma along a permeable conduit, we show here that, for small magma-chamber overpressures, the style of eruption-explosive or effusive-is dependent on the magma flow rate. We also identify a critical overpressure above which only explosive eruptions occur. Complex eruption sequences follow naturally. For example, if a shallow magmatic system is supplied with magma at an intermediate flow rate, the eruption will be slow and effusive until the chamber over-pressure becomes too large. An explosive eruption then relieves the overpressure and an effusive eruption style resumes. We suggest that monitoring of temporal variations in chamber overpressure (for example, by measuring ground deformation) can be used to assess whether a passively effusing volcano has the potential to erupt explosively.
C1 UNIV TOKYO,EARTHQUAKE RES INST,TOKYO 113,JAPAN.
C3 University of Tokyo
RP WOODS, AW (corresponding author), UNIV CAMBRIDGE,INST THEORET GEOPHYS,20 SILVER ST,CAMBRIDGE CB3 9EW,ENGLAND.
NR 21
TC 255
Z9 276
U1 1
U2 39
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 641
EP 644
DI 10.1038/370641a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000047
DA 2026-03-10
ER

PT J
AU CHAKRABARTI, SK
   ROSNER, R
   VAINSHTEIN, SI
AF CHAKRABARTI, SK
   ROSNER, R
   VAINSHTEIN, SI
TI POSSIBLE ROLE OF MASSIVE BLACK-HOLES IN THE GENERATION OF GALACTIC MAGNETIC-FIELDS
SO NATURE
LA English
DT Article
ID origin
AB THE origin of galactic magnetic fields has been a long-standing puzzle. Models based on standard dynamo theory1-4 encounter several problems, the most fundamental of which is that, in order to explain the strengths of observed large-scale magnetic field5-7, the fluctuating magnetic fields in galaxies must be unreasonably large8-12: the energy density in these small-scale fields must far exceed the local kinetic energy density. Here we propose an alternative mechanism of magnetic-field generation in galaxies. We show that a seed field can be generated by the rotation of an aspherical cloud of ionized gas around a central massive black hole. Strong shear flows in the rotating gas amplify this seed field, and a relatively slow galactic wind can transport the field to the outer regions of a galaxy in about 100 million years-a timescale short enough to meet the constraints imposed by the observation of strong fields in very young galaxies13,14.
C1 INT CTR THEORET PHYS, I-34100 TRIESTE, ITALY.
   UNIV CHICAGO, DEPT PHYS & ASTRON, CHICAGO, IL 60637 USA.
C3 Abdus Salam International Centre for Theoretical Physics (ICTP); University of Chicago
RP CHAKRABARTI, SK (corresponding author), TATA INST FUNDAMENTAL RES, BOMBAY 400005, INDIA.
NR 28
TC 30
Z9 31
U1 0
U2 1
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 434
EP 436
DI 10.1038/368434a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000055
DA 2026-03-10
ER

PT J
AU GRAVELAND, J
   VANDERWAL, R
   VANBALEN, JH
   VANNOORDWIJK, AJ
AF GRAVELAND, J
   VANDERWAL, R
   VANBALEN, JH
   VANNOORDWIJK, AJ
TI POOR REPRODUCTION IN FOREST PASSERINES FROM DECLINE OF SNAIL ABUNDANCE ON ACIDIFIED SOILS
SO NATURE
LA English
DT Article
ID shell thickness; acidity
AB ON poor, acidified soils in The Netherlands, an increasing number of great tits, Parus major, and other forest passerines, produce eggs with thin and porous shells1.  Here we show that the egg-shell defects, and the related high incidence of clutch desertion and empty nests, are caused by calcium deficiency, that snail shells are the main calcium source for the laying female, but that snails are scarce on poor soils. Similar laying irregularities in birds are reported from acidified regions elsewhere in Europe2-4. We provide evidence that snails declined by a decrease in soil calcium on poor soils. Acid deposition is the main cause for decreasing calcium levels in such soils5-7. To our knowledge, this is the first experimental evidence for calcium limitation in wild birds and it reveals a previously overlooked mechanism by which acidification affects higher trophic levels of the forest ecosystem.
C1 NETHERLANDS INST ECOL,CTR TERR ECOL,6666 ZG HETEREN,NETHERLANDS.
   UNIV GRONINGEN,ZOOL LAB,9700 AB GRONINGEN,NETHERLANDS.
C3 Royal Netherlands Academy of Arts & Sciences; Netherlands Institute of Ecology (NIOO-KNAW); University of Groningen
NR 25
TC 232
Z9 268
U1 1
U2 44
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 446
EP 448
DI 10.1038/368446a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000060
DA 2026-03-10
ER

PT J
AU ROMANEK, CS
   GRADY, MM
   WRIGHT, IP
   MITTLEFEHLDT, DW
   SOCKI, RA
   PILLINGER, CT
   GIBSON, EK
AF ROMANEK, CS
   GRADY, MM
   WRIGHT, IP
   MITTLEFEHLDT, DW
   SOCKI, RA
   PILLINGER, CT
   GIBSON, EK
TI RECORD OF FLUID-ROCK INTERACTIONS ON MARS FROM THE METEORITE ALH84001
SO NATURE
LA English
DT Article
ID isotope fractionations; stable isotopes; snc meteorites; carbon-dioxide; oxygen; calcite; evolution
AB ALLAN HILLS (ALH) 84001 is the most recently recognized(1) member of a suite of meteorites-the SNCs-that almost certainly originated on Mars(2). Several factors distinguish ALH84001 from the other SNC meteorites. Preliminary studies(3,4) suggest that it may be older than other martian meteorites. Moreover, it contains abundant, zoned domains of calcium-iron-magnesium carbonate that are indigenous to the sample(1) and thus may hold important clues regarding near-surface processes on Mars and the evolution of the martian atmosphere. We report here analyses of the carbon and oxygen stable-isotope Compositions of the carbonates that place constraints on their formation conditions. Our results imply the presence of at least two chemically distinct carbonates-one Ca,Fe-rich, the other Mg-rich-that are enriched in C-13 relative to terrestrial carbonates (delta(13)C approximate to + 41%parts per thousand), consistent with martian atmospheric CO2 as the carbon source. The oxygen isotope compositions of the carbonates indicate that they precipitated from a low-temperature fluid in the martian crust. Combined with textural and bulk geochemical considerations, the isotope data suggest that carbonate deposition took place in an open-system environment in which the ambient temperature fluctuated.
C1 BRITISH MUSEUM NAT HIST,DEPT MINERAL,LONDON SW7 5BD,ENGLAND.
   OPEN UNIV,DEPT EARTH SCI,PLANETARY SCI UNIT,MILTON KEYNES MK7 6AA,BUCKS,ENGLAND.
   LOCKHEED ENGN & SCI CO,HOUSTON,TX 77058.
C3 British Museum of Natural History; Open University - UK; Lockheed Martin
RP ROMANEK, CS (corresponding author), NASA,LYNDON B JOHNSON SPACE CTR,PLANETARY SCI BRANCH SN4,HOUSTON,TX 77058, USA.
NR 25
TC 208
Z9 214
U1 1
U2 39
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 655
EP 657
DI 10.1038/372655a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700079
PM 7990956
DA 2026-03-10
ER

PT J
AU ROMER, AK
   COLLINS, CA
   BOHRINGER, H
   CRUDDACE, RG
   EBELING, H
   MACGILLIVRAY, HT
   VOGES, W
AF ROMER, AK
   COLLINS, CA
   BOHRINGER, H
   CRUDDACE, RG
   EBELING, H
   MACGILLIVRAY, HT
   VOGES, W
TI THE LARGE-SCALE DISTRIBUTION OF X-RAY-CLUSTERS OF GALAXIES
SO NATURE
LA English
DT Article
ID cold dark matter; rich clusters; redshift survey; abell clusters; universe; catalog; apm
AB CLUSTERS of galaxies are not distributed randomly in space, but are themselves clustered, reflecting inhomogeneities in the early Universe(1). The degree of clustering-usually expressed as a correlation length, which measures the characteristic scale for clustering-can therefore be used to determine the size of the initial density fluctuations that gave rise to the clusters(1-3). Optical studies of galaxy clusters(4-7) have indicated a correlation length that conflicts with the predictions of some theories of large-scale structure formation(1-3), leading to the suggestion that these optical samples are biased in that foreground or background galaxies not physi ically associated with a cluster are counted as part of it(8-10). Here we report a measurement of the correlation length for a sample of clusters that were selected based on their X-ray emission, which is free from the bias that is inherent to optical studies. We find a correlation length of 13-15 h(-1) Mpc, where h is the Hubble constant in units of 100 km s(-1) Mpc(-1). There is no evidence for clusters being significantly elongated along the line of sight, contrary to previous suggestions(11,12).
C1 NORTHWESTERN UNIV, DEPT PHYS & ASTRON, EVANSTON, IL 60208 USA.
   LIVERPOOL JOHN MOORES UNIV, ASTROPHYS GRP, LIVERPOOL L3 3AF, MERSEYSIDE, ENGLAND.
   MAX PLANCK INST EXTRATERR PHYS, W-8046 GARCHING, GERMANY.
   USN, RES LAB, WASHINGTON, DC 20375 USA.
   UNIV CAMBRIDGE, INST ASTRON, CAMBRIDGE CB3 0HA, ENGLAND.
   ROYAL OBSERV, EDINBURGH EH9 3HJ, MIDLOTHIAN, SCOTLAND.
C3 Northwestern University; Liverpool John Moores University; Max Planck Society; United States Department of Defense; United States Navy; United States Naval Research Laboratory; NRL Chesapeake; University of Cambridge; University of Edinburgh
RP ROMER, AK (corresponding author), UNIV DURHAM, DEPT PHYS, SOUTH RD, DURHAM DH1 3LE, ENGLAND.
NR 25
TC 57
Z9 57
U1 0
U2 0
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 75
EP 77
DI 10.1038/372075a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800072
DA 2026-03-10
ER

PT J
AU BARRES, BA
   RAFF, MC
   GAESE, F
   BARTKE, I
   DECHANT, G
   BARDE, YA
AF BARRES, BA
   RAFF, MC
   GAESE, F
   BARTKE, I
   DECHANT, G
   BARDE, YA
TI A CRUCIAL ROLE FOR NEUROTROPHIN-3 IN OLIGODENDROCYTE DEVELOPMENT
SO NATURE
LA English
DT Article
ID central-nervous-system; glial progenitor-cell; growth-factor; monoclonal-antibody; neuronal death; differentiation; astrocyte; culture; invitro; antigen
AB THE neurotrophins nerve growth factor, brain-derived neurotrophic factor, neurotrophin-3 and neurotrophin4/5 promote the survival of subpopulations of vertebrate neurons in vitro, but so far only nerve growth factor has been demonstrated to be essential for normal neuronal development1-4; no neurotrophin has previously been shown to function in normal glial cell development.  We found recently that neurotrophin-3 promotes the survival of pure oligodendrocyte precursor cells in vitro, and although by itself it induces only a small percentage of these cells to synthesize DNA, in combination with platelet-derived growth factor it induces the majority of them to do so5.  Neither of these factors, however, has been shown to contribute to oligodendrocytes precursor cell proliferation in vivo or to stimulate pure populations of these cells to proliferate (as opposed to synthesize DNA) in vitro.  Here we show that neurotrophin-3 and platelet-derived growth factor collaborate to promote clonal expansion of oligodendrocyte precursor cells in vitro and to drive the intrinsic clock that times oligodendrocyte development6.  We also show that neurotrophin-3 helps stimulate the proliferation of oligodendrocyte precursor cells in vivo and is thus required for normal oligodendrocyte development.
C1 UNIV LONDON UNIV COLL,DEPT BIOL,MRC,DEV NEUROBIOL PROGRAMME,LONDON WC1E 6BT,ENGLAND.
   MAX PLANCK INST PSYCHIAT,DEPT NEUROBIOCHEM,D-82152 PLANEGG,GERMANY.
   BOEHRINGER MANNHEIM,D-82377 PENZBERG,GERMANY.
C3 University of London; University College London; Max Planck Society
NR 29
TC 327
Z9 365
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 371
EP 375
DI 10.1038/367371a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000068
PM 8114937
DA 2026-03-10
ER

PT J
AU RENBERG, I
   PERSSON, MW
   EMTERYD, O
AF RENBERG, I
   PERSSON, MW
   EMTERYD, O
TI PREINDUSTRIAL ATMOSPHERIC LEAD CONTAMINATION DETECTED IN SWEDISH LAKE-SEDIMENTS
SO NATURE
LA English
DT Article
ID deposition; pollution
AB DESPITE evidence from Greenland ice cores for pre-industrial atmospheric trace-metal contamination(1,2) it is commonly assumed that air pollution in remote areas is a recent problem caused by industrial activities, fossil-fuel burning and emissions from motor vehicles. Here we report analyses of lake sediments from Sweden showing that atmospheric lead deposition increased above background levels more than 2,600 years ago. There was a small, but marked lead deposition peak about 2,000 years ago, and a more significant increase that began 1,000 years ago and accelerated during the nineteenth and particularly the twentieth centuries, with a deposition maximum at about AD 1970. Before the nineteenth century industrialization, lead concentrations in lake sediments from southern Sweden had already reached 10-30 times previous background levels as a result of atmospheric deposition. We suggest that this pre-industrial airborne pollution was derived from extensive production and use of lead in Europe, starting with the Greek and Roman cultures(3,4). The cumulative deposition from anthropogenic sources in pre-industrial times (similar to 600 BC to AD 1800) was at least as large as the cumulative deposition during the industrial period (AD 1800 to the present).
C1 UMEA UNIV, DEPT ECOL BOT, S-90187 UMEA, SWEDEN.
   SWEDISH UNIV AGR SCI, ENVIRONM RES LAB, S-90183 UMEA, SWEDEN.
C3 Umea University; Swedish University of Agricultural Sciences
RP RENBERG, I (corresponding author), UMEA UNIV, DEPT ENVIRONM HLTH, S-90187 UMEA, SWEDEN.
NR 19
TC 290
Z9 313
U1 1
U2 76
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 323
EP 326
DI 10.1038/368323a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500042
DA 2026-03-10
ER

PT J
AU HANCOCK, S
   DAVIES, RD
   LASENBY, AN
   DELACRUZ, CMG
   WATSON, RA
   REBOLO, R
   BECKMAN, JE
AF HANCOCK, S
   DAVIES, RD
   LASENBY, AN
   DELACRUZ, CMG
   WATSON, RA
   REBOLO, R
   BECKMAN, JE
TI DIRECT OBSERVATION OF STRUCTURE IN THE COSMIC MICROWAVE BACKGROUND
SO NATURE
LA English
DT Article
ID radio-continuum emission; fluctuations; anisotropy; radiation; scales
AB Temperature fluctuations in the cosmic microwave background are a key prediction of cosmological models of structure formation in the early Universe. Ground-based multi-frequency radio observations of the microwave background reveal well defined features that are not of atmospheric or Galactic origin; instead, they delineate the primordial density perturbations from which the structure in the present Universe originated. The amplitude of these perturbations confirms the earlier statistical detection by the COBE satellite.
C1 INST ASTROFIS CANARIAS,E-38071 LA LAGUNA,SPAIN.
   UNIV CAMBRIDGE,CAVENDISH LAB,MULLARD RADIO ASTRON OBSERV,CAMBRIDGE CB3 0HE,ENGLAND.
C3 Instituto de Astrofisica de Canarias; University of Cambridge
RP HANCOCK, S (corresponding author), UNIV MANCHESTER,NUFFIELD RADIO ASTRON LABS,JODRELL BANK,MACCLESFIELD SK11 9DL,CHESHIRE,ENGLAND.
NR 29
TC 138
Z9 140
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 333
EP 338
DI 10.1038/367333a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000057
DA 2026-03-10
ER

PT J
AU LIUZZI, M
   DEZIEL, R
   MOSS, N
   BEAULIEU, P
   BONNEAU, AM
   BOUSQUET, C
   CHAFOULEAS, JG
   GARNEAU, M
   JARAMILLO, J
   KROGSRUD, RL
   LAGACE, L
   MCCOLLUM, RS
   NAWOOT, S
   GUINDON, Y
AF LIUZZI, M
   DEZIEL, R
   MOSS, N
   BEAULIEU, P
   BONNEAU, AM
   BOUSQUET, C
   CHAFOULEAS, JG
   GARNEAU, M
   JARAMILLO, J
   KROGSRUD, RL
   LAGACE, L
   MCCOLLUM, RS
   NAWOOT, S
   GUINDON, Y
TI A POTENT PEPTIDOMIMETIC INHIBITOR OF HSV RIBONUCLEOTIDE REDUCTASE WITH ANTIVIRAL ACTIVITY IN-VIVO
SO NATURE
LA English
DT Article
ID herpes-simplex virus; colorimetric assay; carboxyl terminus; dna-polymerase; mutants; subunit; type-1; acyclovir; association; sensitivity
AB HERPES simplex viruses (HSV) types 1 and 2 encode their own ribonucleotide reductases (RNRs) (EC 1.17.4.1) to convert ribonucleoside diphosphates into the corresponding deoxyribonucleotides(1). Like other iron-dependent RNRs, the viral enzyme is formed by the reversible association of two distinct homodimeric subunits(2). The carboxy terminus of the RNR small subunit (R2) is critical for subunit association(3,4) and synthetic peptides containing these amino-acid sequences selectively inhibit the viral enzyme by preventing subunit association(4-9). Increasing evidence indicates that the HSV RNR is important for virulence and reactivation from latency(10-14). Previously, we reported on the design of HSV RNR inhibitors with enhanced inhibitory potency in vitro(4,15,16). We now report on BILD 1263, which to our knowledge is the first HSV RNR subunit-association inhibitor with antiviral activity in vivo. This compound suppresses the replication of HSV-1, HSV-2 and acyclovir-resistant HSV strains in cell culture, and also strongly potentiates the antiviral activity of acyclovir. Most importantly, its anti-herpetic activity is shown in a murine ocular model of HSV-1-induced keratitis, providing an example of potent nonsubstrate-based antiviral agents that prevent protein-protein inter actions. The unique antiviral properties of BILD 1263 may lead to the design of new strategies to treat herpesvirus infections in humans.
RP LIUZZI, M (corresponding author), BIO MEGA BOEHRINGER INGELHEIM RES INC,2100 CUNARD ST,LAVAL H7S 2G5,PQ,CANADA.
NR 30
TC 127
Z9 151
U1 0
U2 20
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 695
EP 698
DI 10.1038/372695a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700091
PM 7990963
DA 2026-03-10
ER

PT J
AU YODER, JA
   ACKLESON, SG
   BARBER, RT
   FLAMENT, P
   BALCH, WM
AF YODER, JA
   ACKLESON, SG
   BARBER, RT
   FLAMENT, P
   BALCH, WM
TI A LINE IN THE SEA
SO NATURE
LA English
DT Article
ID eastern equatorial pacific; geostationary satellite; long waves; ocean; oscillations; shelf; front
AB THE ocean has considerable spatial and temporal heterogeneity in biomass and productivity owing in part to the effects of ocean circulation and mixing(1,2). Water mass boundaries (fronts) in coastal waters are well-known sites of enhanced biological activity(3,4). Comparatively little is known of open-ocean fronts, and one of the few biological studies of an oceanic front showed phytoplankton biomass at only slightly higher densities than in surrounding waters(5). Here we present photographs and measurements from satellites, aircraft, ships and the Space Shuttle Atlantis which show dramatic biological responses to circulation and mixing processes associated with an open-ocean front. Breaking waves (whitecaps) caused by water turbulence and mixing, and very dark green water caused by extremely high concentrations (>20 mg of chlorophyll a per m(3)) of buoyant diatoms (Rhizosolenia sp.) made a distinct line in the sea visible for hundreds of kilometres. The line traced the northern edge of a westward-progagating (50 km per day) tropical instability wave (1,000-km wavelength) delineating the boundary between cold, upwelled waters and warmer waters to the north. High phytoplankton biomass and primary production associated with the extensive diatom patches may explain anecdotal observations of high animal abundance along this frontal boundary.
C1 OFF NAVAL RES,OCEAN OPT PROGRAM,ARLINGTON,VA 22217.
   DUKE UNIV,MARINE LAB,BEAUFORT,NC 28516.
   UNIV HAWAII,DEPT OCEANOG,HONOLULU,HI 96822.
   UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149.
C3 United States Department of Defense; United States Navy; Office of Naval Research; Duke University; University of Hawaii System; University of Miami
RP YODER, JA (corresponding author), UNIV RHODE ISL,GRAD SCH OCEANOG,S FERRY RD,NARRAGANSETT,RI 02882, USA.
NR 19
TC 283
Z9 315
U1 0
U2 40
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 689
EP 692
DI 10.1038/371689a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300051
DA 2026-03-10
ER

PT J
AU SCHIANO, P
   CLOCCHIATTI, R
AF SCHIANO, P
   CLOCCHIATTI, R
TI WORLDWIDE OCCURRENCE OF SILICA-RICH MELTS IN SUB-CONTINENTAL AND SUB-OCEANIC MANTLE MINERALS
SO NATURE
LA English
DT Article
ID fluid inclusions; ultramafic xenoliths; lherzolite xenoliths; spinel lherzolite; origin; co2; metasomatism; basalts; island; glass
AB ROCK samples derived from the Earth's upper mantle commonly show indirect evidence for chemical modification. Such modification, or 'metasomatism', can be recognized by the precipitation of exotic minerals such as phlogopite, amphibole or apatite1, and by the overprinting of the bulk compositions of the mantle rocks by a chemical signature involving the enrichment of potassium and other 'incompatible' elements2. Here we study the composition of the metasomatic agents more directly by examining melt and fluid inclusions trapped in mantle minerals. These inclusions are secondary, forming trails along healed fracture planes. A systematic study of the chemical compositions and entrapment temperatures and pressures of inclusions from 14 ultramafic peridotites from both continental and oceanic intraplate regions shows that volatile- and silica-rich metasomatic melts are present throughout the lithosphere. Their compositions, which differ dramatically from those of erupted, mantle-derived magmas, are more akin to continental than to oceanic crust.
C1 CENS,LAB PIERRE SUE,SCI TERRE GRP,F-91191 GIF SUR YVETTE,FRANCE.
C3 CEA; Universite Paris Saclay
RP SCHIANO, P (corresponding author), IPG PARIS,GEOCHIM & COSMOCHIM LAB,4 PL JUSSIEU,F-75252 PARIS 05,FRANCE.
NR 30
TC 211
Z9 220
U1 0
U2 28
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 621
EP 624
DI 10.1038/368621a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200056
DA 2026-03-10
ER

PT J
AU HARMON, JK
   SLADE, MA
   VELEZ, RA
   CRESPO, A
   DRYER, MJ
   JOHNSON, JM
AF HARMON, JK
   SLADE, MA
   VELEZ, RA
   CRESPO, A
   DRYER, MJ
   JOHNSON, JM
TI RADAR MAPPING OF MERCURYS POLAR ANOMALIES
SO NATURE
LA English
DT Article
ID mars; stability; images; ice
AB GROUND-based radar observations of Mercury have revealed unusually strong, highly depolarized echoes from the north(1,2) and south(2) poles. These anomalous echoes have been cited as evidence of polar ice deposits(1-5). Thermal studies(3-5) suggest that the permanently shaded floors of large polar craters are cold enough to preserve water ice in a stable state over aeons, in spite of Mercury's proximity to the Sun. Here we present high-resolution radar maps of Mercury's polar regions, derived from delay-Doppler measurements. We have resolved the north and south polar anomalies into numerous crater-sized features, and we have been able to identify the source craters for many of these features after making small corrections to the pole positions on the Mariner-10 images. The coincidence with crater locations, together with other properties of the radar features, are consistent with the polar-ice hypothesis.
C1 CALTECH,JET PROP LAB,PASADENA,CA 91109.
C3 California Institute of Technology; National Aeronautics & Space Administration (NASA); NASA Jet Propulsion Laboratory (JPL)
RP HARMON, JK (corresponding author), NATL ASTRON & IONOSPHERE CTR,ARECIBO,PR 00613, USA.
NR 10
TC 135
Z9 144
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 213
EP 215
DI 10.1038/369213a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700049
DA 2026-03-10
ER

PT J
AU CONNOLLY, HC
   HEWINS, RH
   ASH, RD
   ZANDA, B
   LOFGREN, GE
   BOUROTDENISE, M
AF CONNOLLY, HC
   HEWINS, RH
   ASH, RD
   ZANDA, B
   LOFGREN, GE
   BOUROTDENISE, M
TI CARBON AND THE FORMATION OF REDUCED CHONDRULES
SO NATURE
LA English
DT Article
ID dynamic crystallization; chondrites; textures; origin; melts
AB CHONDRULES are millimetre-sized spheroidal bodies composed mainly of olivine and orthopyroxene, which comprise the dominant fraction of most chondritic meteorites. They are the products of partial melting of aggregates of fine-grained silicates with minor contributions from metals, sulphides and oxides. Although the formation conditions of chondrules are not well understood, these are thought to involve a transient melting event in the solar nebula(1-3). The ubiquity of reduced carbon in interstellar clouds and primitive meteorites implies that it was also present in the early solar nebula, and may thus have been a potential constituent of chondrule precursor material. We describe here experiments in which carbon and magnesian silicate precursor material of primitive chondrule composition are 'flash-heated' together and then crystallized. The resulting material shows many mineralogical features characteristic of natural chondrules, which are not produced in the absence of carbon(4-12). Our results suggest not only that carbon was present in the solar nebula, but also that it played a key role in chondrule formation by creating within the melt a reducing environment that was decoupled from the nebula gas.
C1 UNIV MANCHESTER,DEPT GEOL,MANCHESTER M13 9PL,LANCS,ENGLAND.
   MUSEUM NATL HIST NAT,MINERAL LAB,F-75005 PARIS,FRANCE.
   INST ASTROPHYS SPATIALE,ORSAY,FRANCE.
   NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058.
C3 University of Manchester; Museum National d'Histoire Naturelle (MNHN); Sorbonne Universite; Universite Paris Saclay; National Aeronautics & Space Administration (NASA); NASA Johnson Space Center
RP CONNOLLY, HC (corresponding author), RUTGERS STATE UNIV,DEPT GEOL SCI,NEW BRUNSWICK,NJ 08903, USA.
NR 29
TC 92
Z9 98
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 136
EP 139
DI 10.1038/371136a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100056
DA 2026-03-10
ER

PT J
AU FARINAS, I
   JONES, KR
   BACKUS, C
   WANG, XY
   REICHARDT, LF
AF FARINAS, I
   JONES, KR
   BACKUS, C
   WANG, XY
   REICHARDT, LF
TI SEVERE SENSORY AND SYMPATHETIC DEFICITS IN MICE LACKING NEUROTROPHIN-3
SO NATURE
LA English
DT Article
ID nerve growth-factor; molecular-cloning; factor family; receptor; neurons; member; system; brain; bdnf; ngf
AB During development, neurotrophins help shape the nervous system by regulating neuronal survival and differentiation. Neurotrophin-3 (refs 1-5) is the most abundant neurotrophin during early development(6). Neurons responsive to neurotrophin-3 in vitro include primary sensory, sympathetic(1-4), motor(7), enteric(1) locus coeruleus(8), hippocampal and cerebellar neurons (ref. 9 for example). Here we report that mice lacking neurotrophin-3 have severe deficits in sensory and sympathetic populations. These mice lack muscle spindles and show abnormal limb positions. In contrast, motor neurons, the enteric nervous system, and the major anatomical regions of the central nervous system seem to develop normally. Comparisons with mutants deficient in other neurotrophins or their receptors(13-15) indicate that some neurons require more than one neurotrophin during embryogenesis and suggest that neurotrophin-3 functions by binding receptors in addition to its primary receptor trkC (ref. 16). In particular, neurotrophin-3 is essential for survival of sympathetic and sensory neurons that later become dependent on nerve growth factor or brain-derived neurotrophic factor.
C1 UNIV CALIF SAN FRANCISCO,SCH MED,HOWARD HUGHES MED INST,SAN FRANCISCO,CA 94143.
C3 Howard Hughes Medical Institute; University of California System; University of California San Francisco
RP FARINAS, I (corresponding author), UNIV CALIF SAN FRANCISCO,SCH MED,DEPT PHYSIOL,PROGRAM NEUROSCI,SAN FRANCISCO,CA 94143, USA.
NR 30
TC 565
Z9 623
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 23
PY 1994
VL 369
IS 6482
BP 658
EP 661
DI 10.1038/369658a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NT459
UT WOS:A1994NT45900058
PM 8208292
DA 2026-03-10
ER

PT J
AU BARONI, MD
   MONTI, P
   ALBERGHINA, L
AF BARONI, MD
   MONTI, P
   ALBERGHINA, L
TI REPRESSION OF GROWTH-REGULATED G1 CYCLIN EXPRESSION BY CYCLIC-AMP IN BUDDING YEAST
SO NATURE
LA English
DT Article
ID saccharomyces-cerevisiae; cell-cycle; positive feedback; signaling pathway; protein-synthesis; s-cerevisiae; size; gene; cln1; division
AB YEAST cell becomes committed to the cell division cycle only if it grows to a critical size(1-4) and reaches a critical rate of protein synthesis(5,6). The coordination between growth and division takes place at a control step during the G1 phase of the cell cycle called Start(4). It relies on the G1-specific cyclins encoded by CLN1, 2 and 3, which trigger Start through the activation of the Cdc28 protein kinase. In fact, the Cln cyclins are rate-limiting for Start execution and depend on growth. Here we report that the cyclic AMP signal pathway(11) modulates the dependency of Cln cyclins on growth. In particular, more growth is required to trigger Start because CLN1 and CLN2 are repressed by the cAMP signal, thus explaining the previously observed cAMP-dependent increase of the critical size and critical rate of protein synthesis(12). Cln3 is not inhibited by the cAMP pathway and counteracts this mechanism by partially mediating the growth-dependent expression of other G1 cyclins.
RP BARONI, MD (corresponding author), UNIV MILAN,DIPARTIMENTO FISIOL & BIOCHIM GEN,BIOCHIM COMPARATA SEZ,VIA CELORIA 26,I-20133 MILAN,ITALY.
NR 31
TC 138
Z9 152
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 339
EP 342
DI 10.1038/371339a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400054
PM 8090203
DA 2026-03-10
ER

PT J
AU GRUNDEMANN, D
   GORBOULEV, V
   GAMBARYAN, S
   VEYHL, M
   KOEPSELL, H
AF GRUNDEMANN, D
   GORBOULEV, V
   GAMBARYAN, S
   VEYHL, M
   KOEPSELL, H
TI DRUG EXCRETION MEDIATED BY A NEW PROTOTYPE OF POLYSPECIFIC TRANSPORTER
SO NATURE
LA English
DT Article
ID basolateral membrane-vesicles; renal brush-border; organic cations; tetraethylammonium; protein; cloning; mechanism; uptake2; rna
AB CATIONIC drugs of different types and structures (antihistaminics, antiarrhythmics, sedatives, opiates, cytostatics and antibiotics, for example) are excreted in mammals by epithelial cells of the renal proximal tubules and by hepatocytes in the liver(1-4). In the proximal tubules, two functionally disparate transport systems are involved which are localized in the basolateral and luminal plasma membrane and are different from the previously identified neuronal monoamine transporters and ATP-dependent multidrug exporting proteins(1-3,5-12). Here we report the isolation of a complementary DNA from rat kidney that encodes a 556-amino-acid membrane protein, OCT1, which has the functional characteristics of organic cation uptake over the basolateral membrane of renal proximal tubules and of organic cation uptake into hepatocytes. OCT1 is not homologous to any other known protein and is found in kidney, liver and intestine. As OCT1 translocates hydrophobic and hydrophilic organic cations of different structures, it is considered to be a new prototype of polyspecific transporters that are important for drug elimination.
C1 UNIV WURZBURG,INST ANAT,D-97070 WURZBURG,GERMANY.
C3 University of Wurzburg
NR 27
TC 583
Z9 653
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 8
PY 1994
VL 372
IS 6506
BP 549
EP 552
DI 10.1038/372549a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PW082
UT WOS:A1994PW08200052
PM 7990927
DA 2026-03-10
ER

PT J
AU MITSUHASHI, M
   COOPER, A
   OGURA, M
   SHINAGAWA, T
   YANO, K
   HOSOKAWA, T
AF MITSUHASHI, M
   COOPER, A
   OGURA, M
   SHINAGAWA, T
   YANO, K
   HOSOKAWA, T
TI OLIGONUCLEOTIDE PROBE DESIGN - A NEW APPROACH
SO NATURE
LA English
DT Article
ID sequence
C1 HITACHI CHEM RES CTR INC,IRVINE,CA 92715.
   DIGITALWORD,BELLEVUE,WA 98008.
   NAGASAKI UNIV,SCH MED,DEPT INTERNAL MED 3,NAGASAKI 852,JAPAN.
   HITACHI CHEM CO LTD,TOKYO,JAPAN.
C3 Hitachi Limited; Nagasaki University; Hitachi Limited
RP MITSUHASHI, M (corresponding author), ADV GENE COMP TECHNOL INC,2102 BUSINESS CTR DR,SUITE 170,IRVINE,CA 92715, USA.
NR 8
TC 46
Z9 55
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 759
EP 761
DI 10.1038/367759a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100064
PM 8107873
DA 2026-03-10
ER

PT J
AU VONGERSDORFF, H
   MATTHEWS, G
AF VONGERSDORFF, H
   MATTHEWS, G
TI DYNAMICS OF SYNAPTIC VESICLE FUSION AND MEMBRANE RETRIEVAL IN SYNAPTIC TERMINALS
SO NATURE
LA English
DT Article
ID transmitter release; nerve-terminals; calcium influx; bipolar cells; capacitance measurements; intracellular calcium; goldfish retina; amino-acids; exocytosis; currents
AB COMMUNICATION among neurons occurs at specialized synaptic junctions, where neurotransmitter is released via calcium-dependent exocytosis from the synaptic terminal of the presynaptic cell onto the postsynaptic target neuron. Here we exploit the unique properties of giant synaptic terminals1-4 of bipolar neurons from goldfish retina to establish the kinetics and calcium-dependence of exocytosis, and the characteristics of membrane retrieval following secretion in presynaptic terminals. Simultaneous patch-clamp, calcium-indicator dye and time-resolved capacitance measurements reveal that activation of calcium current drives secretion at a rapid rate of about 10,000 vesicles per s and the, calcium level necessary to drive secretion is locally greater than 50 muM. Two components of membrane retrieval were observed following secretory stimulation. After strong stimulation, capacitance returned to rest with a time constant of about 30 s, but after weaker stimuli recovery was much faster, with a time constant of about 2 s. Secretion in a vertebrate central nervous system neuron was thus found to differ substantially from that in other secretory cells in its rapid rate of vesicle fusion, requirement for high levels of intracellular calcium, and the high speed and completeness of membrane retrieval. These distinctive features reflect the specialization of neuronal synaptic terminals for rapid and focally directed release of neurotransmitter.
RP VONGERSDORFF, H (corresponding author), SUNY STONY BROOK,DEPT NEUROBIOL & BEHAV,STONY BROOK,NY 11794, USA.
NR 30
TC 394
Z9 424
U1 0
U2 16
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 24
PY 1994
VL 367
IS 6465
BP 735
EP 739
DI 10.1038/367735a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MX631
UT WOS:A1994MX63100058
PM 7906397
DA 2026-03-10
ER

PT J
AU CHIN, YN
   HUANG, YL
AF CHIN, YN
   HUANG, YL
TI IDENTIFICATION OF THE GUEST STAR OF AD-185 AS A COMET RATHER THAN A SUPERNOVA
SO NATURE
LA English
DT Article
ID remnant
AB VERY few nearby supernovae have been bright enough to see with the naked eye. The only such case this century was supernova 1987A. Matching historical records of such events with presently observable remnants allows accurate estimates to be made of the age and incidence rate of supernovae; ancient Chinese astronomical records are a particularly valuable resource for this purpose. The Houhanshu(1) of the Later Han dynasty records the appearance of a 'guest star' in AD 185. This is widely regarded as the oldest supernova recorded historically, and several candidate remnants have been suggested(2,3), in particular the object RCW86(2). Here we show that a reinterpretation of the relevant passage in the Houhanshu is inconsistent with the supernova interpretation, but suggests instead that the guest star was a comet. Our findings indicate that some of the keywords used by Chinese astronomers in historical records must be interpreted with caution.
C1 NATL TSING HUA UNIV,HIST INST,HSINCHU 30043,TAIWAN.
C3 National Tsing Hua University
RP CHIN, YN (corresponding author), UNIV BONN,INST RADIOASTRON,HUGEL 71,D-53121 BONN,GERMANY.
NR 23
TC 28
Z9 32
U1 0
U2 5
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 398
EP 399
DI 10.1038/371398a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500035
DA 2026-03-10
ER

PT J
AU AMIGORENA, S
   DRAKE, JR
   WEBSTER, P
   MELLMAN, I
AF AMIGORENA, S
   DRAKE, JR
   WEBSTER, P
   MELLMAN, I
TI TRANSIENT ACCUMULATION OF NEW CLASS-II MHC MOLECULES IN A NOVEL ENDOCYTIC COMPARTMENT IN B-LYMPHOCYTES
SO NATURE
LA English
DT Article
ID binding protein rab4; invariant chain; antigen presentation; surface expression; t-cells; endosm; transport; complex; peptide; lysosm
AB Endocytosis of antigen by antigen-presenting cells results in the production of peptides that bind to newly synthesized class II molecules of the major histocompatibility complex. A new population of class II-enriched vesicles has been discovered in B lymphocytes that accumulate internalized antigen but are distinct from endosomes and lysosomes. These vesicles also transiently accumulate newly synthesized class II and class II-peptide complexes and appear to be a compartment specialized for the transport and loading of class II molecules.
C1 YALE UNIV, SCH MED, CTR CELL IMAGING, NEW HAVEN, CT 06520 USA.
C3 Yale University
RP AMIGORENA, S (corresponding author), YALE UNIV, SCH MED, DEPT CELL BIOL, 333 CEDAR ST, POB 208002, NEW HAVEN, CT 06520 USA.
NR 38
TC 426
Z9 448
U1 0
U2 4
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAY 12
PY 1994
VL 369
IS 6476
BP 113
EP 120
DI 10.1038/369113a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NK971
UT WOS:A1994NK97100039
PM 8177316
DA 2026-03-10
ER

PT J
AU BEVERIDGE, L
AF BEVERIDGE, L
TI SCIENCE PARKS AS A FORCE IN EMPLOYMENT - CAMBRIDGE-SCIENCE-PARK
SO NATURE
LA English
DT Article
NR 0
TC 0
Z9 1
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 170
EP 171
DI 10.1038/368170a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000075
DA 2026-03-10
ER

PT J
AU DAVISON, W
   ZHANG, H
AF DAVISON, W
   ZHANG, H
TI IN-SITU SPECIATION MEASUREMENTS OF TRACE COMPONENTS IN NATURAL-WATERS USING THIN-FILM GELS
SO NATURE
LA English
DT Article
ID sediment
AB RELIABLE measurement of trace species in natural waters is essential for studies of pollution or trace-element cycling, but is difficult, partly because the distribution of chemical species often changes during sampling and storage1. In situ measurements can overcome these problems, but the few measurements made previously have involved complicated systems that cannot be used routinely1,2. Here we describe a simple technique for measuring trace-metal concentrations in situ in water. The technique incorporates an ion-exchange resin separated from the solution by an ion-permeable gel membrane. Mass transport through the gel is diffusion-controlled and thus well defined, making it possible to obtain quantitative data on concentration and speciation over relatively short time periods (from one hour to several weeks). We present measurements of zinc concentrations in sea water using this technique which agree well with electrochemical measurements. In principle, our technique should be applicable to any inorganic or organic diffusing species.
RP DAVISON, W (corresponding author), UNIV LANCASTER,INST ENVIRONM & BIOL SCI,DIV ENVIRONM SCI,LANCASTER LA1 4YQ,ENGLAND.
NR 12
TC 1086
Z9 1265
U1 11
U2 580
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 546
EP 548
DI 
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300054
DA 2026-03-10
ER

PT J
AU WACKETT, LP
   SADOWSKY, MJ
   NEWMAN, LM
   HUR, HG
   LI, SY
AF WACKETT, LP
   SADOWSKY, MJ
   NEWMAN, LM
   HUR, HG
   LI, SY
TI METABOLISM OF POLYHALOGENATED COMPOUNDS BY A GENETICALLY-ENGINEERED BACTERIUM
SO NATURE
LA English
DT Article
ID toluene dioxygenase; trichloroethylene; oxidation; biosynthesis; degradation; pseudomonas
AB THE decomposition of organic compounds by bacteria has been studied for almost a century1, during which time selective enrichment culture has generated microoganisms capable of metabolizing thousands of organic compounds. But attempts to obtain pure cultures of bacteria that can metabolize highly halogenated compounds2, a large and important class of pollutants 3,4, have been largely unsuccessful. Polyhalogenated compounds are most frequently metabolized by anaerobic bacteria as a result of reductive dehalogenation reactions5, the products of which are typically substrates for bacterial oxygenases6. Complete metabolism of polyhalogenated compounds therefore necessitates the sequential use of anaerobic and aerobic bacteria7. Here we combine seven genes encoding two multi-component oxygenases in a single strain of Pseudomonas which as a result metabolizes polyhalogenated compounds by means of sequential reductive and oxidative reactions to yield non-toxic products. Cytochrome P450(cam) monooxygenase reduces polyhalogenated compounds8, which are bound at the camphor-binding site9,10, under subatmospheric oxygen tensions9. We find that these reduction products are oxidizable substrates for toluene dioxygenase. Perhalogenated chlorofluorocarbons also act as substrates for the genetically engineered strain.
C1 UNIV MINNESOTA,DEPT MICROBIOL,ST PAUL,MN 55108.
   UNIV MINNESOTA,GORTNER LAB,INST ADV STUDIES BIOL PROC TECHNOL,ST PAUL,MN 55108.
   UNIV MINNESOTA,DEPT SOIL SCI,ST PAUL,MN 55108.
C3 University of Minnesota System; University of Minnesota Twin Cities; University of Minnesota System; University of Minnesota Twin Cities; University of Minnesota System; University of Minnesota Twin Cities
RP WACKETT, LP (corresponding author), UNIV MINNESOTA,DEPT BIOCHEM,ST PAUL,MN 55108, USA.
NR 24
TC 69
Z9 84
U1 1
U2 26
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 627
EP 629
DI 10.1038/368627a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200058
PM 8145847
DA 2026-03-10
ER

PT J
AU STEVENS, CF
   WANG, YY
AF STEVENS, CF
   WANG, YY
TI CHANGES IN RELIABILITY OF SYNAPTIC FUNCTION AS A MECHANISM FOR PLASTICITY
SO NATURE
LA English
DT Article
ID long-term potentiation; hippocampal slices; area ca1; probability; depression; recordings; induction; currents; release; neurons
AB SYNAPTIC transmission in the hippocampus is rather unreliable, with many presynaptic action potentials failing to release neurotransmitter(1-4). How is this unreliability affected by the alterations in synaptic strength seen in long-term potentiation (LTP)(5) and long-term depression(6,7) (LTD)? We find that LTP increases synaptic reliability, and LTD decreases it, both without a change in the size of those postsynaptic currents that do occur. Thus LTD is a functional inverse of LTP.
RP STEVENS, CF (corresponding author), SALK INST BIOL STUDIES,HOWARD HUGHES MED INST,MOLEC NEUROBIOL LAB,10010 N TORREY PINES RD,LA JOLLA,CA 92110, USA.
NR 18
TC 326
Z9 349
U1 0
U2 22
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 704
EP 707
DI 10.1038/371704a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300057
PM 7935816
DA 2026-03-10
ER

PT J
AU LORSCH, JR
   SZOSTAK, JW
AF LORSCH, JR
   SZOSTAK, JW
TI IN-VITRO EVOLUTION OF NEW RIBOZYMES WITH POLYNUCLEOTIDE KINASE-ACTIVITY
SO NATURE
LA English
DT Article
ID stranded-dna molecules; invitro selection; rna enzyme; cleavage; recognition; tetrahymena; polymerase; catalysis; sequence; ligands
AB We have isolated a large number of polynucleotide kinase ribozymes from a pool of RNA molecules consisting of an ATP-binding domain flanked by regions of random sequence. Different classes of kinases catalyse the transfer of the gamma-thiophosphate of ATP-gamma S to the 5'-hydroxyl or to internal 2'-hydroxyls. An engineered version of one class is able to catalyse the transfer of thiophosphate from ATP-gamma S to the 5'-hydroxyl of an exogenous oligoribonucleotide substrate with multiple turnover, thus acting as a true enzyme.
C1 HARVARD UNIV, DEPT BIOCHEM & MOLEC BIOL, CAMBRIDGE, MA 02138 USA.
   HARVARD UNIV, SCH MED, DEPT GENET, BOSTON, MA 02115 USA.
C3 Harvard University; Harvard University; Harvard Medical School
RP LORSCH, JR (corresponding author), MASSACHUSETTS GEN HOSP, DEPT MOLEC BIOL, BOSTON, MA 02114 USA.
NR 39
TC 226
Z9 282
U1 0
U2 21
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD SEP 1
PY 1994
VL 371
IS 6492
BP 31
EP 36
DI 10.1038/371031a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PE381
UT WOS:A1994PE38100041
PM 7521014
DA 2026-03-10
ER

PT J
AU DIMARZO, V
   FONTANA, A
   CADAS, H
   SCHINELLI, S
   CIMINO, G
   SCHWARTZ, JC
   PIOMELLI, D
AF DIMARZO, V
   FONTANA, A
   CADAS, H
   SCHINELLI, S
   CIMINO, G
   SCHWARTZ, JC
   PIOMELLI, D
TI FORMATION AND INACTIVATION OF ENDOGENOUS CANNABINOID ANANDAMIDE IN CENTRAL NEURONS
SO NATURE
LA English
DT Article
ID n-acylethanolamine phospholipids; receptor; brain; glycerophospholipids; agonist; binds; cells
AB ANANDAMIDE (N-arachidonoyl-ethanolamine) was recently identified as a brain arachidonate derivative that binds to and activates cannabinoid receptors(1-4), yet the mechanisms underlying formation, release and inactivation of this putative messenger molecule are still unclear. Were we report that anandamide is produced in and released from cultured brain neurons in a calcium ion-dependent manner when the neurons are stimulated with membrane-depolarizing agents. Anandamide formation occurs through phosphodiesterase-mediated cleavage of a novel phospholipid precursor, N-arachidonoyl-phosphatidylethanolamine. A similar mechanism also governs the formation of a family of anandamide congeners, whose possible roles in neuronal signalling remain unknown. Our results and those of others(5,6) indicate therefore that multiple biochemical pathways may participate in anandamide formation in brain tissue. The life span of extracellular anandamide is limited by a rapid and selective process of cellular uptake, which is accompanied by hydrolytic degradation to ethanolamine and arachidonate. Our results thus strongly support the proposed role of anandamide as an endogenous neuronal messenger.
C1 INSERM,CTR PAUL BROCA,UNITE NEUROBIOL & PHARMACOL,PARIS,FRANCE.
   CNR,IST CHIM MOLEC INTERESSE BIOL,NAPLES,ITALY.
C3 Institut National de la Sante et de la Recherche Medicale (Inserm); Consiglio Nazionale delle Ricerche (CNR)
NR 22
TC 1323
Z9 1507
U1 0
U2 44
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 686
EP 691
DI 10.1038/372686a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700089
PM 7990962
DA 2026-03-10
ER

PT J
AU BUCK, WR
   SOKOUTIS, D
AF BUCK, WR
   SOKOUTIS, D
TI ANALOG MODEL OF GRAVITATIONAL COLLAPSE AND SURFACE EXTENSION DURING CONTINENTAL CONVERGENCE
SO NATURE
LA English
DT Article
ID tectonics; deformation; lithosphere; orogens; region; sheet
AB MOST mountain belts occur where continents collide, so it is not surprising that the dominant form of surface deformation is shortening. But there is also abundant geological evidence for extension in the central parts of many mountain belts, at the same time as shortening occurs elsewhere. Previous models for extension require temporal changes in the thermal structure of the lithosphere(1,2), the rate of convergence(2,3), the strength of the crust(3) or the geometry of accretion(4). Here we present a simple model in which no such changes are required for surface extension during the convergent thickening of a viscous 'crustal' layer. Convergence is driven by the motion of two plates at the base of the layer. In the area where one plate 'subducts' under the other, the surface begins to extend soon after the start of convergence, eventually stretching by more then 60 per cent. Extension occurs because gravity drives horizontal flow faster at the free surface than in the centre of a viscous layer that is fixed at its base. In real mountain belts, mid-crustal weaknesses may allow the depth-dependent motion required for surface extension.
C1 COLUMBIA UNIV, DEPT GEOL SCI, PALISADES, NY 10964 USA.
   UPPSALA UNIV, INST EARTH SCI, HANS RAMBERG TECTON LAB, S-75236 UPPSALA, SWEDEN.
C3 Columbia University; Uppsala University
RP BUCK, WR (corresponding author), COLUMBIA UNIV, LAMONT DOHERTY EARTH OBSERV, PALISADES, NY 10964 USA.
NR 17
TC 54
Z9 57
U1 0
U2 9
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 737
EP 740
DI 10.1038/369737a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100057
DA 2026-03-10
ER

PT J
AU BOWCOCK, AM
   RUIZLINARES, A
   TOMFOHRDE, J
   MINCH, E
   KIDD, JR
   CAVALLISFORZA, LL
AF BOWCOCK, AM
   RUIZLINARES, A
   TOMFOHRDE, J
   MINCH, E
   KIDD, JR
   CAVALLISFORZA, LL
TI HIGH-RESOLUTION OF HUMAN EVOLUTIONARY TREES WITH POLYMORPHIC MICROSATELLITES
SO NATURE
LA English
DT Article
ID mitochondrial-dna; populations; persistence; loci
AB GENETIC variation at hypervariable loci is being used extensively for linkage analysis1 and individual identification2, and may be useful for inter-population studies2-5. Here we show that polymorphic microsatellites (primarily CA repeats) allow trees of human individuals to be constructed that reflect their geographic origin with remarkable accuracy. This is achieved by the analysis of a large number of loci for each individual, in spite of the small variations in allele frequencies existing between populations6,7. Reliable evolutionary relationships could also be established in comparisons among human populations but not among great ape species, probably because of constraints on allele length variation. Among human populations, diversity of microsatellites is highest in Africa, which is in contrast to other nuclear markers and supports the hypothesis of an African origin for humans.
C1 STANFORD UNIV, DEPT GENET, STANFORD, CA 94305 USA.
   YALE UNIV, SCH MED, DEPT GENET, NEW HAVEN, CT 06510 USA.
C3 Stanford University; Yale University
RP BOWCOCK, AM (corresponding author), UNIV TEXAS, SW MED CTR, DEPT PEDIAT, 5323 HARRY HINES BLVD, DALLAS, TX 75235 USA.
NR 28
TC 1589
Z9 1768
U1 0
U2 124
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 455
EP 457
DI 10.1038/368455a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000063
PM 7510853
DA 2026-03-10
ER

PT J
AU MOHR, G
   CAPRARA, MG
   GUO, QB
   LAMBOWITZ, AM
AF MOHR, G
   CAPRARA, MG
   GUO, QB
   LAMBOWITZ, AM
TI A TYROSYL-TRANSFER-RNA SYNTHETASE CAN FUNCTION SIMILARLY TO AN RNA STRUCTURE IN THE TETRAHYMENA RIBOZYME
SO NATURE
LA English
DT Article
ID group-i intron; secondary structure; tertiary structure; sequence; core; domain; sites
AB GROUP I introns are highly structured RNAs which catalyse their own splicing by guanosine-initiated transesterification reactions(1,2). Their catalytic core is generally stabilized by RNA-RNA interactions within the core and with peripheral RNA structures(3,4). Additionally, some group I introns require proteins for efficient splicing in vivo(5). The Neurospora CYT-18 protein, the mitochondrial tyrosyl-transfer RNA synthetase (mt TyrRS), promotes splicing of the Neurospora mitochondrial large ribosomal RNA (LSU) and other group I introns by stabilizing the catalytically active structure of the intron core(6-8). We report here that CYT-18 functions similarly to a peripheral RNA structure, P5abc, that stabilizes the catalytic core of the Tetrahymena LSU intron. The CYT-18 protein and P5abc RNA bind to overlapping sites in the intron core, inducing similar conformational changes correlated with splicing activity. Our results show that a protein can play the role of an RNA structure in a catalytic RNA, a substitution postulated for the evolution of nuclear pre-messenger RNA introns from self-splicing introns(9,10).
C1 OHIO STATE UNIV, DEPT MOLEC GENET, COLUMBUS, OH 43210 USA.
   OHIO STATE UNIV, DEPT BIOCHEM, COLUMBUS, OH 43210 USA.
   OHIO STATE UNIV, DEPT MED BIOCHEM, COLUMBUS, OH 43210 USA.
   OHIO STATE UNIV, CTR BIOTECHNOL, COLUMBUS, OH 43210 USA.
C3 University System of Ohio; Ohio State University; University System of Ohio; Ohio State University; University System of Ohio; Ohio State University; University System of Ohio; Ohio State University
NR 28
TC 106
Z9 126
U1 0
U2 1
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 147
EP 150
DI 10.1038/370147a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400059
PM 8022484
DA 2026-03-10
ER

PT J
AU HASSELL, MP
   COMINS, HN
   MAY, RM
AF HASSELL, MP
   COMINS, HN
   MAY, RM
TI SPECIES COEXISTENCE AND SELF-ORGANIZING SPATIAL DYNAMICS
SO NATURE
LA English
DT Article
ID host-parasitoid systems; models; chaos; competition; complexity
AB IN a patchy environment, dispersal between neighbouring local populations can allow the total (regional) population to persist(1-5); even where all patches are identical and the within-patch dynamics are unstable, the total population readily persists as a metapopulation. This persistence is associated with striking, self-organized spatial patterns in the densities of the subpopulations. In the case of hosts and parasitoids, these may form spiral waves, spatial chaos, or a so-called 'crystal lattice' with regularly spaced knots of high population density(4'6). Here we extend earlier work on two species to three or more, showing that coexistence of competing species is usually associated with some degree of persistent spatial segregation, even when the environment is uniform. At its most extreme, this can confine one species to small, relatively static 'islands' within the habitat, giving the appearance of isolated pockets of favourable habitat. The distributions of interacting species may thus result from a trade-off between dispersal and competition within subpopulations, as much as from external factors.
C1 UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED, NERC, CTR POPULAT BIOL, ASCOT SL5 7PY, BERKS, ENGLAND.
   UNIV NEW S WALES, DEPT BIOL SCI, KENSINGTON, NSW 2033, AUSTRALIA.
   UNIV OXFORD, DEPT ZOOL, OXFORD OX1 3PS, ENGLAND.
C3 UK Research & Innovation (UKRI); Natural Environment Research Council (NERC); Imperial College London; University of New South Wales Sydney; University of Oxford
RP HASSELL, MP (corresponding author), UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED, DEPT BIOL, SILWOOD PK, ASCOT SL5 7PY, BERKS, ENGLAND.
NR 27
TC 277
Z9 312
U1 0
U2 64
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 290
EP 292
DI 10.1038/370290a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900062
DA 2026-03-10
ER

PT J
AU VENKATARAMAN, D
   LEE, S
   ZHANG, JS
   MOORE, JS
AF VENKATARAMAN, D
   LEE, S
   ZHANG, JS
   MOORE, JS
TI AN ORGANIC-SOLID WITH WIDE CHANNELS BASED ON HYDROGEN-BONDING BETWEEN MACROCYCLES
SO NATURE
LA English
DT Article
ID molecular recognition; crystal-structure; aggregation; design; acid
AB RESEARCH on microporous solids has focused largely on inorganic materials such as aluminosilicates (zeolites), aluminophosphates, pillared clays and other layered materials(1,2). An elusive goal has been the design of new materials with specific properties such as selective adsorption and catalytic activity. It would be very useful if the tools of molecular synthesis could be brought to bear on this problem. Here we report the design, based on a modular approach, and the crystal structure of an organic solid with large-diameter (about 9 Angstrom) extended channels. The channels are formed from planar, rigid macrocyclic building blocks. Onto the outer rim of the macrocycles are attached phenolic groups, which form hexagonally closest-packed two-dimensional hydrogen-bonded networks. Extended channels result from the stacking of these layers in a way that maintains registry between the macrocyclic cavities, and these channels are filled with solvent molecules. This approach potentially offers a simple means to exercise control over pore size and shape in the solid state.
C1 UNIV MICHIGAN,DEPT CHEM,ANN ARBOR,MI 48109.
   UNIV ILLINOIS,DEPT CHEM,URBANA,IL 61801.
   UNIV ILLINOIS,DEPT MAT SCI & ENGN,URBANA,IL 61801.
C3 University of Michigan System; University of Michigan; University of Illinois System; University of Illinois Urbana-Champaign; University of Illinois System; University of Illinois Urbana-Champaign
NR 27
TC 340
Z9 364
U1 1
U2 50
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 591
EP 593
DI 10.1038/371591a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900046
DA 2026-03-10
ER

PT J
AU HU, SH
   PARKER, MW
   LEI, JY
   WILCE, MCJ
   BENIAN, GM
   KEMP, BE
AF HU, SH
   PARKER, MW
   LEI, JY
   WILCE, MCJ
   BENIAN, GM
   KEMP, BE
TI INSIGHTS INTO AUTOREGULATION FROM THE CRYSTAL-STRUCTURE OF TWITCHIN KINASE
SO NATURE
LA English
DT Article
ID dependent protein-kinase; catalytic subunit; caenorhabditis-elegans; peptide inhibitor; sequence; binding; produce
AB MANY protein kinases are self-regulated by an intrasteric mechanism where part of the enzyme's structure directly inhibits the active site(1,2). This inhibitory structure is called a pseudosubstrate and specific regulators are required to remove it from the active site to allow substrates access. Removal of the pseudosubstrate sequence from members of the myosin light-chain kinase subfamily(1), including twitchin kinase, activates them but it is not known whether the pseudosubtrate sequence binds to the active site. Native twitchin is a 753K protein (6,839 residues) located in muscle A-bands of the nematode Caenorhabditis elegans(3,4) and because of its size has not been easy to study. We have determined the crystal structure, refined to 2.8 Angstrom resolution, of a recombinant fragment (residues 5,890 to 6,262) of twitchin kinase(3,4) that contains the catalytic core and a 60 residue carboxy-terminal tail. The C-terminal tail extends through the active site, wedged between the small and large lobes of the structure and making extensive contacts with the catalytic core which accounts for autoinhibition and provides direct support for the intrasteric mechanism of protein kinase regulation.
C1 ST VINCENTS INST MED RES,FITZROY,VIC 3065,AUSTRALIA.
   EMORY UNIV,DEPT PATHOL,ATLANTA,GA 30322.
C3 St. Vincent's Institute of Medical Research; Emory University
FU Wellcome Trust Funding Source: Medline
NR 22
TC 183
Z9 197
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 581
EP 584
DI 10.1038/369581a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400056
PM 8202162
DA 2026-03-10
ER

PT J
AU HELLER, EJ
   CROMMIE, MF
   LUTZ, CP
   EIGLER, DM
AF HELLER, EJ
   CROMMIE, MF
   LUTZ, CP
   EIGLER, DM
TI SCATTERING AND ABSORPTION OF SURFACE ELECTRON WAVES IN QUANTUM CORRALS
SO NATURE
LA English
DT Article
ID spectroscopy
AB STANDING-WAVE patterns in electron density have been seen recently(1-4) in images of the surfaces of noble metals obtained with the scanning tunnelling microscope (STM). These patterns are due to the scattering of surface electrons off impurities and step edges. By assembling specific enclosed structures of adatoms ('quantum corrals') using the STM, one can generate standing waves of particular geometries(3). Here we describe a theory of the scattering process, which allows us to predict the standing-wave patterns of an arbitrary corral geometry with great accuracy. We can use the theory to examine the scattering properties of the atoms in the corral walls. We find that iron atoms assembled on the (111) surface of copper act as 'black dots', soaking up all of the electron wave amplitude impinging on them. A scattered wave is generated nonetheless, but this behaviour means that the corral walls are only 25% reflective. In an acoustic analogy, the corral is therefore a rather quiet chamber.
C1 HARVARD UNIV,HARVARD SMITHSONIAN OBSERV,CAMBRIDGE,MA 02138.
   IBM CORP,ALMADEN RES CTR,DIV RES,SAN JOSE,CA 95120.
C3 Harvard University; International Business Machines (IBM); IBM USA
RP HELLER, EJ (corresponding author), HARVARD UNIV,DEPT PHYS,17 OXFORD ST,CAMBRIDGE,MA 02138, USA.
NR 9
TC 342
Z9 374
U1 2
U2 141
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 9
PY 1994
VL 369
IS 6480
BP 464
EP 466
DI 10.1038/369464a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NQ286
UT WOS:A1994NQ28600049
DA 2026-03-10
ER

PT J
AU SAHU, KC
AF SAHU, KC
TI STARS WITHIN THE LARGE MAGELLANIC CLOUD AS POTENTIAL LENSES FOR OBSERVED MICROLENSING EVENTS
SO NATURE
LA English
DT Article
ID galactic halo
AB MASSIVE compact objects in the Galactic halo, known as MACHOs, have been postulated as the origin of a substantial fraction of the 'dark matter' known to exist in the haloes of galaxies(1,2). Paczynski(3) has suggested that it might be possible to detect these low-luminosity objects by their potential to act as gravitational lenses, causing a characteristic brightening when they cross the path of light from a star in a nearby galaxy. Very recently, two groups reported possible detections of microlensing of stars in the Large Magellanic Cloud (LMC)(4,5), which was interpreted as a possible fingerprint of MACHOs. Here I show that microlensing by stars within the LMC itself can account for the observed events. In the future it should be possible to distinguish between the two possible sources of microlensing events, however, because events caused by stars in the LMC should be clustered toward the central region of that galaxy,whereas those caused by MACHOs should be uniformly distributed over the whole LMC.
RP SAHU, KC (corresponding author), INST ASTROFIS CANARIAS,E-38200 LA LAGUNA,SPAIN.
NR 24
TC 197
Z9 200
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 275
EP 276
DI 10.1038/370275a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900056
DA 2026-03-10
ER

PT J
AU LIANG, Y
   RICHTER, FM
   WATSON, EB
AF LIANG, Y
   RICHTER, FM
   WATSON, EB
TI CONVECTION IN MULTICOMPONENT SILICATE MELTS DRIVEN BY COUPLED DIFFUSION
SO NATURE
LA English
DT Article
AB THE simplest convecting systems are driven by buoyancy forces arising from the density variations produced by the diffusion of a single quantity, usually heat. In such systems, the necessary condition for the onset of convection is that density decreases downwards. But the convection process can be very different if there are two or more diffusing quantities that affect the density(1-5), a situation often encountered in geological settings. For example, multicomponent convection plays an important role in the convective evolution and differentiation of terrestrial magmas(6-8) A typical terrestrial silicate magma is made up of a number of diffusing components, which not only have different diffusion rates but may also exhibit diffusive coupling-that is, the diffusive flux of one component can be strongly dependent on the spatial gradients of other components(9-12). We have investigated convection in a geologically relevant fluid-a multicomponent silicate melt in the system CaO-Al2O3SiO2-and we find that diffusive coupling plays a key role in promoting convection. Perhaps the most striking feature of these experiments is that convection can occur regardless of whether the density decreases or increases with depth.
C1 RENSSELAER POLYTECH INST,DEPT EARTH & ENVIRONM SCI,TROY,NY 12180.
C3 Rensselaer Polytechnic Institute
RP LIANG, Y (corresponding author), UNIV CHICAGO,DEPT GEOPHYS SCI,CHICAGO,IL 60637, USA.
NR 18
TC 19
Z9 21
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 2
PY 1994
VL 369
IS 6479
BP 390
EP 392
DI 10.1038/369390a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NP174
UT WOS:A1994NP17400053
DA 2026-03-10
ER

PT J
AU KUNDRA, V
   ESCOBEDO, JA
   KAZLAUSKAS, A
   KIM, HK
   RHEE, SG
   WILLIAMS, LT
   ZETTER, BR
AF KUNDRA, V
   ESCOBEDO, JA
   KAZLAUSKAS, A
   KIM, HK
   RHEE, SG
   WILLIAMS, LT
   ZETTER, BR
TI REGULATION OF CHEMOTAXIS BY THE PLATELET-DERIVED GROWTH-FACTOR RECEPTOR-BETA
SO NATURE
LA English
DT Article
ID phospholipase-c-gamma; pdgf receptor; signaling complex; association; binding; sites; gap; phosphorylation; kinase
AB CHEMOTAXIS is an important component of wound healing, development, immunity and metastasis, yet the signalling pathways that mediate chemotaxis are poorly understood. Platelet-derived growth factor (PDGF) acts both as a mitogen and a chemoattractant1. Upon stimulation, the tyrosine kinase PDGF receptor-beta (PDGFR-beta) autophosphorylates2 and forms a complex that includes SH2(Src homology 2)-domain-containing proteins such as the phosphatidylinositol-specific phospholipase C-gamma (ref. 3), Ras-GTPase-activating protein (GAP)4, and phosphatidylinositol-3-OH kinase5. Specific tyrosine-to-phenylalanine substitutions in the PDGFR-beta can prevent binding of one SH2-domain-containing protein without affecting binding of other receptor-associated proteins6,7. Here we use phospholipase C-gamma (ref. 8) and PDGFR-beta mutants9-11 to map specific tyrosines involved in both positive and negative regulation of chemotaxis towards the PDGF-BB homodimer. Our results indicate that a delicate balance of migration-promoting (phospholipase C-gamma and phosphatidylinositol-3-OH kinase) and migration-suppressing (GAP) activities are recruited by the PDGFR-beta to drive chemotaxis towards PDGF-BB.
C1 HARVARD UNIV,CHILDRENS HOSP,SCH MED,300 LONGWOOD AVE,BOSTON,MA 02115.
   UNIV CALIF SAN FRANCISCO,HOWARD HUGHES MED INST,CARDIOVASC RES INST,DEPT MED,SAN FRANCISCO,CA 94143.
   NATL JEWISH CTR IMMUNOL & RESP MED,DENVER,CO 80206.
   NHLBI,BIOCHEM LAB,BETHESDA,MD 20892.
C3 Harvard University; Harvard University Medical Affiliates; Boston Children's Hospital; Harvard Medical School; Howard Hughes Medical Institute; University of California System; University of California San Francisco; National Jewish Health; National Institutes of Health (NIH) - USA; NIH National Heart Lung & Blood Institute (NHLBI)
NR 19
TC 424
Z9 460
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 3
PY 1994
VL 367
IS 6462
BP 474
EP 476
DI 10.1038/367474a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MU679
UT WOS:A1994MU67900058
PM 8107807
DA 2026-03-10
ER

PT J
AU BEEKMAN, EM
   PORCELLI, SA
   MORITA, CT
   BEHAR, SM
   FURLONG, ST
   BRENNER, MB
AF BEEKMAN, EM
   PORCELLI, SA
   MORITA, CT
   BEHAR, SM
   FURLONG, ST
   BRENNER, MB
TI RECOGNITION OF A LIPID ANTIGEN BY CD1-RESTRICTED ALPHA-BETA(+) T-CELLS
SO NATURE
LA English
DT Article
ID lymphocytes-t; cord factor; peptides; biology; genes
AB MAJOR histocompatibility complex (MHC) class I and class II molecules bind immunogenic peptides and present them to lymphocytes bearing the alpha beta T-cell antigen receptor (TCR)(1-4). An analogous antigen-presenting function also has been proposed for the non-MHC-encoded CDI molecules: a family of non-polymorphic, beta(2)-microglobulin-associated glycoproteins(5-8) expressed on most professional antigen-presenting cells(9-11). In support of this hypothesis, CD1 molecules are recognized by selected CD4(-)CD8(-)alpha beta or gamma delta TCR(+) T-cell clones(12-14), and we have recently shown that CD1 molecules restrict the recognition of foreign microbial antigens by alpha beta TCR(+) T cells(10). But the substantial structural divergence of CD1 from MHC class I and class II molecules(7), raises the possibility that the antigens presented by the CD1 system may differ fundamentally from those presented by MHC-encoded molecules. Here we report that a purified CD1b-restricted antigen of Mycobacterium tuberculosis presented to alpha beta TCR(+) T cells is mycolic acid, a family of alpha-branched, beta-hydroxy, long-chain fatty acids found in mycobacteria(15-16). This example of non-protein microbial antigen recognition suggests that alpha beta TCR(+) T cells recognize a broader range of antigens than previously appreciated and that at least one member of the CD1 family has evolved the ability to present lipid antigens.
C1 HARVARD UNIV, SCH MED, BOSTON, MA 02115 USA.
C3 Harvard University; Harvard Medical School
RP BEEKMAN, EM (corresponding author), BRIGHAM & WOMENS HOSP, DEPT RHEUMATOL & IMMUNOL, LYMPHOCYTE BIOL SECT, BOSTON, MA 02115 USA.
NR 30
TC 899
Z9 993
U1 1
U2 20
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 691
EP 694
DI 10.1038/372691a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700090
PM 7527500
DA 2026-03-10
ER

PT J
AU SCHLICHTING, I
   BERENDZEN, J
   PHILLIPS, GN
   SWEET, RM
AF SCHLICHTING, I
   BERENDZEN, J
   PHILLIPS, GN
   SWEET, RM
TI CRYSTAL-STRUCTURE OF PHOTOLYZED CARBONMONOXY-MYOGLOBIN
SO NATURE
LA English
DT Article
ID ligand-binding; heme-proteins; molecular-dynamics; photoproducts; resolution; monoxide; raman; crystallography; diffraction; refinement
AB MYOGLOBIN is a globular haem protein that reversibly binds ligands such as O-2 and CO. Single photons of visible light can break the covalent bond between CO and the haem iron in carbon-monoxy-myoglobin (MbCO) and thus form an unstable intermediate, Mb*CO, with the CO inside the protein(1,2). The ensuing rebinding process has been extensively studied as a model for the interplay of dynamics, structure and function in protein reactions. We have used X-ray crystallography at liquid-helium temperatures to determine the structure of Mb*CO to a resolution of 1.5 Angstrom. The photodissociated CO lies on top of the haem pyrrole ring C. Comparison with the CO-bound and unligated myoglobin structures reveals that on photodissociation of the CO, the haem 'domes', the iron moves partially out of the haem plane, the iron-proximal histidine bond is compressed, the F helix is strained and the distal histidine swings towards the outside of the ligand-binding pocket.
C1 MAX PLANCK INST MED RES,DEPT BIOPHYS,D-69120 HEIDELBERG,GERMANY.
   RICE UNIV,WM KECK CTR COMPUTAT BIOL,HOUSTON,TX 77251.
   BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973.
C3 Max Planck Society; Rice University; United States Department of Energy (DOE); Brookhaven National Laboratory
NR 31
TC 339
Z9 354
U1 1
U2 33
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 27
PY 1994
VL 371
IS 6500
BP 808
EP 812
DI 10.1038/371808a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PP018
UT WOS:A1994PP01800063
PM 7935843
DA 2026-03-10
ER

PT J
AU PARKER, MW
   BUCKLEY, JT
   POSTMA, JPM
   TUCKER, AD
   LEONARD, K
   PATTUS, F
   TSERNOGLOU, D
AF PARKER, MW
   BUCKLEY, JT
   POSTMA, JPM
   TUCKER, AD
   LEONARD, K
   PATTUS, F
   TSERNOGLOU, D
TI STRUCTURE OF THE AEROMONAS TOXIN PROAEROLYSIN IN ITS WATER-SOLUBLE AND MEMBRANE-CHANNEL STATES
SO NATURE
LA English
DT Article
ID site-directed mutagenesis; hole-forming toxin; aerolysin; hydrophila; oligomerization; histidines; monomer; virus
AB AEROLYSIN is chiefly responsible for the pathogenicity of Aeromonas hydrophila, a bacterium associated with diarrhoeal diseases and deep wound infections1. Like many other microbial toxins, the protein changes in a multistep process from a completely water-soluble form to produce a transmembrane channel that destroys sensitive cells by breaking their permeability barriers2. Here we describe the structure of proaerolysin determined by X-ray crystallography at 2.8 angstrom resolution. The protoxin (M(r) 52,000) adopts a novel protein fold. Images of an aerolysin oligomer derived from electron microscopy have assisted in constructing a model of the membrane channel and have led to the proposal of a scheme to account for insertion of the protein into lipid bilayers to form ion channels.
C1 UNIV VICTORIA,DEPT BIOCHEM & MOLEC BIOL,VICTORIA V8W 2Y2,BC,CANADA.
   EUROPEAN MOLEC BIOL LAB,W-6900 HEIDELBERG,GERMANY.
C3 University of Victoria; European Molecular Biology Laboratory (EMBL)
RP PARKER, MW (corresponding author), ST VINCENTS INST MED RES,41 VICTORIA PARADE,FITZROY,VIC 3065,AUSTRALIA.
FU Wellcome Trust Funding Source: Medline
NR 27
TC 386
Z9 415
U1 2
U2 66
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 292
EP 295
DI 10.1038/367292a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400062
PM 7510043
DA 2026-03-10
ER

PT J
AU STUCKEY, JA
   SCHUBERT, HL
   FAUMAN, EB
   ZHANG, ZY
   DIXON, JE
   SAPER, MA
AF STUCKEY, JA
   SCHUBERT, HL
   FAUMAN, EB
   ZHANG, ZY
   DIXON, JE
   SAPER, MA
TI CRYSTAL-STRUCTURE OF YERSINIA PROTEIN-TYROSINE-PHOSPHATASE AT 2.5-ANGSTROM AND THE COMPLEX WITH TUNGSTATE
SO NATURE
LA English
DT Article
ID virulence determinant; purification; intermediate; catalysis; cysteine; charges; lar
AB PROTEIN tyrosine phosphatases (PTPases) and kinases coregulate the critical levels of phosphorylation necessary for intracellular signalling, cell growth and differentiation(1,2). Yersinia, the causative bacteria of the bubonic plague and other enteric diseases, secrete an active PTPase(3), Yop51, that enters and suppresses host immune cells(4,5). Though the catalytic domain is only similar to 20% identical to human PTP1B(6), the Yersinia PTPase contains all of the invariant residues present in eukaryotic PTPases(7), including the nucleophilic Cys 403 which forms a phosphocysteine intermediate during catalysis(3,8-10). We present here structures of the unliganded (2.5 Angstrom resolution) and tungstate-bound (2.6 Angstrom) crystal forms which reveal that Cys 403 is positioned at the centre of a distinctive phosphate-binding loop. This loop is at the hub of several hydrogen-bond arrays that not only stabilize a bound oxyanion, but may activate Cys 403 as a reactive thiolate. Binding of tungstate triggers a conformational change that traps the oxyanion and swings Asp 356, an important catalytic residue(7), by similar to 6 Angstrom into the active site. The same anion-binding loop in PTPases is also found in the enzyme rhodanese(11).
C1 UNIV MICHIGAN,DIV BIOPHYS RES,ANN ARBOR,MI 48109.
   UNIV MICHIGAN,DEPT BIOL CHEM,ANN ARBOR,MI 48109.
   UNIV MICHIGAN,WALTHER CANC INST,ANN ARBOR,MI 48109.
C3 University of Michigan System; University of Michigan; University of Michigan System; University of Michigan; Walther Cancer Foundation; University of Michigan System; University of Michigan
NR 31
TC 386
Z9 436
U1 0
U2 25
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 571
EP 575
DI 10.1038/370571a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700059
PM 8052312
DA 2026-03-10
ER

PT J
AU SACKETT, PD
   MORRISON, HL
   HARDING, P
   BOROSON, TA
AF SACKETT, PD
   MORRISON, HL
   HARDING, P
   BOROSON, TA
TI A FAINT LUMINOUS HALO THAT MAY TRACE THE DARK-MATTER AROUND SPIRAL GALAXY NGC5907
SO NATURE
LA English
DT Article
ID massive halos; clusters; disk
AB THE presence of unseen haloes of 'dark matter' has long been inferred from the high rotation speeds of gas and stars in the outer parts of spiral galaxies(1). The volume density of this dark matter decreases less quickly from the galactic centre than does that of the luminous mass (such as that in stars), meaning that the dark matter dominates the mass far from the centre(1,2). While searching for faint starlight away from the plane of the edge-on spiral galaxy NGC5907 (ref. 3), we have found that the galaxy is surrounded by a faint luminous halo. The intensity of light from this halo falls less steeply than any known luminous component of spiral galaxies, but is consistent with the distribution of dark mass inferred from the galaxy's rotation curve.
C1 NATL OPT ASTRON OBSERV,TUCSON,AZ 85726.
   US GEMINI PROJECT OFF,TUCSON,AZ 85726.
   UNIV ARIZONA,STEWARD OBSERV,TUCSON,AZ 85721.
C3 National Optical Astronomy Observatory; University of Arizona
RP SACKETT, PD (corresponding author), INST ADV STUDY,PRINCETON,NJ 08540, USA.
NR 28
TC 106
Z9 110
U1 0
U2 3
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 11
PY 1994
VL 370
IS 6489
BP 441
EP 443
DI 10.1038/370441a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PB407
UT WOS:A1994PB40700049
DA 2026-03-10
ER

PT J
AU SHAFFER, G
   BENDTSEN, J
AF SHAFFER, G
   BENDTSEN, J
TI ROLE OF THE BERING STRAIT IN CONTROLLING NORTH-ATLANTIC OCEAN CIRCULATION AND CLIMATE
SO NATURE
LA English
DT Article
ID global thermohaline circulation; fresh-water; transports
AB RECENT climate records from ice cores and deep-sea sediments suggest that there has been considerable climate variability in the North Atlantic region over the past 250,000 years1-3. Much of this variability may be linked to changes in thermohaline circulation in the North Atlantic ocean4-6. Model studies7-9 have demonstrated that changes in the flux of fresh water to the ocean, resulting from changes in atmospheric transport or the waxing and waning of ice sheets, can have a significant effect on the thermohaline circulation. Here we present model simulations showing that increased flow of fresher North Pacific water through the Bering Strait into the northern North Atlantic can also affect the thermohaline circulation, by suppressing North Atlantic Deep Water formation; however, decreased flow does not necessarily cause deep-water formation to begin again. In our model, flow through the Bering Strait depends on eustatic sea level and the salinity difference between the North Atlantic and North Pacific oceans. We suggest that the higher sea level during the last interglacial period10, leading to greater flow through the Bering Strait, may have made the North Atlantic thermohaline circulation more sensitive than it is at present to fluctuations in the hydrological cycle, which may explain recent observations1 indicating that climate variability was greater then than it is today.
C1 BORNO INST OCEAN & CLIMATE STUDIES, S-45400 BRASTAD, SWEDEN.
RP SHAFFER, G (corresponding author), UNIV COPENHAGEN, NIELS BOHR INST ASTRON PHYS & GEOPHYS, DEPT GEOPHYS, HARALDSGADE 6, DK-2200 COPENHAGEN, DENMARK.
NR 31
TC 78
Z9 92
U1 0
U2 20
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 354
EP 357
DI 10.1038/367354a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000062
DA 2026-03-10
ER

PT J
AU EDWARDS, G
   LOGAN, R
   COPELAND, M
   REINISCH, L
   DAVIDSON, J
   JOHNSON, B
   MACIUNAS, R
   MENDENHALL, M
   OSSOFF, R
   TRIBBLE, J
   WERKHAVEN, J
   ODAY, D
AF EDWARDS, G
   LOGAN, R
   COPELAND, M
   REINISCH, L
   DAVIDSON, J
   JOHNSON, B
   MACIUNAS, R
   MENDENHALL, M
   OSSOFF, R
   TRIBBLE, J
   WERKHAVEN, J
   ODAY, D
TI TISSUE ABLATION BY A FREE-ELECTRON LASER TUNED TO THE AMIDE-II BAND
SO NATURE
LA English
DT Article
ID absorption; damage
AB EFFORTS to ablate soft tissue with conventional lasers have been limited by collateral damage and by concern over potential photochemical effects(1-5). Motivated by the thermal-confinement model(6), past infrared investigations targeted the OH-stretch mode of water with fast pulses from lasers emitting near 3,000 nm (refs 1, 7-9). What does a free-electron laser offer for the investigation of tissue ablation? Operating at non-photochemical single-photon energies, these infrared sources can produce trains of picosecond pulses tunable to the vibrational modes of proteins, lipids and/or water. We report here that targeting free-electron laser radiation to the amide II band of proteins leads to tissue ablation characterized by minimal collateral damage while maintaining a substantial ablation rate. To account for these observations we propose a novel ablation mechanism based on compromising tissue through resonant denaturation of structural proteins.
C1 VANDERBILT UNIV,SCH MED,DEPT OPHTHALMOL & VISUAL SCI,NASHVILLE,TN 37232.
   VANDERBILT UNIV,SCH MED,DEPT NEUROSURG,NASHVILLE,TN 37232.
   VANDERBILT UNIV,SCH MED,DEPT OTOLARYNGOL,NASHVILLE,TN 37232.
   VANDERBILT UNIV,SCH MED,DEPT PATHOL,NASHVILLE,TN 37232.
C3 Vanderbilt University; Vanderbilt University; Vanderbilt University; Vanderbilt University
RP EDWARDS, G (corresponding author), VANDERBILT UNIV,DEPT PHYS & ASTRON,NASHVILLE,TN 37235, USA.
NR 27
TC 230
Z9 262
U1 2
U2 44
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 416
EP 419
DI 10.1038/371416a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500042
PM 8090220
DA 2026-03-10
ER

PT J
AU KIM, DS
   BONHOEFFER, T
AF KIM, DS
   BONHOEFFER, T
TI REVERSE OCCLUSION LEADS TO A PRECISE RESTORATION OF ORIENTATION PREFERENCE MAPS IN VISUAL-CORTEX
SO NATURE
LA English
DT Article
ID monocular deprivation; striate cortex; functional architecture; intrinsic signals; kittens; cat; organization; selectivity; domains; area-18
AB In the visual system of young kittens, the layout of the cortical maps for ocular dominance and orientation preference converges to an equilibrium state within the first few weeks of life and normally remains largely unchanged. If during the critical period, however, patterned visual experience is restricted to only one eye for a few days, cortical neurons lose their ability to respond to stimulation of the deprived eye. We used the 'reverse occlusion' protocol together with chronical optical imaging to investigate how the profound anatomical changes accompanying monocular deprivation(1) affect the spatial pattern of the cortical orientation preference map. We report here that after 1 week of monocular deprivation, cortical orientation maps for the deprived eye had vanished, But we also discovered that after subsequent reverse occlusion the restored orientation maps were very similar to the original maps. This demonstrates that in spite of functional disconnection of one eye after monocular deprivation, the layout of cortical orientation maps, when re-established for this eye, is not formed from scratch but is strongly influenced by previous experience.
C1 MAX PLANCK INST PSYCHIAT,D-82152 MUNCHEN MARTINSRI,GERMANY.
   MAX PLANCK INST BRAIN RES,D-60528 FRANKFURT,GERMANY.
C3 Max Planck Society; Max Planck Society
NR 19
TC 76
Z9 88
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 370
EP 372
DI 10.1038/370370a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400055
PM 8047142
DA 2026-03-10
ER

PT J
AU KOUVELIOTOU, C
   FISHMAN, GJ
   MEEGAN, CA
   PACIESAS, WS
   VANPARADIJS, J
   NORRIS, JP
   PREECE, RD
   BRIGGS, MS
   HORACK, JM
   PENDLETON, GN
   GREEN, DA
AF KOUVELIOTOU, C
   FISHMAN, GJ
   MEEGAN, CA
   PACIESAS, WS
   VANPARADIJS, J
   NORRIS, JP
   PREECE, RD
   BRIGGS, MS
   HORACK, JM
   PENDLETON, GN
   GREEN, DA
TI THE RARITY OF SOFT GAMMA-RAY REPEATERS DEDUCED FROM REACTIVATION OF SGR1806-20
SO NATURE
LA English
DT Article
ID high-energy transient; supernova
AB ONLY two different types of gamma-ray transient sources are presently known: over one thousand gamma-ray bursters (GRBs) and only three soft gamma-ray repeaters (SGRs). The latter are distinguished by their propensity for recurrent burst behaviour(1-3), in contrast to the nonrepeating GRB sources. Recurrent emission from one of the repeaters, SGR1900+14, has been detected(4) earlier by the Burst and Transient Source Experiment (BATSE) aboard the Compton Gamma-Ray Observatory. Here we report renewed burst activity from SGR1806-20, the most prolific of the three known SGRs. This detection of reactivation of this source has been rapidly followed by identification of an X-ray counterpart(5,6), which also coincides with a compact radio source(7) now identified as a plerionic (pulsar-powered) supernova remnants. In combination, these results are leading to a convergence of ideas about the nature of SGRs, which can now be firmly identified as neutron stars. That BATSE has detected no new sources in its two and a half years of operation indicates that SGRs are rare in our Galaxy.
C1 UNIV SPACE RES ASSOC,HUNTSVILLE,AL 35806.
   UNIV ALABAMA,DEPT PHYS,HUNTSVILLE,AL 35899.
   ASTRON INST ANTON PANNEKOEK,1098 SJ AMSTERDAM,NETHERLANDS.
   CTR HIGH ENERGY ASTROPHYS,1098 SJ AMSTERDAM,NETHERLANDS.
   GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771.
   CAVENDISH LAB,MULLARD RADIO ASTRON OBSERV,CAMBRIDGE CB3 0HE,CAMBS,ENGLAND.
C3 Universities Space Research Association (USRA); University of Alabama System; University of Alabama Huntsville; University of Amsterdam; National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center; University of Cambridge
RP KOUVELIOTOU, C (corresponding author), NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,SPACE SCI LAB,ES66,HUNTSVILLE,AL 35812, USA.
NR 23
TC 128
Z9 131
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 125
EP 127
DI 10.1038/368125a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000057
DA 2026-03-10
ER

PT J
AU ENSOLI, B
   GENDELMAN, R
   MARKHAM, P
   FIORELLI, V
   COLOMBINI, S
   RAFFELD, M
   CAFARO, A
   CHANG, HK
   BRADY, JN
   GALLO, RC
AF ENSOLI, B
   GENDELMAN, R
   MARKHAM, P
   FIORELLI, V
   COLOMBINI, S
   RAFFELD, M
   CAFARO, A
   CHANG, HK
   BRADY, JN
   GALLO, RC
TI SYNERGY BETWEEN BASIC FIBROBLAST GROWTH-FACTOR AND HIV-I TAT PROTEIN IN INDUCTION OF KAPOSIS-SARCOMA
SO NATURE
LA English
DT Article
ID immunodeficiency-virus type-1; melanoma cell invasion; long-term culture; gene-expression; endothelial-cells; basement-membrane; htlv-iii; aids; angiogenesis; collagenase
AB Basic fibroblast growth factor (bFGF) and human immunodeficiency virus type 1 (HIV-1) Tat protein synergize in inducing angiogenic Kaposi's sarcoma-like lesions in mice. Synergy is due to Tat, which enhances endothelial cell growth and type-IV collagenase expression in response to bFGF mimicking extracellular matrix proteins. The bFGF, extracellular Tat and Tat receptors are present in HIV-1-associated KS, which may explain the higher frequency and aggressiveness of this form compared to classical Kaposi's sarcoma where only bFGF is present.
C1 NCI,MOLEC VIROL LAB,BETHESDA,MD 20892.
   ADV BIOSCI LABS INC,KENSINGTON,MD 20895.
   HENRY M JACKSON FDN,ROCKVILLE,MD 20850.
C3 National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI); Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc
RP ENSOLI, B (corresponding author), NCI,TUMOR CELL BIOL LAB,BETHESDA,MD 20892, USA.
NR 43
TC 521
Z9 540
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 20
PY 1994
VL 371
IS 6499
BP 674
EP 680
DI 10.1038/371674a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PM773
UT WOS:A1994PM77300047
PM 7935812
DA 2026-03-10
ER

PT J
AU KOLBER, ZS
   BARBER, RT
   COALE, KH
   FITZWATER, SE
   GREENE, RM
   JOHNSON, KS
   LINDLEY, S
   FALKOWSKI, PG
AF KOLBER, ZS
   BARBER, RT
   COALE, KH
   FITZWATER, SE
   GREENE, RM
   JOHNSON, KS
   LINDLEY, S
   FALKOWSKI, PG
TI IRON LIMITATION OF PHYTOPLANKTON PHOTOSYNTHESIS IN THE EQUATORIAL PACIFIC-OCEAN
SO NATURE
LA English
DT Article
ID marine-phytoplankton; fluorescence; energy; growth; productivity; transport; kinetics; algae
AB THE surface waters of the equatorial Pacific have unusually high nitrate and phosphate concentrations, but relatively low phytoplankton biomass(1-3). This high nitrate, low chlorophyll' (HNLC)(4) Phenomenon has been ascribed to 'top-down' grazing pressure by herbivores, which prevent the phytoplankton from fully utilizing the available nutrients(5). In the late 1980s, however, Martin and co-workers proposed that iron, which is delivered to the remote open ocean in aeolean dust(6), is he key factor limiting the standing crop of phytoplankton in HNLC areas(7,8). Using a sensitive fluorescence method(9), we have followed changes in photochemical energy conversion efficiency(9,10) of the natural phytoplankton community both before and after artificial enrichment with iron of a small area (7.5 x 7.5 km) of the equatorial Pacific Ocean(11). Our results show that iron limits phytoplankton photosynthesis in all size classes in this region bg impairing intrinsic photochemical energy conversion, thereby supporting the hypothesis of physiological ('bottom up') limitation by this element.
C1 DUKE UNIV, MARINE LAB, BEAUFORT, NC 28516 USA.
   MOSS LANDING MARINE LABS, MOSS LANDING, CA 95039 USA.
   MONTEREY BAY AQUARIUM RES INST, PACIFIC GROVE, CA 93950 USA.
C3 Duke University; Moss Landing Marine Laboratories; Monterey Bay Aquarium Research Institute
RP KOLBER, ZS (corresponding author), BROOKHAVEN NATL LAB, DIV OCEANOG & ATMOSPHER SCI, UPTON, NY 11973 USA.
NR 35
TC 321
Z9 358
U1 2
U2 83
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 8
PY 1994
VL 371
IS 6493
BP 145
EP 149
DI 10.1038/371145a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PF191
UT WOS:A1994PF19100060
DA 2026-03-10
ER

PT J
AU ZHUO, M
   HU, YH
   SCHULTZ, C
   KANDEL, ER
   HAWKINS, RD
AF ZHUO, M
   HU, YH
   SCHULTZ, C
   KANDEL, ER
   HAWKINS, RD
TI ROLE OF GUANYLYL CYCLASE AND CGMP-DEPENDENT PROTEIN-KINASE IN LONG-TERM POTENTIATION
SO NATURE
LA English
DT Article
ID cyclic-gmp formation; nitric-oxide; cortical-neurons; involvement; cerebellum; depression; release
AB SEVERAL lines of evidence suggest that cyclic GMP might be involved in long-term potentiation (LTP) in the hippocampus1-6. Arachidonic acid, nitric oxide and carbon monoxide, three molecules that have been proposed to act as retrograde messengers in LTP7-9, all activate soluble guanylyl cyclase1,10,11. We report here that an inhibitor of guanylyl cyclase blocks the induction of LTP in the CA1 region of hippocampal slices. Conversely, cGMP analogues produce long-lasting enhancement of the excitatory postsynaptic potential if they are applied at the same time as weak tetanic stimulation of the presynaptic fibres. The enhancement is spatially restricted, is not blocked by valeric acid (APV), nifedipine, or picrotoxin, and partially occludes LTP. This synaptic enhancement may be mediated by the cGMP-dependent protein kinase (PKG). Inhibitors of PKG block the induction of LTP, and activators of PKG produce activity-dependent long-lasting enhancement. These results suggest that guanylyl cyclase and PKG contribute to LTP, possibly as activity-dependent presynaptic effectors of retrograde messengers.
C1 NEW YORK STATE PSYCHIAT INST & HOSP,NEW YORK,NY 10032.
   HOWARD HUGHES MED INST,NEW YORK,NY 10032.
   UNIV CALIF SAN DIEGO,DEPT PHARMACOL,LA JOLLA,CA 92093.
C3 New York State Psychiatry Institute; Howard Hughes Medical Institute; University of California System; University of California San Diego
RP ZHUO, M (corresponding author), COLUMBIA UNIV COLL PHYS & SURG,CTR NEUROBIOL & BEHAV,NEW YORK,NY 10032, USA.
NR 28
TC 338
Z9 389
U1 0
U2 12
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 635
EP 639
DI 10.1038/368635a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200061
PM 7908417
DA 2026-03-10
ER

PT J
AU VANDERVIES, SM
   GATENBY, AA
   GEORGOPOULOS, C
AF VANDERVIES, SM
   GATENBY, AA
   GEORGOPOULOS, C
TI BACTERIOPHAGE-T4 ENCODES A CO-CHAPERONIN THAT CAN SUBSTITUTE FOR ESCHERICHIA-COLI GROES IN PROTEIN-FOLDING
SO NATURE
LA English
DT Article
ID ribulose bisphosphate carboxylase; morphogenesis; interacts; mutation; gene-31; atp
AB SEVERAL bacteriophages use the Escherichia coli GroES and GroEL chaperonins for folding and assembly of their morphogenetic structures1. Bacteriophage T4 is unusual in that it encodes a specialized protein (Gp31) that is thought to interact with the host GroEL and to be absolutely required for the correct assembly of the major capsid protein (Gp23) in vivo2-4. Here we show that despite the absence of amino-acid sequence similarity between Gp31 and GroES5,6 Gp31 can functionally substitute for the GroES co-chaperonin in the morphogenesis of bacteriophages lambda and T5, the in vivo and in vitro chaperonin-dependent assembly of ribulose bisphosphate carboxylase (Rubisco), as well as overall bacterial growth at the non-permissive temperature. Like GroES, the bacteriophage Gp31 protein forms a stable complex with the E. coli GroEL protein in the presence of Mg-ATP and inhibits the ATPase activity of GroEL in vitro.
C1 DUPONT CO INC,CENT RES & DEV,DIV MOLEC BIOL,EXPTL STN,WILMINGTON,DE 19880.
C3 DuPont; DuPont USA
RP VANDERVIES, SM (corresponding author), UNIV GENEVA,DEPT BIOCHIM MED,CH-1211 GENEVA 4,SWITZERLAND.
NR 19
TC 94
Z9 94
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 654
EP 656
DI 10.1038/368654a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200066
PM 7908418
DA 2026-03-10
ER

PT J
AU SHORE, SN
   STARRFIELD, S
   GONZALEZRIESTRA, R
   HAUSCHILDT, PH
   SONNEBORN, G
AF SHORE, SN
   STARRFIELD, S
   GONZALEZRIESTRA, R
   HAUSCHILDT, PH
   SONNEBORN, G
TI DUST FORMATION IN NOVA-CASSIOPEIAE 1993 SEEN BY ULTRAVIOLET-ABSORPTION
SO NATURE
LA English
DT Article
AB THE clouds of gas in interstellar space also contain grains of dust, whose properties and origins have been the focus of debate for decades. Some dust formation has been assumed to take place in novae explosions(1-5), as was first implied by the observation of a steep decrease in the amount of light emitted by the nova(1,2) DQ Herculis 1934 about 100 days after outburst, presumed to be due to extinction by dust. Here we report observations from the International Ultraviolet Explorer satellite which show directly the onset of dust formation in Nova Cassiopeiae 1993, a classical nova of the same type as DQ Her 1934. The dust formed very quickly-about 70 days after the nova explosion despite the initially high temperature of the ejecta. Our results suggest that high-energy photons are absorbed efficiently by the gas in the ejecta, lowering the temperature in the gas while it is still dense, and thereby allowing molecules to form and then to condense into dust.
C1 ARIZONA STATE UNIV,DEPT PHYS & ASTRON,TEMPE,AZ 85287.
   EUROPEAN SPACE AGCY,ESTEC,DEPT SPACE SCI,DIV ASTROPHYS,VILLAFRANCA,SPAIN.
   EUROPEAN SPACE AGCY,INT ULTRAVIOLET EXPLORER,VILLAFRANCA,SPAIN.
   NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771.
C3 Arizona State University; Arizona State University-Tempe; European Space Agency; European Space Research & Technology Centre; European Space Agency; National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center
RP SHORE, SN (corresponding author), INDIANA UNIV,DEPT PHYS & ASTRON,1700 MISHAWAKA AVE,S BEND,IN 46634, USA.
NR 22
TC 50
Z9 51
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 539
EP 541
DI 10.1038/369539a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400041
DA 2026-03-10
ER

PT J
AU NAEEM, S
   THOMPSON, LJ
   LAWLER, SP
   LAWTON, JH
   WOODFIN, RM
AF NAEEM, S
   THOMPSON, LJ
   LAWLER, SP
   LAWTON, JH
   WOODFIN, RM
TI DECLINING BIODIVERSITY CAN ALTER THE PERFORMANCE OF ECOSYSTEMS
SO NATURE
LA English
DT Article
AB COMMUNITIES of species and their associated biological, chemical and physical processes, collectively known as ecosystems, drive the Earth's biogeochemical processes(1,2). Currently most ecosystems are experiencing loss of biodiversity associated with the activities of human expansion(3-5), raising the issue of whether the biogeochemical functioning of ecosystems will be impaired by this loss of species(6-8). Current ecological knowledge supports a wide range of views on the subject(9-13), but empirical tests are few(9,14-16). Here we provide evidence from direct experimental manipulation of diversity by over an order of magnitude, using multi-trophic level communities and simultaneous measures of several ecosystem processes, that reduced biodiversity may indeed alter the performance of ecosystems.
RP NAEEM, S (corresponding author), UNIV LONDON IMPERIAL COLL SCI & TECHNOL, NERC, CTR POPULAT BIOL, SILWOOD PK, ASCOT SL5 7PY, BERKS, ENGLAND.
NR 28
TC 1292
Z9 1620
U1 6
U2 783
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD APR 21
PY 1994
VL 368
IS 6473
BP 734
EP 737
DI 10.1038/368734a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NG553
UT WOS:A1994NG55300056
DA 2026-03-10
ER

PT J
AU NAIR, APK
   HAHN, S
   BANHOLZER, R
   HIRSCH, HH
   MORONI, C
AF NAIR, APK
   HAHN, S
   BANHOLZER, R
   HIRSCH, HH
   MORONI, C
TI CYCLOSPORINE-A INHIBITS GROWTH OF AUTOCRINE TUMOR-CELL LINES BY DESTABILIZING INTERLEUKIN-3 MESSENGER-RNA
SO NATURE
LA English
DT Article
ID mast-cells; gm-csf; expression; cloning; transformation; activation; invitro; transcription; calcineurin; promoter
AB IN T cells, cyclosporin A (CsA) exerts its immunosuppressive effect by preventing transcriptional induction of the expression of interleukin(IL)-2. This is achieved by a mechanism that involves binding of a CsA-cyclophilin complex to calcineurin, which in turn inhibits the phosphatase-controlled translocation of transcription factor NFAT to the nucleus(1-8). We have previously identified IL-3 as an autocrine oncogenic regulator in tumour cell lines generated by introducing the v-H-ras oncogene into IL-3-dependent mast cells(9-12). Here we report that CsA specifically blocks autocrine tumour cell growth. The mechanism involves down-regulation of IL-3 expression by destabilization of the messenger RNA and requires ongoing transcription. Transcripts from exogenous IL-3 genes lacking the (A + U)-rich element (ARE) in the 3' untranslated terminal repeat could not be destabilized, suggesting that at least part of this sequence, which is known to mediate decay of short-lived mRNA(13), participates in a CsA-sensitive regulatory mechanism.
RP NAIR, APK (corresponding author), UNIV BASEL,INST MED MICROBIOL,PETERSPL 10,CH-4003 BASEL,SWITZERLAND.
NR 28
TC 106
Z9 115
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 239
EP 242
DI 10.1038/369239a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700058
PM 8183344
DA 2026-03-10
ER

PT J
AU WICKMAN, KD
   INIGUEZLLUHI, JA
   DAVENPORT, PA
   TAUSSIG, R
   KRAPIVINSKY, GB
   LINDER, ME
   GILMAN, AG
   CLAPHAM, DE
AF WICKMAN, KD
   INIGUEZLLUHI, JA
   DAVENPORT, PA
   TAUSSIG, R
   KRAPIVINSKY, GB
   LINDER, ME
   GILMAN, AG
   CLAPHAM, DE
TI RECOMBINANT G-PROTEIN BETA-GAMMA-SUBUNITS ACTIVATE THE MUSCARINIC-GATED ATRIAL POTASSIUM CHANNEL
SO NATURE
LA English
DT Article
ID binding regulatory proteins; k+ channels; affinity; prenylation; receptors; membranes; cells; heart
AB ACETYLCHOLINE activates inwardly rectifying potassium channels (I-K.ACh) in the heart(1) through muscarinic receptor binding and activation of pertussis-toxin-sensitive G proteins(2,3). Experiments showing that only the beta gamma-subunit (G beta gamma) activates I-K.ACh (ref. 4) were challenged by reports that only the activated alpha-subunit (G alpha) was effective(5). Here we examine I-K.ACh regulation using purified brain and recombinant G-protein subunits. Six recombinant G beta gamma-subunits activated I-K.ACh with apparent half-maximal activation concentrations of 3-30 nM. Activation of I-K.ACh by recombinant G alpha-GTP gamma S was observed, but this was probably due to release of GTP gamma S from the protein. Importantly, I-K.ACh activity elicited by GTP gamma S was inhibited by purified brain and recombinant G alpha-GDP, suggesting that native G beta gamma plays a major role in this pathway. We conclude that G beta gamma is a primary regulator of I-K.ACh activity.
C1 MAYO CLIN & MAYO FDN,DEPT PHARMACOL,ROCHESTER,MN 55905.
   UNIV TEXAS,SW MED CTR,DALLAS,TX 75235.
C3 Mayo Clinic; University of Texas System; University of Texas Southwestern Medical Center; University of Texas Dallas
NR 17
TC 406
Z9 468
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 255
EP 257
DI 10.1038/368255a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000059
PM 8145826
DA 2026-03-10
ER

PT J
AU BURMEISTER, WP
   HUBER, AH
   BJORKMAN, PJ
AF BURMEISTER, WP
   HUBER, AH
   BJORKMAN, PJ
TI CRYSTAL-STRUCTURE OF THE COMPLEX OF RAT NEONATAL FC RECEPTOR WITH FC
SO NATURE
LA English
DT Article
ID 3-dimensional structure; immunoglobulin-g; newborn rat; intestine; binding; crystallization; expression; refinement; transport; fragment
AB THE neonatal Fc receptor (FcRn) transports maternal immunoglobulin G (IgG) to the bloodstream of the newborn. FcRn is structurally similar to class I major histocompatibility complex (MHC) molecules(1,2), despite differences in the ligands they bind (the Fc portion of IgG and antigenic peptides, respectively). A low-resolution crystal structure of the complex between FcRn and Fc localizes the binding site for Fc to the side of FcRn, distinct from the tops of the alpha 1 and alpha 2 domains which serve as the peptide and T-cell receptor binding sites in class I molecules. FcRn binds to Fc at the interface between the Fc C(H)2 and C(H)3 domains, which contains several histidine residues that could account for the sharply pH-dependent FcRn/IgG interaction(3). A dimer of FcRn heterodimers observed in the co-crystals and in the crystals of FcRn alone(2) could be involved in binding Fc, correlating with the 2:1 binding stoichiometry between FcRn and IgG (ref. 4) and suggesting an unusual orientation of FcRn on the membrane.
C1 CALTECH,HOWARD HUGHES MED INST,PASADENA,CA 91125.
   CALTECH,DIV BIOL 15629,PASADENA,CA 91125.
C3 California Institute of Technology; Howard Hughes Medical Institute; California Institute of Technology
NR 28
TC 411
Z9 681
U1 0
U2 25
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 24
PY 1994
VL 372
IS 6504
BP 379
EP 383
DI 10.1038/372379a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PU287
UT WOS:A1994PU28700060
PM 7969498
DA 2026-03-10
ER

PT J
AU FANTL, WJ
   MUSLIN, AJ
   KIKUCHI, A
   MARTIN, JA
   MACNICOL, AM
   GROSS, RW
   WILLIAMS, LT
AF FANTL, WJ
   MUSLIN, AJ
   KIKUCHI, A
   MARTIN, JA
   MACNICOL, AM
   GROSS, RW
   WILLIAMS, LT
TI ACTIVATION OF RAF-1 BY 14-3-3-PROTEINS
SO NATURE
LA English
DT Article
ID kinase-kinase; oocyte maturation; expression; induction; pathway; cloning; growth; cyclin; family; cells
AB THE protein Raf-1, a key mediator of mitogenesis and differentiation, associates with p21(ras) (refs 1-3). However, the regulation of the serine/threonine kinase activity of Raf-1 is still not understood(4-13). Using the yeast two-hybrid systems(8,14-16), we identified two structurally related proteins that interact with the aminoterminal region of Raf-1. These proteins, 14-3-3 zeta (PLA(2)) and 14-3-3 beta (HS1), are members of the 14-3-3 family of proteins(17-23). Expression of 14-3-3 proteins in Xenopus oocytes enhanced Raf-1 activity and promoted Raf-1-dependent oocyte maturation. A dominant negative mutant of Raf-1 blocked the effects of 14-3-3 protein.
C1 WASHINGTON UNIV, SCH MED, DIV BIOORGAN CHEM & MOLEC PHARMACOL, ST LOUIS, MO 63110 USA.
C3 Washington University (WUSTL)
RP FANTL, WJ (corresponding author), UNIV CALIF SAN FRANCISCO, DAIICHI RES CTR, INST CARDIOVASC RES, DEPT MED, SAN FRANCISCO, CA 94143 USA.
NR 30
TC 335
Z9 358
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 13
PY 1994
VL 371
IS 6498
BP 612
EP 614
DI 10.1038/371612a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PL559
UT WOS:A1994PL55900054
PM 7935795
DA 2026-03-10
ER

PT J
AU REUVENY, E
   SLESINGER, PA
   INGLESE, J
   MORALES, JM
   INIGUEZLLUHI, JA
   LEFKOWITZ, RJ
   BOURNE, HR
   JAN, YN
   JAN, LY
AF REUVENY, E
   SLESINGER, PA
   INGLESE, J
   MORALES, JM
   INIGUEZLLUHI, JA
   LEFKOWITZ, RJ
   BOURNE, HR
   JAN, YN
   JAN, LY
TI ACTIVATION OF THE CLONED MUSCARINIC POTASSIUM CHANNEL BY G-PROTEIN BETA-GAMMA-SUBUNITS
SO NATURE
LA English
DT Article
ID coupled receptor kinases; k+-channel; ion channels; mechanism; expression; alpha; cloning; cyclase; heart
AB ACETYLCHOLINE released during parasympathetic stimulation of the vagal nerve slows the heart rate through the activation of muscarinic receptors and subsequent opening of an inwardly rectifying potassium channel(1) The activation of these muscarinic potassium channels is mediated by a pertussis toxin-sensitive heterotrimeric GTP-binding protein (G protein)(2,3). It has not been resolved whether exogenously applied G(alpha)(4,5) or G(beta gamma)(6,7), Or both, activate the channel. Using a heterologous expression system, we have tested the ability of different G protein subunits to activate the cloned muscarinic potassium channel, GIRK1(8,9). We report here that coexpression of GIRK1 with G(beta gamma) but not G(alpha beta gamma) in Xenopus oocytes results in channel activity that persists in the absence of cytoplasmic GTP. This activity is reduced by fusion proteins of the beta-adrenergic receptor kinase and of recombinant G(alpha i)-GDP, both of which are known to interact with G(beta gamma)(10,11). Moreover, application of recombinant G(beta gamma), but not G(alpha i)-GTP-gamma S, activates GIRK1 channels. Thus G(beta gamma) appears to be sufficient for the activation of GIRK1 muscarinic potassium channels.
C1 UNIV CALIF SAN FRANCISCO,DEPT PHYSIOL,SAN FRANCISCO,CA 94143.
   UNIV CALIF SAN FRANCISCO,DEPT BIOCHEM,SAN FRANCISCO,CA 94143.
   DUKE UNIV,MED CTR,HOWARD HUGHES MED INST,DURHAM,NC 27710.
   DUKE UNIV,MED CTR,DEPT MED,DURHAM,NC 27710.
   DUKE UNIV,MED CTR,DEPT BIOCHEM,DURHAM,NC 27710.
   UNIV CALIF SAN FRANCISCO,DEPT PHARMACOL,SAN FRANCISCO,CA 94143.
   UNIV TEXAS,SW MED CTR,DEPT PHARMACOL,DALLAS,TX 75235.
C3 University of California System; University of California San Francisco; University of California System; University of California San Francisco; Duke University; Howard Hughes Medical Institute; Duke University; Duke University; University of California System; University of California San Francisco; University of Texas System; University of Texas Dallas; University of Texas Southwestern Medical Center
RP REUVENY, E (corresponding author), UNIV CALIF SAN FRANCISCO,HORMONE RES INST,SAN FRANCISCO,CA 94143, USA.
NR 30
TC 446
Z9 513
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 14
PY 1994
VL 370
IS 6485
BP 143
EP 146
DI 10.1038/370143a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NW804
UT WOS:A1994NW80400058
PM 8022483
DA 2026-03-10
ER

PT J
AU STOUFFER, RJ
   MANABE, S
   VINNIKOV, KY
AF STOUFFER, RJ
   MANABE, S
   VINNIKOV, KY
TI MODEL ASSESSMENT OF THE ROLE OF NATURAL VARIABILITY IN RECENT GLOBAL WARMING
SO NATURE
LA English
DT Article
ID ocean atmosphere model; transient responses; gradual changes; co2
AB SINCE the late nineteenth century, the global mean surface air temperature has been increasing at the rate of about 0.5 degrees C per century(1-3), but our poor understanding of low-frequency natural climate variability has made it very difficult to determine whether the observed warming trend is attributable to the enhanced greenhouse effect associated with increased atmospheric concentrations of greenhouse gases(4,5). Here we evaluate the observed warming trend using a 1,000-year time series of global temperature obtained from a mathematical model of the coupled ocean-atmosphere-land system. We find that the model approximately reproduces the magnitude of the annual to interdecadal variation in global mean surface air temperature. But throughout the simulated time series no temperature change as large as 0.5 degrees C per century is sustained for more than a few decades. Assuming that the model is realistic, these results suggest that the observed trend is not a natural feature of the interaction between the atmosphere and oceans. Instead, it may have been induced by a sustained change in the thermal forcing, such as that resulting from changes in atmospheric greenhouse gas concentrations and aerosol loading.
RP STOUFFER, RJ (corresponding author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08542, USA.
NR 17
TC 120
Z9 127
U1 1
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 634
EP 636
DI 10.1038/367634a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800050
DA 2026-03-10
ER

PT J
AU COHENTANNOUDJI, M
   BABINET, C
   WASSEF, M
AF COHENTANNOUDJI, M
   BABINET, C
   WASSEF, M
TI EARLY DETERMINATION OF A MOUSE SOMATOSENSORY CORTEX MARKER
SO NATURE
LA English
DT Article
ID cerebral-cortex; visual-cortex; specification; neocortex; neurons; rat; organization; units; lacz
AB THE mammalian neocortex is subdivided into functionally distinct areas differing in cytoarchitecture and connectivity. Areal specification is thought to occur late in development1-3 and to be controlled by extrinsic cues, particularly thalamic afferents4. We have produced a transgenic mouse line in which beta-galactosidase expression in the neocortex is largely restricted to layer-IV neurons of the somatosensory area. Transgene expression in these mice may be considered as an intrinsic marker of a somatosensory cortex identity. We investigated whether the fate of pieces of embryonic cortex from transgenic embryos is modified after transplantation to ectopic locations. Parietal or occipital cortex obtained on embryonic days 14-16 maintained their characteristics with respect to transgene expression after heterotopic transplantation to the cerebellum or neocortex of newborn hosts. This shows that the specification of neocortical areas involves a previously unsuspected early step of areal determination.
C1 HOP LA PITIE SALPETRIERE,INSERM,U106,F-75651 PARIS 13,FRANCE.
   INST PASTEUR,F-75724 PARIS 15,FRANCE.
C3 Assistance Publique Hopitaux Paris (APHP); Hopital Universitaire Pitie-Salpetriere - APHP; Institut National de la Sante et de la Recherche Medicale (Inserm); Sorbonne Universite; Pasteur Network; Universite Paris Cite; Institut Pasteur Paris
NR 18
TC 174
Z9 179
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 460
EP 463
DI 10.1038/368460a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000065
PM 8133892
DA 2026-03-10
ER

PT J
AU BARNES, JR
   STEPHENSON, RJ
   WELLAND, ME
   GERBER, C
   GIMZEWSKI, JK
AF BARNES, JR
   STEPHENSON, RJ
   WELLAND, ME
   GERBER, C
   GIMZEWSKI, JK
TI PHOTOTHERMAL SPECTROSCOPY WITH FEMTOJOULE SENSITIVITY USING A MICROMECHANICAL DEVICE
SO NATURE
LA English
DT Article
ID force microscope cantilevers
AB WHEN a material absorbs a photon, a fraction of the energy may be transformed into heat. A measurement of photothermal heating as a function of wavelength can provide an absorption spectrum of the material. We have recently(1,2) developed a micromechanical sensor capable of detecting heat changes of the order of picojoules (10(-12) J). The instrument incorporates a bilayer cantilever of micrometre dimensions which bends in response to heating. Here we show that this device can be used for photothermal spectroscopy with a power sensitivity of 100 pW-two orders of magnitude better than the sensitivity of conventional photothermal deflection spectroscopy(3). The small size of the sensor allows picogram quantities of material to be studied, opening up the possibility of spectroscopic studies on individual cells and bacteria. Being based on silicon technology, the sensor should be compatible with microelectronic circuitry.
C1 IBM CORP,DIV RES,ZURICH RES LAB,CH-8803 RUSCHLIKON,SWITZERLAND.
C3 International Business Machines (IBM); IBM Switzerland
RP BARNES, JR (corresponding author), UNIV CAMBRIDGE,DEPT ENGN,TRUMPINGTON ST,CAMBRIDGE CB2 1PZ,ENGLAND.
NR 14
TC 278
Z9 332
U1 2
U2 73
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 79
EP 81
DI 10.1038/372079a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800074
DA 2026-03-10
ER

PT J
AU HUO, QS
   MARGOLESE, DI
   CIESLA, U
   FENG, PY
   GIER, TE
   SIEGER, P
   LEON, R
   PETROFF, PM
   SCHUTH, F
   STUCKY, GD
AF HUO, QS
   MARGOLESE, DI
   CIESLA, U
   FENG, PY
   GIER, TE
   SIEGER, P
   LEON, R
   PETROFF, PM
   SCHUTH, F
   STUCKY, GD
TI GENERALIZED SYNTHESIS OF PERIODIC SURFACTANT INORGANIC COMPOSITE-MATERIALS
SO NATURE
LA English
DT Article
ID cubic phases; systems
AB THE recent synthesis of silica-based mesoporous materials(1,2) by the cooperative assembly of periodic inorganic and surfactant-based structures has attracted great interest because it extends the range of molecular-sieve materials into the very-large-pore regime. If the synthetic approach can be generalized to transition-metal oxide mesostructures, the resulting nanocomposite materials might find applications in electrochromic or solid-electrolyte devices(3,4), as high-surface-area redox catalysts(5) and as substrates for biochemical separations. We have proposed recently(6) that the matching of charge density at the surfactant/inorganic interfaces governs the assembly process; such co-organization of organic and inorganic phases is thought to be a key aspect of biomineralization(7). Here we report a generalized approach to the synthesis of periodic mesophases of metal oxides and cationic or anionic surfactants under a range of pH conditions. We suggest that the assembly process is controlled by electrostatic complementarity between the inorganic ions in solution, the charged surfactant head groups and-when these charges both have the same sign-inorganic counterions. We identify a number of different general strategies for obtaining a variety of ordered composite materials.
C1 UNIV CALIF SANTA BARBARA, DEPT CHEM, SANTA BARBARA, CA 93106 USA.
   JOHANNES GUTENBERG UNIV, INST ANORGAN CHEM, D-55099 MAINZ, GERMANY.
   UNIV CALIF SANTA BARBARA, CTR QUANTIZED ELECTR STRUCT, SANTA BARBARA, CA 93106 USA.
C3 University of California System; University of California Santa Barbara; Johannes Gutenberg University of Mainz; University of California System; University of California Santa Barbara
NR 26
TC 1961
Z9 2283
U1 6
U2 803
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 317
EP 321
DI 10.1038/368317a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500040
DA 2026-03-10
ER

PT J
AU SENAY, MC
   JEWITT, D
AF SENAY, MC
   JEWITT, D
TI COMA FORMATION DRIVEN BY CARBON-MONOXIDE RELEASE FROM COMET SCHWASSMANN-WACHMANN-1
SO NATURE
LA English
DT Article
ID p/schwassmann-wachmann-1; dust; ice; nuclei; excitation; gas; cn
AB DISTANT comets are sometimes observed to undergo outbursts of activity that generate a surrounding coma, but the cause of this activity is not known(1,2). Whereas such outbursts in near-Sun comets are driven by the sublimation of water ice(3), distant comets are too cold for this process to operate. The most plausible mechanisms involve the release of trapped gases from ice heated by an exothermic phase transition from an amorphous to a crystalline state(4-6), or the sublimation of very volatile ices such as molecular nitrogen and carbon monoxide(7-9). Here we report the detection of emission from carbon monoxide at submillimetre wavelengths from a distant comet, the periodic comet Schwassmarn-Wachmann 1. The inferred rate of CO production is sufficient to generate the observed coma. These results provide the first direct evidence that sublimation of volatiles can drive the activity of distant comets.
RP SENAY, MC (corresponding author), UNIV HAWAII, INST ASTRON, 2680 WOODLAWN DR, HONOLULU, HI 96822 USA.
NR 32
TC 117
Z9 121
U1 1
U2 4
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 229
EP 231
DI 10.1038/371229a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000045
DA 2026-03-10
ER

PT J
AU HERMER, L
   SPELKE, ES
AF HERMER, L
   SPELKE, ES
TI A GEOMETRIC PROCESS FOR SPATIAL REORIENTATION IN YOUNG-CHILDREN
SO NATURE
LA English
DT Article
ID rats
AB DISORIENTED(1-3) rats and non-human primates reorient themselves using geometrical features of the environment(2,4-6). In rats tested in environments with distinctive geometry, this ability is impervious to non-geometric information (such as colours and odours) marking important locations and used in other spatial tasks'. Here we show that adults use both geometric and non-geometric information to reorient themselves, whereas young children, like mature rats, use only geometric information. These findings provide evidence that: (1) humans reorient in accord with the shape of the environment; (2) the young child's reorientation system is impervious to all but geometric information(8), even when non-geometric information is available and is re-presented by the child-such information should improve performance and is used in similar tasks by the oriented child; and (3) the limits of this process are overcome during human development.
C1 CORNELL UNIV,COGNIT STUDIES PROGRAM,ITHACA,NY 14853.
C3 Cornell University
RP HERMER, L (corresponding author), CORNELL UNIV,DEPT PSYCHOL,URIS HALL,ITHACA,NY 14853, USA.
NR 14
TC 511
Z9 563
U1 0
U2 61
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 57
EP 59
DI 10.1038/370057a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100057
PM 8015605
DA 2026-03-10
ER

PT J
AU ZHANG, GH
   TANEJA, KL
   SINGER, RH
   GREEN, MR
AF ZHANG, GH
   TANEJA, KL
   SINGER, RH
   GREEN, MR
TI LOCALIZATION OF PRE-MESSENGER-RNA SPLICING IN MAMMALIAN NUCLEI
SO NATURE
LA English
DT Article
ID insitu hybridization; nascent transcripts; cell-nucleus; poly(a) rna; ribonucleoproteins; organization; identification; domains; protein; interphase
AB IN mammalian nuclei, precursor messenger RNA splicing factors are distributed non-uniformly. Antibodies directed against structural polypeptides of small nuclear ribonucleoprotein particles (snRNPs)(1) and some non-snRNP splicing factors(2) have shown that these components are concentrated in about 20-50 nuclear 'speckles'. These and other non-homogeneous distributions have been proposed to indicate nuclear 'compartments' that are distinct from the sites of transcription and in which RNA processing (3-9). We have tested this idea using a new approach. Previous structural(10-13) and biochemical(14-16) data have shown that splicing can occur in association with transcription. Nascent RNA of specific genes can be detected by in situ hybridization as intense spots of nuclear stain which map to the sites of transcription(17-19). Here we identify active pre-mRNA splicing sites by localizing the nascent spliced mRNA of specific genes. We find that splicing occurs at the sites of transcription, which are not coincident with intranuclear speckles. We conclude that the nucleus is not compartmentalized with respect to transcription and pre-mRNA splicing.
C1 UNIV MASSACHUSETTS,MED CTR,DEPT CELL BIOL,WORCESTER,MA 01605.
C3 University of Massachusetts System; University of Massachusetts Worcester
RP ZHANG, GH (corresponding author), UNIV MASSACHUSETTS,MED CTR,HOWARD HUGHES MED INST,PROGRAM MOLEC MED,373 PLANTAT ST,WORCESTER,MA 01605, USA.
NR 30
TC 234
Z9 259
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 22
PY 1994
VL 372
IS 6508
BP 809
EP 812
DI 
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PY212
UT WOS:A1994PY21200061
PM 7997273
DA 2026-03-10
ER

PT J
AU STEIN, M
   HOFMANN, AW
AF STEIN, M
   HOFMANN, AW
TI MANTLE PLUMES AND EPISODIC CRUSTAL GROWTH
SO NATURE
LA English
DT Article
ID nd-isotopic evidence; large-scale structure; sm-nd; continental-crust; northwest pacific; western-australia; greenstone belts; earths mantle; oceanic-crust; mid-continent
AB Many hitherto puzzling features of the isotope and trace-element geochemistry of the Earth's mantle and crust can be explained if Earth history is punctuated by episodes of enhanced exchange between the lower and upper mantle. Such episodes would replenish the upper mantle with trace elements, and also cause rapid growth of continental crust. This picture is consistent with recent geophysical models in which two-layer convection alternates with episodes of penetrative or whole-mantle convection.
C1 MAX PLANCK INST CHEM, D-55020 MAINZ, GERMANY.
C3 Max Planck Society
RP STEIN, M (corresponding author), HEBREW UNIV JERUSALEM, INST EARTH SCI, IL-91904 JERUSALEM, ISRAEL.
NR 73
TC 420
Z9 464
U1 1
U2 77
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 3
PY 1994
VL 372
IS 6501
BP 63
EP 68
DI 10.1038/372063a0
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ348
UT WOS:A1994PQ34800070
DA 2026-03-10
ER

PT J
AU KOLESKE, AJ
   YOUNG, RA
AF KOLESKE, AJ
   YOUNG, RA
TI AN RNA POLYMERASE-II HOLOENZYME RESPONSIVE TO ACTIVATORS
SO NATURE
LA English
DT Article
ID transcription factor; saccharomyces-cerevisiae; terminal domain; initiation; purification; promoter; invitro; phosphorylation; identification; complexes
AB RNA POLYMERASE II requires multiple general transcription factors to initiate site-specific transcription1-3.  These proteins can assemble in an ordered fashion onto promoter DNA in vitro2-8, and such ordered assembly may occur in vivo (Fig. 1a). Some general transcription factors can interact with RNA polymerase II in the absence of DNA3,9-15, however, suggesting that RNA polymerase II may also assemble into a multi-component complex containing a subset of initiation factors before binding to promoter DNA (Fig. 1b). Here we present evidence from the yeast Saccharomyces cerevisiae for such an RN.A polymerase II holoenzyme, a multi-subunit complex containing roughly equimolar amounts of RNA polymerase II, a subset of general transcription factors, and SRB regulatory proteins. Transcription by this holoenzyme is stimulated by the activator protein GAL4-VP16, a feature not observed with purified RNA polymerase II and general transcription factors alone. We propose that the holoenzyme is a form of RNA polymerase II readily recruited to promoters in vivo.
C1 MIT,DEPT BIOL,CAMBRIDGE,MA 02139.
C3 Massachusetts Institute of Technology (MIT)
RP KOLESKE, AJ (corresponding author), WHITEHAD INST BIOMED RES,9 CAMBRIDGE CTR,CAMBRIDGE,MA 02142, USA.
NR 30
TC 557
Z9 625
U1 0
U2 13
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 31
PY 1994
VL 368
IS 6470
BP 466
EP 469
DI 10.1038/368466a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ND120
UT WOS:A1994ND12000067
PM 8133894
DA 2026-03-10
ER

PT J
AU COLVIN, VL
   SCHLAMP, MC
   ALIVISATOS, AP
AF COLVIN, VL
   SCHLAMP, MC
   ALIVISATOS, AP
TI LIGHT-EMITTING-DIODES MADE FROM CADMIUM SELENIDE NANOCRYSTALS AND A SEMICONDUCTING POLYMER
SO NATURE
LA English
DT Article
ID electroluminescence; emission
AB Electroluminescent devices have been developed recently that are based on new materials such as porous silicon and semiconducting polymers(2,3). By taking advantage of developments in the preparation and characterization of direct-gap semiconductor nanocrystals(4-6), and of electroluminescent polymers', we have now constructed a hybrid organic/inorganic electroluminescent device. Light emission arises from the recombination of holes injected into a layer of semiconducting p-paraphenylene vinylene (PPV)(8-10) with electrons injected into a multilayer film of cadmium selenide nanocrystals. Close matching of the emitting layer of nanocrystals with the work function of the metal contact leads to an operating voltage(11) of only 4 V. At low voltages emission from the CdSe layer occurs. Because of the quantum size effect(19-24) the colour of this emission can be varied from red to yellow by changing the nanocrystal size. At higher voltages green emission from the polymer layer predominates. Thus this device has a degree of voltage tunability of colour.
C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720.
C3 University of California System; University of California Berkeley
RP COLVIN, VL (corresponding author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720, USA.
NR 26
TC 4046
Z9 4611
U1 17
U2 1201
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 354
EP 357
DI 10.1038/370354a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400050
DA 2026-03-10
ER

PT J
AU SIEGRIST, T
   ZANDBERGEN, HW
   CAVA, RJ
   KRAJEWSKI, JJ
   PECK, WF
AF SIEGRIST, T
   ZANDBERGEN, HW
   CAVA, RJ
   KRAJEWSKI, JJ
   PECK, WF
TI THE CRYSTAL-STRUCTURE OF SUPERCONDUCTING LUNI2B2C AND THE RELATED PHASE LUNIBC
SO NATURE
LA English
DT Article
AB SUPERCONDUCTING intermetallic compounds with relatively high transition temperature (T(c)) have been found in the systems Ln-Tr-B-C, where Ln is a lanthanide element (Y, Ho-Lu) and Tr a transition metal (Pd or Ni)1,2. In the nickel-bearing system, the superconducting phase has the formula LnNi2B2C (ref. 2). Although many structures are known for ternary carbides and borides, only a few have been reported for quaternary borocarbides3. Here we describe two new.phases that form in the Lu-Ni-B-C system: LuNi2B2C, a superconductor with a T(c) of 16.6 K (ref. 2), and LuNiBC, a closely related non-superconducting phase. The superconductor is a variant on the layered ThCr2Si2-type structure4,  with additional carbon in the Lu plane. LuNiBC is derived from LuNi2B2C by adding another layer of Lu-C, producing a NaCl-type intergrowth. A new homologous series of intermetallic phases may be derivable from the simple building principles of these two structures.
C1 DELFT UNIV TECHNOL,NATL CTR HIGH RESOLUT ELECTRON MICROSCOPY,2628 AL DELFT,NETHERLANDS.
C3 Delft University of Technology
RP SIEGRIST, T (corresponding author), AT&T BELL LABS,600 MT AVE,MURRAY HILL,NJ 07974, USA.
NR 11
TC 506
Z9 516
U1 1
U2 63
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 254
EP 256
DI 10.1038/367254a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400049
DA 2026-03-10
ER

PT J
AU ZAHN, R
   SPITZFADEN, C
   OTTIGER, M
   WUTHRICH, K
   PLUCKTHUN, A
AF ZAHN, R
   SPITZFADEN, C
   OTTIGER, M
   WUTHRICH, K
   PLUCKTHUN, A
TI DESTABILIZATION OF THE COMPLETE PROTEIN SECONDARY STRUCTURE ON BINDING TO THE CHAPERONE GROEL
SO NATURE
LA English
DT Article
ID molecular chaperone; beta-lactamase; cyclophilin; reconstitution; cooperativity; aggregation; polypeptide; invitro; atp; nmr
AB PROTEIN folding in vivo is mediated by helper proteins, the molecular chaperones(1-3), of which Hsp60 and its Escherichia coli variant GroEL are some of the best characterized. GroEL is an oligomeric protein with 14 subunits each of M(r) 60K(4-6), which possesses weak, co-operative ATPase activity(7-9) and high plasticity(10). GroEL seems to interact with non-native proteins, binding one or two molecules per 14-mer(11-19) in a 'central cavity'(20), but little is known about the conformational state of the bound polypeptides. Here we use nuclear magnetic resonance techniques to show that the interaction of the small protein cyclophilin(21,22) with GroEL is reversible by temperature changes, and all amide protons in GroEL-bound cyclophilin are exchanged with the solvent, although this exchange does not occur in free cyclophilin. The complete secondary structure of cyclophilin must be disrupted when bound to GroEL.
C1 MAX PLANCK INST BIOCHEM,PROT ENGN GRP,D-82152 MARTINSRIED,GERMANY.
   ETH HONGGERBERG,INST MOLEK BIOL & BIOPHYS,CH-8093 ZURICH,SWITZERLAND.
C3 Max Planck Society; Swiss Federal Institutes of Technology Domain; ETH Zurich
NR 32
TC 147
Z9 154
U1 0
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 261
EP 265
DI 10.1038/368261a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000061
PM 7908413
DA 2026-03-10
ER

PT J
AU PEREZMORENO, BP
   SANZ, JL
   BUSCALIONI, AD
   MORATALLA, JJ
   ORTEGA, F
   RASSKINGUTMAN, D
AF PEREZMORENO, BP
   SANZ, JL
   BUSCALIONI, AD
   MORATALLA, JJ
   ORTEGA, F
   RASSKINGUTMAN, D
TI A UNIQUE MULTITOOTHED ORNITHOMIMOSAUR DINOSAUR FROM THE LOWER CRETACEOUS OF SPAIN
SO NATURE
LA English
DT Article
ID birds
AB The Lower Cretaceous lithographic limestones from Las Hoyas (province of Cuenca, Spain) have yielded important vertebrate fossil remains. We report here a new specimen, the first ornithomimosaur theropod found in Europe. Pelecanimimus polyodon gen. et sp. nov., has some striking elements preserved, such as the hyoid, sternum and integumentary impressions. The fossil has revealed other unexpected features, including a derived hand in an ancient ornithomimosaur, and a large number of teeth (over 200) with a distinctive morphology. This specimen suggests an alternative evolutionary process towards the toothless condition in Omithomimosauria, which could be explained by an exaptation. Pelecanimimus polyodon stresses the relationship between Troodontidae and Ornithomimosauria.
RP PEREZMORENO, BP (corresponding author), UNIV AUTONOMA MADRID,FAC CIENCIAS,DEPT BIOL,PALEONTOL UNIDAD,E-28049 MADRID,SPAIN.
NR 23
TC 155
Z9 166
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 363
EP 367
DI 10.1038/370363a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400053
DA 2026-03-10
ER

PT J
AU ANDERSON, MW
   TERASAKI, O
   OHSUNA, T
   PHILIPPOU, A
   MACKAY, SP
   FERREIRA, A
   ROCHA, J
   LIDIN, S
AF ANDERSON, MW
   TERASAKI, O
   OHSUNA, T
   PHILIPPOU, A
   MACKAY, SP
   FERREIRA, A
   ROCHA, J
   LIDIN, S
TI STRUCTURE OF THE MICROPOROUS TITANOSILICATE ETS-10
SO NATURE
LA English
DT Article
AB INORGANIC microporous framework solids such as zeolites are of considerable technological importance as shape-selective catalysts, ion-exchange materials and molecular sieves1. Most microporous materials known until recently were silicates, aluminosilicates1 or aluminophosphates2-4, all of which contain tetrahedrally coordinated metal atoms. In 1989, a family of microporous titanosilicates (generically denoted ETS) was discovered in which the metal atoms (Ti4+) are octahedrally coordinated5-8. A full understanding of the potential of any microporous solid to act as a molecular sieve and selective catalyst, and of the nature of the catalytic centres, requires that its structure be known. But that of the ETS materials has proved elusive because of the considerable degree of disorder that they contain. Using a combination of high-resolution electron microscopy, electron and powder X-ray diffraction, solid-state NMR, molecular modelling and chemical analysis, we have now been able to solve the structure of a prominent member of this family, ETS-10. This structure comprises corner-sharing SiO4 tetrahedra and TiO6 octahedra linked through bridging oxygen atoms. The pore system contains 12-membered rings and displays a considerable degree of disorder. Many ordered variants of ETS-10 exist, some of which are chiral.
C1 TOHOKU UNIV,DEPT PHYS,SENDAI,MIYAGI 980,JAPAN.
   IWAKI MEISEI UNIV,COLL SCI & ENGN,IWAKI,FUKUSHIMA 970,JAPAN.
   UNIV AVEIRO,DEPT CHEM,P-3800 AVEIRO,PORTUGAL.
   LUND UNIV,CTR CHEM,S-22101 LUND,SWEDEN.
C3 Tohoku University; Iryo Sosei University; Universidade de Aveiro; Lund University
RP ANDERSON, MW (corresponding author), UNIV MANCHESTER,INST SCI & TECHNOL,DEPT CHEM,POB 88,MANCHESTER M60 1QD,LANCS,ENGLAND.
NR 12
TC 554
Z9 594
U1 3
U2 177
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 27
PY 1994
VL 367
IS 6461
BP 347
EP 351
DI 10.1038/367347a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MT540
UT WOS:A1994MT54000060
DA 2026-03-10
ER

PT J
AU FROLOVA, L
   LEGOFF, X
   RASMUSSEN, HH
   CHEPEREGIN, S
   DRUGEON, G
   KRESS, M
   ARMAN, I
   HAENNI, AL
   CELIS, JE
   PHILIPPE, M
   JUSTESEN, J
   KISSELEV, L
AF FROLOVA, L
   LEGOFF, X
   RASMUSSEN, HH
   CHEPEREGIN, S
   DRUGEON, G
   KRESS, M
   ARMAN, I
   HAENNI, AL
   CELIS, JE
   PHILIPPE, M
   JUSTESEN, J
   KISSELEV, L
TI A HIGHLY CONSERVED EUKARYOTIC PROTEIN FAMILY POSSESSING PROPERTIES OF POLYPEPTIDE-CHAIN RELEASE FACTOR
SO NATURE
LA English
DT Article
ID transfer rna-synthetase; saccharomyces-cerevisiae; translation fidelity; nucleotide-sequence; gene-product; yeast; termination; sup45; homology; cloning
AB THE termination of protein synthesis in ribosomes is governed by termination (stop) codons in messenger RNAs and by polypeptide chain release factors (RFs). Although the primary structure of prokaryotic RFs and yeast mitochrondrial RF is established(1-4), that of the only known eukaryotic RF (eRF)(5) remains obscure. Here we report the assignment of a family of tightly related proteins (designated eRF1) from lower and higher eukaryotes which are structurally and functionally similar to rabbit eRF. Two of these proteins, one from human(6) and the other from Xenopus laevis(7), have been expressed in yeast and Escherichia coli, respectively, purified and shown to be active in the in vitro RF assay. The other protein of this family, sup45 (sup1) of Saccharomyces cerevisiae, is involved in omnipotent suppression during translations(8-12). The amino-acid sequence of the eRF1 family is highly conserved. We conclude that the eRF1 proteins are directly implicated in the termination of translation in eukaryotes.
C1 RUSSIAN ACAD SCI,VA ENGELHARDT MOLEC BIOL INST,MOSCOW 117984,RUSSIA.
   AARHUS UNIV,DEPT BIOL MOLEC,DK-800 AARHUS C,DENMARK.
   INST JACQUES MONOD,F-75251 PARIS 05,FRANCE.
   UNIV RENNES 1,CNRS,URA 256,DEPT BIOL & GENET DEV,F-35042 RENNES,FRANCE.
   AARHUS UNIV,INST MED BIOCHEM,DK-8000 AARHUS C,DENMARK.
   AARHUS UNIV,DANISH CTR HUMAN GENOME RES,DK-8000 AARHUS C,DENMARK.
   RUSSIAN ACAD SCI,INST MOLEC GENET,MOSCOW 123182,RUSSIA.
   CNRS,ERS0048,MOLEC ONCOL LAB,F-94802 VILLEJUIF,FRANCE.
C3 Russian Academy of Sciences; Engelhardt Institute of Molecular Biology, RAS; Aarhus University; Universite Paris Cite; Centre National de la Recherche Scientifique (CNRS); Universite de Rennes; Aarhus University; Aarhus University; Russian Academy of Sciences; Centre National de la Recherche Scientifique (CNRS)
NR 25
TC 365
Z9 420
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 701
EP 703
DI 10.1038/372701a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700093
PM 7990965
DA 2026-03-10
ER

PT J
AU LU, W
   HAN, DS
   YUAN, J
   ANDRIEU, JM
AF LU, W
   HAN, DS
   YUAN, J
   ANDRIEU, JM
TI MULTITARGET PCR ANALYSIS BY CAPILLARY ELECTROPHORESIS AND LASER-INDUCED FLUORESCENCE
SO NATURE
LA English
DT Article
ID polymerase chain-reaction
RP LU, W (corresponding author), UNIV PARIS 05,HOP LAENNEC,TUMOR IMMUNOL LAB,F-75007 PARIS,FRANCE.
NR 15
TC 79
Z9 85
U1 0
U2 14
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 269
EP 271
DI 10.1038/368269a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000063
PM 8145828
DA 2026-03-10
ER

PT J
AU ZHANG, H
   WANG, YY
   ZHANG, H
   DRAVID, VP
   MARKS, LD
   HAN, PD
   PAYNE, DA
   RADAELLI, PG
   JORGENSEN, JD
AF ZHANG, H
   WANG, YY
   ZHANG, H
   DRAVID, VP
   MARKS, LD
   HAN, PD
   PAYNE, DA
   RADAELLI, PG
   JORGENSEN, JD
TI IDENTITY OF PLANAR DEFECTS IN THE INFINITE-LAYER COPPER-OXIDE SUPERCONDUCTOR
SO NATURE
LA English
DT Article
ID high-pressure
AB The 'infinite-layer' compound(1-3) ACuO(2) (where A stands for cations such as strontium or calcium), has the simplest structure of all superconducting copper oxides, with only bare cations separating the CuO2 planes. Accordingly, an understanding of the doping mechanism(s) that lead to superconductivity in this compound may facilitate the elucidation of the same phenomenon in the other copper oxide superconductors. Recently, Azuma and co-workers(2,4) observed planar defects in an infinite-layer phase synthesized at high oxygen pressure, and proposed that the defects are A-cation deficient, and lead to superconductivity (with transition temperature T-c approximate to 100-110 K) in this compound. Here, based on quantitative X-ray and high-resolution electron-microscopic analysis of the planar defects in (Sr, Ca)CuO2, we propose that the defects consist of a corrugated Sr-O layer substituted for a CuO2 layer, with the incorporation of apical oxygen atoms (which are absent in the parent structure) at roughly half the available sites in the neighbouring Sr layers. This is equivalent to an insertion of a Sr3O2+/-x block in an otherwise infinite-layer sequence. The variable oxygen stoichiometry of our defect model can account for the occurrence of p-type superconductivity (following high-pressure oxygenation), n-type superconductivity (high-pressure reduction) or lack of superconductivity (high-pressure neutral-atmosphere annealing) in this system, depending on the synthesis conditions(4).
C1 NORTHWESTERN UNIV,SCI & TECHNOL CTR SUPERCONDUCT,DEPT MAT SCI & ENGN,EVANSTON,IL 60208.
   UNIV ILLINOIS,DEPT MAT SCI & ENGN,URBANA,IL 61801.
   ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439.
C3 Northwestern University; University of Illinois System; University of Illinois Urbana-Champaign; United States Department of Energy (DOE); Argonne National Laboratory
NR 11
TC 39
Z9 43
U1 0
U2 19
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 4
PY 1994
VL 370
IS 6488
BP 352
EP 354
DI 10.1038/370352a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PA304
UT WOS:A1994PA30400049
DA 2026-03-10
ER

PT J
AU MOYLE, WR
   CAMPBELL, RK
   MYERS, RV
   BERNARD, MP
   HAN, Y
   WANG, XY
AF MOYLE, WR
   CAMPBELL, RK
   MYERS, RV
   BERNARD, MP
   HAN, Y
   WANG, XY
TI COEVOLUTION OF LIGAND-RECEPTOR PAIRS
SO NATURE
LA English
DT Article
ID follicle-stimulating-hormone; human chorionic-gonadotropin; glycoprotein hormones; extracellular domain; high-affinity; beta-subunit; choriogonadotropin; chimeras; expression; sequence
AB SPECIFIC receptors for lutropin(1,2) (luteinizing hormone; LH) and follitropin(3,4) (follicle-stimulating hormone; FSH) mediate the actions of human chorionic gonadotropin (hCG) and FSH5 on the gonads. Here we report that short independent sequences of the beta-subunit enable hCG to distinguish between the receptors for FSH and LH. Residues between the 11th and 12th cysteines restrict FSH receptor binding; residues between the 10th and 11th cysteines and, to a much lesser extent, residues carboxy-terminal to the 12th cysteine also affect LH receptor binding. CF101-109, an hCG analogue containing hFSH beta residues between the 11th and 12th cysteines, had high affinity for both LH and FSH receptors. Modifications to CF101-109 that reduce binding to either LH or FSH receptors yield gonadotropin analogues having differing ratios of LH:FSH activity. Ligand-binding specificity of the LH receptor is determined by residues encoded by parts of exons 2-4 and 7-9 which prevent hFSH binding but have little effect on hCG binding. FSH receptor specificity is controlled primarily by residues encoded by exons 5 and 6 that prevent hCG binding but have little effect on hFSH binding. These determinants can be interchanged to create receptor analogues that bind hCG and hFSH. Our observations support a model in which distinct negative determinants restrict ligand-receptor interaction. This explains coevolution of binding specificity in families of homologous ligands and their receptors. Natural or designed manipulation of these determinants leads to the 'evolution' of new, specific protein-protein interactions.
RP MOYLE, WR (corresponding author), UNIV MED & DENT NEW JERSEY,ROBERT WOOD JOHNSON RUTGERS MED SCH,DEPT OBSTET & GYNECOL,PISCATAWAY,NJ 08854, USA.
NR 24
TC 317
Z9 354
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 17
PY 1994
VL 368
IS 6468
BP 251
EP 255
DI 10.1038/368251a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA870
UT WOS:A1994NA87000058
PM 8145825
DA 2026-03-10
ER

PT J
AU KIM, TK
   HASHIMOTO, S
   KELLEHER, RJ
   FLANAGAN, PM
   KORNBERG, RD
   HORIKOSHI, M
   ROEDER, RG
AF KIM, TK
   HASHIMOTO, S
   KELLEHER, RJ
   FLANAGAN, PM
   KORNBERG, RD
   HORIKOSHI, M
   ROEDER, RG
TI EFFECTS OF ACTIVATION-DEFECTIVE TBP MUTATIONS ON TRANSCRIPTION INITIATION IN YEAST
SO NATURE
LA English
DT Article
ID polymerase-ii transcription; preinitiation complex; binding-protein; basic repeat; dna-binding; invitro; vp16
AB TRANSCRIPTION initiation by RNA polymerase II is effected by an ordered series of general factor interactions with core promoter elements (leading to basal activity) and further regulated by gene-specific factors acting from distal elements(1). Both the general factor TFIID (refs 2,3), including the constituent TBP (TATA-binding polypeptide)(4-7) and associated factors(8), and the interacting factor TFIIB (refs 9-11) have been implicated as targets for various activators. Towards an understanding of the basis for activator function, including the multiplicity of TBP interactions, we have now identified mutations in yeast TBP that selectively block activator (GAL4-VP16)-dependent but not basal transcription. We further show an effect of GAL4-VP16 on TFIIB recruitment to early preinitiation complexes, and that recruitment is disrupted by TBP mutations that impair its interactions with VP16 (L114K), TFIIB (L189K) or an unidentified component (K211L). Thus, GAL4-VP16 function seems to involve both direct interactions with TBP and a corresponding induction (or stabilization) of an activation-specific TBP-TFIIb-promoter complex.
C1 STANFORD UNIV, SCH MED, DEPT CELL BIOL, STANFORD, CA 94305 USA.
C3 Stanford University
RP KIM, TK (corresponding author), ROCKEFELLER UNIV, BIOCHEM & MOLEC BIOL LAB, NEW YORK, NY 10021 USA.
NR 30
TC 111
Z9 118
U1 1
U2 3
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 252
EP 255
DI 10.1038/369252a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700062
PM 8183347
DA 2026-03-10
ER

PT J
AU CHUNG, JK
   GRAMMER, TC
   LEMON, KP
   KAZLAUSKAS, A
   BLENIS, J
AF CHUNG, JK
   GRAMMER, TC
   LEMON, KP
   KAZLAUSKAS, A
   BLENIS, J
TI PDGF-DEPENDENT AND INSULIN-DEPENDENT PP70(S6K) ACTIVATION MEDIATED BY PHOSPHATIDYLINOSITOL-3-OH KINASE
SO NATURE
LA English
DT Article
ID growth-factor receptor; s6 protein-kinase; signal-transduction; phosphorylation; 3-kinase; inhibition; p70(s6k); 3,4,5-trisphosphate; expression; wortmannin
AB PLATELET-DERIVED growth factor receptor (PDGF-R) phosphorylation at tyrosines 740/751 and insulin receptor phosphorylation of insulin receptor substrate-1 effects the recruitment and activation of phosphatidylinositol-3-OH kinase (PI(3)K)(1-5). Changes in PI(3)K activity correlate with cell growth but its downstream signal transducers are unknown(4,5). Activation of the 70/85K S6 kinases (pp70(S6k)) by serine phosphorylation(6,7) results in 40S ribosomal protein S6 phosphorylation and is important for G1 cell-cycle transition in a variety of cells(8-11). Although receptor tyrosine kinases activate the microtubule-associated protein kinase cascade through SH2-/SH3-adaptor proteins, Sos and c-Ras(12), it is unclear how tyrosine kinases are coupled to the pp70(S6k) phosphorylation cascade. Here we report that PI(3)K mediates PDGF or insulin receptor signalling to pp70(S6k). PI(3)K-mediated activation of pp70(S6k) is independent of conventional protein kinase C isoforms. Additionally, rapamycin blocks pp70(S6k) activation by all mitogens(8-10), without inhibiting PI(3)M, and acts downstream this signalling system.
C1 HARVARD UNIV,SCH MED,DEPT CELL BIOL,BOSTON,MA 02115.
   NATL JEWISH CTR IMMUNOL & RESP MED,DENVER,CO 80206.
C3 Harvard University; Harvard Medical School; National Jewish Health
NR 30
TC 693
Z9 746
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 71
EP 75
DI 10.1038/370071a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100062
PM 8015612
DA 2026-03-10
ER

PT J
AU KLEIN, J
   KUMACHEVA, E
   MAHALU, D
   PERAHIA, D
   FETTERS, LJ
AF KLEIN, J
   KUMACHEVA, E
   MAHALU, D
   PERAHIA, D
   FETTERS, LJ
TI REDUCTION OF FRICTIONAL FORCES BETWEEN SOLID-SURFACES BEARING POLYMER BRUSHES
SO NATURE
LA English
DT Article
ID shear
AB THE use of lubricants to reduce friction and wear between rubbing surfaces has been documented since antiquity(1-3). Recent approaches have focused on boundary lubrication by surfactantlike species coating the surfaces, whereby the friction between them is replaced by the weaker forces required for shear of adhesive contacts between the surfactant layers(3,4). An alternative approach is to tether polymer chains to the surfaces by one end which, when swollen by a solvent, then act as molecular 'brushes' that may facilitate sliding. The normal forces between sliding brush-bearing surfaces have been previously investigated(5,6), but the lateral forces, which are the most important from the point of view of lubrication, are harder to measure. Here we report the measurement of lateral forces in such a system. We find a striking reduction in the effective friction coefficients mu(b) between the surfaces to below our detection limit (mu(b) < 0.001), for contact pressures of around 1 MPa and sliding velocities from zero to 450 nm s(-1). We believe that this effect is due to the long-ranged repulsion, of entropic origin, between the brushes, which acts to keep the surfaces apart while maintaining a relatively fluid layer at the interface between them.
C1 EXXON RES & ENGN CO,ANNANDALE,NJ 08801.
C3 Exxon Mobil Corporation
RP KLEIN, J (corresponding author), WEIZMANN INST SCI,DEPT MAT & INTERFACES,IL-76100 REHOVOT,ISRAEL.
NR 23
TC 556
Z9 622
U1 4
U2 296
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 634
EP 636
DI 10.1038/370634a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000044
DA 2026-03-10
ER

PT J
AU HARADA, Y
   YAMAMOTO, S
   AOKI, M
   MASUDA, S
   ICHINOKAWA, T
   KATO, M
   SAKAI, Y
AF HARADA, Y
   YAMAMOTO, S
   AOKI, M
   MASUDA, S
   ICHINOKAWA, T
   KATO, M
   SAKAI, Y
TI SURFACE SPECTROSCOPY WITH HIGH-SPATIAL-RESOLUTION USING METASTABLE ATOMS
SO NATURE
LA English
DT Article
ID ionization electron-spectroscopy; photoelectron valence band; phthalocyanine compounds; beam source
AB THE study of surface phenomena is in large part dependent on spectroscopic techniques that are sensitive to of only the outermost few layers of the material under consideration. A variety of such techniques are now available, some of which also have the benefit of high spatial resolution(1-3) Here we show that metastable atoms-that is, atoms in long-lived excited states-can be used as a sensitive surface probe with high spatial resolution. In contrast to electrons or photons, metastable atoms cannot penetrate into a solid; instead, they are de-excited readily following interaction with the surface electronic orbitals(4,5). The de-excitation process is accompanied by the emission of electrons, the energy spectrum of which provides fundamental information about the electronic properties of the surface. High spatial resolution (in the present case, about 5 mu m) is achieved by detecting electrons that have been emitted from only a small area of the sample. As the metastable atoms have only thermal kinetic energies, they are essentially nondestructive, making them ideally suited to probing fragile surfaces such as organic layers and biological specimens.
C1 UNIV TOKYO,COLL ARTS & SCI,DEPT CHEM,MEGURO KU,TOKYO 153,JAPAN.
   WASEDA UNIV,DEPT APPL PHYS,SHINJUKU KU,TOKYO 160,JAPAN.
   JEOL LTD,AKISHIMA,TOKYO 196,JAPAN.
C3 University of Tokyo; Waseda University; Jeol Ltd
RP HARADA, Y (corresponding author), CHIBA UNIV,FAC ENGN,DEPT MAT SCI,INAGE KU,YAYOI CHO,CHIBA 263,JAPAN.
NR 18
TC 32
Z9 32
U1 0
U2 11
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 657
EP 659
DI 10.1038/372657a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700080
DA 2026-03-10
ER

PT J
AU GERSHON, D
AF GERSHON, D
TI CHANGING TIMES FOR NEUROSCIENTISTS
SO NATURE
LA English
DT Article
AB At a time of considerable uncertainty for the biotechnology industry, Nature reviews the prospects for neuroscientists considering a move out of the academic sector.
NR 0
TC 0
Z9 0
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 203
EP 204
DI 10.1038/372203a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800064
PM 7969454
DA 2026-03-10
ER

PT J
AU WILLIAMS, RW
   HOGAN, D
   GARRAGHTY, PE
AF WILLIAMS, RW
   HOGAN, D
   GARRAGHTY, PE
TI TARGET RECOGNITION AND VISUAL MAPS IN THE THALAMUS OF ACHIASMATIC DOGS
SO NATURE
LA English
DT Article
ID lateral geniculate-nucleus; binocular competition; siamese cat; projections; organization; pathways; field
AB VISION is dependent on ordered neuronal representations or maps of visual space. These maps depend on precise connections between retinal axons and their targets cells. In mammals, nerve fibres from right and left eyes produce congruent maps of contralateral visual space in adjacent layers of the lateral geniculate nucleus (LGN)(1). We have identified an autosomal recessive mutation in Belgian sheepdogs(2,3) that eliminates the optic chiasm. In these mutants, all retinal axons project into the ipsilateral optic tract, including those originating in the nasal hemiretina that normally cross midline. These animals exhibit a pronounced horizontal nystagmus(4,5). The abnormal ipsilaterally directed nasal fibres innervate the LGN as if they had successfully crossed the midline, terminating in the appropriate layer of the nucleus. As a consequence, the LGN contains non-congruent, mirror-image maps of visual space in adjacent layers. These results show that there is a robust affinity between nasal and temporal retinal axons and,specific LGN layers even when all retinal axons originate from a single eye.
C1 INDIANA UNIV, DEPT PSYCHOL, PROGRAM NEURAL SCI, BLOOMINGTON, IN 47405 USA.
C3 Indiana University System; Indiana University Bloomington
RP WILLIAMS, RW (corresponding author), UNIV TENNESSEE, SCH MED, DEPT ANAT & NEUROBIOL, 855 MONROE AVE, MEMPHIS, TN 38163 USA.
NR 24
TC 69
Z9 76
U1 0
U2 5
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD FEB 17
PY 1994
VL 367
IS 6464
BP 637
EP 639
DI 10.1038/367637a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MW688
UT WOS:A1994MW68800051
PM 8107846
DA 2026-03-10
ER

PT J
AU LEW, J
   HUANG, QQ
   QI, Z
   WINKFEIN, RJ
   AEBERSOLD, R
   HUNT, T
   WANG, JH
AF LEW, J
   HUANG, QQ
   QI, Z
   WINKFEIN, RJ
   AEBERSOLD, R
   HUNT, T
   WANG, JH
TI A BRAIN-SPECIFIC ACTIVATOR OF CYCLIN-DEPENDENT KINASE-5
SO NATURE
LA English
DT Article
ID directed protein-kinase; tau-protein; phosphorylation; sequence; identification; neurofilaments; cdc2; p34(cdc2); subunit; sites
AB PHOSPHORYLATION of the neurofilament proteins of high and medium relative molecular mass, as well as of the Alzheimer's tau protein, is thought to be catalysed by a protein kinase with Cdc2-like substrate specificity(1-7). We have purified a novel Cdc2-like kinase from bovine brain(8) capable of phosphorylating both the neurofilament proteins(9) and tau(10). The purified enzyme is a heterodimer of cyclin-dependent kinase 5 (Cdk5)(9) and a novel regulatory subunit, p25 (ref. 8). When overexpressed and purified from Escherichia coli, p25 can activate Cdk5 in vitro. Unlike Cdk5, which is ubiquitously expressed in human tissue, the p25 transcript is expressed only in brain. A full-length complementary DNA clone showed that p25 is a truncated form of a larger protein precursor, p35, which seems to be the predominant form of the protein in crude brain extract. Cdk5/p35 is the first example of a Cdc2-like kinase with neuronal function.
C1 UNIV CALGARY,MRC,SIGNAL TRANSDUCT GRP,CALGARY T2N 4N1,AB,CANADA.
   UNIV BRITISH COLUMBIA,BIOMED RES CTR,VANCOUVER,BC,CANADA.
   UNIV BRITISH COLUMBIA,DEPT BIOCHEM & MOLEC BIOL,VANCOUVER,BC,CANADA.
   IMPERIAL CANC RES FUND,CLARE HALL LABS,S MIMMS EN6 3LD,HERTS,ENGLAND.
C3 University of Calgary; University of British Columbia; University of British Columbia
NR 25
TC 557
Z9 626
U1 0
U2 8
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 29
PY 1994
VL 371
IS 6496
BP 423
EP 426
DI 10.1038/371423a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PJ285
UT WOS:A1994PJ28500044
PM 8090222
DA 2026-03-10
ER

PT J
AU KOPF, M
   BAUMANN, H
   FREER, G
   FREUDENBERG, M
   LAMERS, M
   KISHIMOTO, T
   ZINKERNAGEL, R
   BLUETHMANN, H
   KOHLER, G
AF KOPF, M
   BAUMANN, H
   FREER, G
   FREUDENBERG, M
   LAMERS, M
   KISHIMOTO, T
   ZINKERNAGEL, R
   BLUETHMANN, H
   KOHLER, G
TI IMPAIRED IMMUNE AND ACUTE-PHASE RESPONSES IN INTERLEUKIN-6-DEFICIENT MICE
SO NATURE
LA English
DT Article
ID vaccinia virus; growth-factor; cytokines; receptor; cd8+
AB INTERLEUKIN-6 (IL-6) is a multifunctional cytokine that regulates various aspects of the immune response, acute-phase reaction and haematopoiesis (for reviews see refs 1, 2). In vitro, leukaemia inhibitory factor, oncostatin M, ciliary neurotrophic factor and interleukin-ll display overlapping activities with IL-6. This functional redundancy may be explained by the interactions of specific binding receptors with a common signal-transducing receptor (gp130) (for reviews see refs 3, 4). To elucidate the unique function of IL-6 in vivo, we have disrupted the IL-6 gene by homologous recombination. IL-6-deficient mice develop normally. They fail to control efficiently vaccinia virus and infection with Listeria mono-cytogenes, a facultative intracellular bacterium. The T-cell-dependent antibody response against vesicular stomatitis virus is impaired. Further, the inflammatory acute-phase response after tissue damage or infection is severely compromised, whereas it is only moderately affected after challenge with lipopolysaccharide. We conclude that IL-6 production induced by injury or infection is an important in vivo SOS signal which coordinates activities of liver cells, macrophages and lymphocytes.
C1 ROSWELL PK CANC INST, DEPT MOLEC & CELLULAR BIOL, BUFFALO, NY 14263 USA.
   UNIV ZURICH, INST EXPTL IMMUNOL, ZURICH, SWITZERLAND.
   HOFFMANN LA ROCHE AG, DEPT BIOL, CH-4002 BASEL, SWITZERLAND.
   OSAKA UNIV, SCH MED, DEPT MED 3, OSAKA, OSAKA 565, JAPAN.
C3 Roswell Park Comprehensive Cancer Center; University of Zurich; Roche Holding; University of Osaka
RP KOPF, M (corresponding author), MAX PLANCK INST IMMUNBIOL, STUBEWEG 51, D-79108 FREIBURG, GERMANY.
NR 30
TC 1585
Z9 1778
U1 1
U2 67
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD MAR 24
PY 1994
VL 368
IS 6469
BP 339
EP 342
DI 10.1038/368339a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NB985
UT WOS:A1994NB98500047
PM 8127368
DA 2026-03-10
ER

PT J
AU LOVELOCK, JE
   KUMP, LR
AF LOVELOCK, JE
   KUMP, LR
TI FAILURE OF CLIMATE REGULATION IN A GEOPHYSIOLOGICAL MODEL
SO NATURE
LA English
DT Article
ID vostok ice core; atmospheric co2; north-atlantic; cloud albedo; cycle; sulfur; phytoplankton; aerosol
AB THERE has been much debate about how the Earth responds to changes in climate-specifically, how feedbacks involving the biota change with temperature. There is in particular an urgent need to understand the extent of coupling and feedback between plant growth, global temperature and enhanced atmospheric concentrations of greenhouse gases. Here we present a simple, but we hope qualitatively realistic, analysis of the effects of temperature change on the feedbacks induced by changes in surface distribution of marine algae and land plants. We assume that algae affect climate primarily through their emission of dimethyl sulphide(1-8) (which may influence cloud albedo), and that land plants do so by fixation of atmospheric CO2 (refs 9-12). When we consider how the planetary area occupied by these two ecosystems varies with temperature, we find that a simple model based on these ideas exhibits three feedback regimes. In glacial conditions, both marine and terrestrial ecosystems provide a negative feedback. As the temperature rises to present-day values, algae lose their strong climate influence, but terrestrial ecosystems continue to regulate the climate. But if global mean temperatures rise above about 20 degrees C, both terrestrial and marine ecosystems are in positive feedback, amplifying any further increase of temperature. As the latter conditions have existed in the past, we propose that other climate-regulating mechanisms must operate in this warm regime.
C1 PENN STATE UNIV, CTR EARTH SYST SCI, University Pk, PA 16802 USA.
   PENN STATE UNIV, DEPT GEOSCI, University Pk, PA 16802 USA.
C3 Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
NR 36
TC 49
Z9 55
U1 0
U2 25
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 732
EP 734
DI 10.1038/369732a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100055
DA 2026-03-10
ER

PT J
AU BEZRUKOV, SM
   VODYANOY, I
   PARSEGIAN, VA
AF BEZRUKOV, SM
   VODYANOY, I
   PARSEGIAN, VA
TI COUNTING POLYMERS MOVING THROUGH A SINGLE-ION CHANNEL
SO NATURE
LA English
DT Article
ID probing alamethicin channels; water-soluble polymers; membranes; model
AB THE change in conductance of a small electrolyte-filled capillary owing to the passage of sub-micrometre-sized particles has long been used for particle counting and sizing. A commercial device for such measurements, the Coulter counter, is able to detect particles of sizes down to several tenths of a micrometre(1-3). Nuclepore technology (in which pores are etched particle tracks) has extended the lower limit of size detection to 60-nm particles by using a capillary of diameter 0.45 mu m (ref. 4). Here we show that natural channel-forming peptides incorporated into a bilayer lipid membrane can be used to detect the passage of single molecules with gyration radii as small as 5-15 Angstrom. From our experiments with alamethicin pores we infer both the average number and the diffusion coefficients of poly(ethylene glycol) molecules in the pore. Our approach provides a means of observing the statistics and mechanics of flexible polymers moving within the confines of precisely defined single-molecule structures.
C1 NIH,DCRT,STRUCT BIOL LAB,BETHESDA,MD 20892.
   RUSSIAN ACAD SCI,INST NUCL PHYS,ST PETERSBURG 188350,RUSSIA.
   OFF NAVAL RES,ARLINGTON,VA 22217.
C3 National Institutes of Health (NIH) - USA; Russian Academy of Sciences; National Research Centre - Kurchatov Institute; Institute of High Energy Physics - IHEP; United States Department of Defense; United States Navy; Office of Naval Research
RP BEZRUKOV, SM (corresponding author), NIDDK,DIV INTRAMURAL RES,BETHESDA,MD 20892, USA.
NR 20
TC 355
Z9 463
U1 0
U2 76
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 28
PY 1994
VL 370
IS 6487
BP 279
EP 281
DI 10.1038/370279a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NZ229
UT WOS:A1994NZ22900058
PM 7518571
DA 2026-03-10
ER

PT J
AU WOLFE, GR
   CUNNINGHAM, FX
   DURNFORD, D
   GREEN, BR
   GANTT, E
AF WOLFE, GR
   CUNNINGHAM, FX
   DURNFORD, D
   GREEN, BR
   GANTT, E
TI EVIDENCE FOR A COMMON ORIGIN OF CHLOROPLASTS WITH LIGHT-HARVESTING COMPLEXES OF DIFFERENT PIGMENTATION
SO NATURE
LA English
DT Article
ID chlorophyll-protein complexes; photosystem-i; binding-proteins; red alga; porphyridium-cruentum; higher-plants; green-algae; polypeptides; phycobilism; membranes
AB THE red algae (Rhodophyta), which like cyanobacteria have only chlorophyll a and use phycobilisomes for light-harvesting1,2, are often considered to have originated independently of other photosynthetic eukaryotes, namely the chlorophyll a/b-containing Chlorophyta and the chlorophyll a/c-containing Chromophyta3. Here we report that the red alga Porphyridium cruentum has a chlorophyll a-containing antenna complex functionally associated with photosystem I, and that polypeptides of this antenna complex are immunologically related to those of higher-plant chlorophyll a/h complexes and to those of chromophyte fucoxanthin-chlorophyll a/c antenna complexes. This establishes a clear link between organisms containing phycobilisomes and those containing chlorophyll-based light-harvesting complexes and shows that these antennae can co-exist in the same organism. Furthermore, it suggests that the light-harvesting proteins of all photosynthetic eukaryotes had a common origin and supports the idea that chloroplasts had a common ancestor4-6.
C1 UNIV BRITISH COLUMBIA,DEPT BOT,VANCOUVER V6T 1Z4,BC,CANADA.
C3 University of British Columbia
RP WOLFE, GR (corresponding author), UNIV MARYLAND,DEPT BOT,COLL PK,MD 20742, USA.
NR 26
TC 148
Z9 168
U1 0
U2 18
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 566
EP 568
DI 10.1038/367566a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300061
DA 2026-03-10
ER

PT J
AU KNAPEN, JWJ
   VANDERMADE, AW
   DEWILDE, JC
   VANLEEUWEN, PWNM
   WIJKENS, P
   GROVE, DM
   VANKOTEN, G
AF KNAPEN, JWJ
   VANDERMADE, AW
   DEWILDE, JC
   VANLEEUWEN, PWNM
   WIJKENS, P
   GROVE, DM
   VANKOTEN, G
TI HOMOGENEOUS CATALYSTS BASED ON SILANE DENDRIMERS FUNCTIONALIZED WITH ARYLNICKEL(II) COMPLEXES
SO NATURE
LA English
DT Article
ID organonickel(ii) complexes; polyhalogenoalkanes; arborols; olefins
AB AT the interface between heterogeneous and homogeneous catalysis there is great scope for the development of new materials that combine the advantages and/or minimize disadvantages associated with each of these classes. In particular there is a need for homogeneous catalysts with properties that allow their ready removal from a product-containing solution. One approach to such materials is to anchor homogeneous catalysts to soluble polymer supports(1); we have recently prepared such catalytic materials in which the active centre is an organometallic species(2,3). One disadvantage encountered when anchoring catalytic metal Sites to polymers is the difficulty of accurate control of the number and location of these sites. Here we report an alternative approach-the synthesis of polysilane dendrimers (highly branched macromolecules(4-6)),which are functionalized at their periphery with metal-containing catalytically active sites. These dendrimers show regiospecific catalytic activity for the Kharasch addition of polyhalogenoalkanes to carbon-carbon double bonds. It should be possible to remove the nanoscale catalytic macromolecules of this type from the solution of products using filtration methods.
C1 UNIV UTRECHT,DEBYE INST,DEPT MET MEDIATED SYNTH,3584 CH UTRECHT,NETHERLANDS.
   AMSTERDAM SHELL RES BV,KONINKLIJKE SHELL LAB,1030 BN AMSTERDAM,NETHERLANDS.
C3 Utrecht University; Royal Dutch Shell
NR 20
TC 736
Z9 772
U1 0
U2 83
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD DEC 15
PY 1994
VL 372
IS 6507
BP 659
EP 663
DI 10.1038/372659a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PX307
UT WOS:A1994PX30700081
DA 2026-03-10
ER

PT J
AU BRAKE, AJ
   WAGENBACH, MJ
   JULIUS, D
AF BRAKE, AJ
   WAGENBACH, MJ
   JULIUS, D
TI NEW STRUCTURAL MOTIF FOR LIGAND-GATED ION CHANNELS DEFINED BY AN IONOTROPIC ATP RECEPTOR
SO NATURE
LA English
DT Article
ID pheochromocytoma cells; functional expression; mammalian neurons; potassium channel; nervous-system; smooth-muscle; pc12 cells; currents; conductance; calcium
AB THE adenosine-5'-triphosphate (ATP) molecule is an extracellular messenger in neural and non-neural tissues, where it activates several cell-surface-receptor subtypes, including G-protein-coupled receptors and ligand-gated ion channels(1). ATP-gated channels (termed P-2X receptors) have been characterized on smooth muscle cells and autonomic and sensory neurons, where they mediate membrane depolarization and, in some cases, Ca2+ entry(2). P-2X receptors are functionally heterogeneous, but resemble acetylcholine- and serotonin-gated channels with respect to ion selectivity and kinetic parameters of channel gating. We report here that despite such close functional similarities, the deduced sequence of a cloned P-2X receptor predicts an unusual subunit structure resembling voltage-insensitive cation channels. Thus, the P-2X receptor provides a striking example of convergent evolution, whereby proteins have been fashioned with similar functional properties from subunits having very different structural characteristics. There is sequence similarity between the ATP receptor and RP-2, a gene activated in thymocytes undergoing programmed cell. death(3). RP-2 may encode a receptor for ATP or another metabolite released during apoptosis.
C1 UNIV CALIF SAN FRANCISCO,SILVIO CONTE CTR NEUROSCI RES,CELL BIOL PROGRAM & NEUROSCI,SAN FRANCISCO,CA 94143.
C3 University of California System; University of California San Francisco
RP BRAKE, AJ (corresponding author), UNIV CALIF SAN FRANCISCO,DEPT PHARMACOL,SAN FRANCISCO,CA 94143, USA.
NR 29
TC 858
Z9 934
U1 0
U2 30
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 519
EP 523
DI 10.1038/371519a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900057
PM 7523952
DA 2026-03-10
ER

PT J
AU LI, CM
   TROPAK, MB
   GERLAI, R
   CLAPOFF, S
   ABRAMOWNEWERLY, W
   TRAPP, B
   PETERSON, A
   RODER, J
AF LI, CM
   TROPAK, MB
   GERLAI, R
   CLAPOFF, S
   ABRAMOWNEWERLY, W
   TRAPP, B
   PETERSON, A
   RODER, J
TI MYELINATION IN THE ABSENCE OF MYELIN-ASSOCIATED GLYCOPROTEIN
SO NATURE
LA English
DT Article
ID cell-adhesion molecules; embryonic stem-cells; schwann-cells; periaxonal space; mice; gene; mag; l1
AB THE hypothesis that myelin-associated glycoprotein (MAG) initiates myelin formation is based in part on observations that MAG has an adhesive role in interactions between oligodendrocytes and neurons(1). Furthermore, the over- or underexpression of MAG in transfected Schwann cells in vitro leads to accelerated myelination(2) or hypomyelination(3), respectively. Here we test this idea by creating a null mutation in the mag locus and deriving mice that are totally deficient in MAG expression at the RNA and protein level. In adult mutant animals the degree of myelination and its compaction are normal, whereas the organization of the periaxonal region is partially impaired. Mutant animals show a subtle intention tremor. Our findings do not support the widely held view that MAG is critical for myelin formation but rather indicate that MAG is necessary for maintenance of the cytoplasmic collar and periaxonal space of myelinated fibres.
C1 UNIV TORONTO, DEPT MOLEC & MED GENET, TORONTO M5G 1X5, ON, CANADA.
   CLEVELAND CLIN FDN, DEPT NEUROSCI, CLEVELAND, OH 44195 USA.
   MCGILL UNIV, ROYAL VICTORIA HOSP, MONTREAL H3A 1A1, PQ, CANADA.
C3 University of Toronto; Cleveland Clinic Foundation; Royal Victoria Hospital; McGill University
RP LI, CM (corresponding author), MT SINAI HOSP, SAMUEL LUNENFELD RES INST, 600 UNIV AVE, TORONTO M5G 1X5, ON, CANADA.
NR 27
TC 323
Z9 371
U1 0
U2 2
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD JUN 30
PY 1994
VL 369
IS 6483
BP 747
EP 750
DI 10.1038/369747a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NU581
UT WOS:A1994NU58100061
PM 7516497
DA 2026-03-10
ER

PT J
AU KYUMA, K
   LANGE, E
   OHTA, J
   HERMANNS, A
   BANISH, B
   OITA, M
AF KYUMA, K
   LANGE, E
   OHTA, J
   HERMANNS, A
   BANISH, B
   OITA, M
TI ARTIFICIAL RETINAS - FAST, VERSATILE IMAGE-PROCESSORS
SO NATURE
LA English
DT Article
ID neural networks; memory
AB Artificial retinas combine video camera and image processing functions, allowing machines to function in their environment with unprecedented autonomy, or to augment quality control, surveillance and hazard monitoring. We review several retina devices and reveal how they execute basic manipulations of the image at processing speeds well beyond the capabilities of the human eye.
RP KYUMA, K (corresponding author), MITSUBISHI ELECTR CORP,SEMICOND RES LAB,8-1-1 TSUKAGUCHI,AMAGASAKI,HYOGO 661,JAPAN.
NR 12
TC 76
Z9 84
U1 0
U2 34
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 10
PY 1994
VL 372
IS 6502
BP 197
EP 198
DI 10.1038/372197a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PQ688
UT WOS:A1994PQ68800062
DA 2026-03-10
ER

PT J
AU CONQUET, F
   BASHIR, ZI
   DAVIES, CH
   DANIEL, H
   FERRAGUTI, F
   BORDI, F
   FRANZBACON, K
   REGGIANI, A
   MATARESE, V
   CONDE, F
   COLLINGRIDGE, GL
   CREPEL, F
AF CONQUET, F
   BASHIR, ZI
   DAVIES, CH
   DANIEL, H
   FERRAGUTI, F
   BORDI, F
   FRANZBACON, K
   REGGIANI, A
   MATARESE, V
   CONDE, F
   COLLINGRIDGE, GL
   CREPEL, F
TI MOTOR DEFICIT AND IMPAIRMENT OF SYNAPTIC PLASTICITY IN MICE LACKING MGLUR1
SO NATURE
LA English
DT Article
ID metabotropic glutamate-receptor; cerebellar purkinje-cells; long-term potentiation; rat-brain; invitro; mouse; hippocampus; expression; induction; activation
AB Metabotropic glutamate receptor 1 (mGluR1) is a member of a large family of G-protein-coupled glutamate receptors, the physiological functions of which are largely unknown. Mice deficient in mGluR1 have severe motor coordination and spatial learning deficits. They have no gross anatomical or basic electrophysiological abnormalities in either the cerebellum or hippocampus, but they show impaired cerebellar long-term depression and hippocampal messy fibre long-term potentiation, mGluR1-deficient mice should therefore be valuable models for studying synaptic plasticity.
C1 GLAXO SPA,GLAXO RES LABS,DEPT PHARMACOL,I-37100 VERONA,ITALY.
   UNIV PARIS 11,F-91405 ORSAY,FRANCE.
   CNRS,DEPT NEUROBIOL,F-91405 ORSAY,FRANCE.
   UNIV BIRMINGHAM,DEPT PHARMACOL,BIRMINGHAM B15 2TT,W MIDLANDS,ENGLAND.
C3 GlaxoSmithKline; GlaxoSmithKline Italy; Universite Paris Saclay; Centre National de la Recherche Scientifique (CNRS); University of Birmingham
RP CONQUET, F (corresponding author), GLAXO INST MOLEC BIOL SA,CH-1228 PLAN LES OUATES,SWITZERLAND.
NR 39
TC 657
Z9 709
U1 0
U2 17
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD NOV 17
PY 1994
VL 372
IS 6503
BP 237
EP 243
DI 10.1038/372237a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PR889
UT WOS:A1994PR88900041
PM 7969468
DA 2026-03-10
ER

PT J
AU DAHLGREN, RA
AF DAHLGREN, RA
TI SOIL ACIDIFICATION AND NITROGEN SATURATION FROM WEATHERING OF AMMONIUM-BEARING ROCK
SO NATURE
LA English
DT Article
ID aluminum; fractionation; nitrification; maturation; toxicity; illite; usa
AB THE Origin of small regions of extremely acidic (pH<4.5) soils in the Klamath mountains of northern California has long been a mystery. These acidic regions are devoid of coniferous vegetation, although surrounded by healthy coniferous forest. Here we show that the extreme soil acidification is caused by nitrogen inputs from ammonium-containing bedrock. Analyses of soil solution composition and bedrock mineralogy reveal that oxidation of ammonium released from the mica schist bedrock generates high levels of nitric acid. The consequent acidity mobilizes potentially toxic levels of aluminium and causes intense leaching of nutrient cations. In the adjacent healthy forest, plant uptake of nitrate attenuates these effects. We suggest that a natural perturbation (for example a small forest fire) caused initial loss of vegetation from the barren regions. We also suggest that subsequent erosion led to serious nutrient depletion of these soils, and that extreme acidification, potentially toxic levels of aqueous aluminium and nutrient deficiencies resulting from cation leaching played a significant role in preventing regrowth. These results show that geological nitrogen, commonly overlooked in biogeochemical cycling but known to be present in appreciable quantities in certain rocks(1-8), may represent a large and reactive pool which can have significant ecological effects.
RP DAHLGREN, RA (corresponding author), UNIV CALIF DAVIS,DEPT LAND AIR & WATER RESOURCES,DAVIS,CA 95616, USA.
NR 26
TC 74
Z9 90
U1 3
U2 64
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 28
PY 1994
VL 368
IS 6474
BP 838
EP 841
DI 10.1038/368838a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NH717
UT WOS:A1994NH71700066
DA 2026-03-10
ER

PT J
AU HASHIMOTO, N
   WATANABE, N
   FURUTA, Y
   TAMEMOTO, H
   SAGATA, N
   YOKOYAMA, M
   OKAZAKI, K
   NAGAYOSHI, M
   TAKEDA, N
   IKAWA, Y
   AIZAWA, S
AF HASHIMOTO, N
   WATANABE, N
   FURUTA, Y
   TAMEMOTO, H
   SAGATA, N
   YOKOYAMA, M
   OKAZAKI, K
   NAGAYOSHI, M
   TAKEDA, N
   IKAWA, Y
   AIZAWA, S
TI PARTHENOGENETIC ACTIVATION OF OOCYTES IN C-MOS-DEFICIENT MICE
SO NATURE
LA English
DT Article
ID proto-oncogene product; meiotic maturation; xenopus oocytes; mouse-tissue; meiosis-ii; eggs; protooncogene; transcripts; expression; features
AB IN Xenopus the c-mos proto-oncogene product (Mos) is essential for the initiation of oocyte maturation(1), for the progression from meiosis I to meiosis II2,3 and for the second meiotic metaphase arrest, acting as an essential component of the cytostatic factor CSF4,5. Its function in mouse oocytes is unclear(6-9), however, as is the biological significance of c-mos mRNA expression in testes(1,10) and several somatic tissues(1,10,11). We have generated c-mos-deficient mice by gene targeting in embryonic stem cells. These mice grew at the same rate as their wild-type counterparts and reproduction was normal in the males, but the fertility of the females was very low. The c-mos-deficient female mice developed ovarian teratomas at a high frequency. Oocytes from these females matured to the second meiotic metaphase both in vivo and in vitro, but were activated without fertilization. The results indicate that in mice Mos plays a role in the second meiotic metaphase arrest, but does not seem to be essential for the initiation of oocyte maturation, spermatogenesis or somatic cell cycle.
C1 MITSUBISHI KASEI INST LIFE SCI,11 MINAMIOOYA,MACHIDA,TOKYO 194,JAPAN.
   INST PHYS & CHEM RES,TSUKUBA LIFE SCI CTR,TSUKUBA,IBARAKI 305,JAPAN.
   KURUME UNIV,INST LIFE SCI,DIV MOLEC GENET,KURUME,FUKUOKA 830,JAPAN.
   TOKYO MED & DENT UNIV,SCH MED,DEPT BIOCHEM,TOKYO 113,JAPAN.
C3 RIKEN; Kurume University; Institute of Science Tokyo; Tokyo Medical & Dental University (TMDU)
NR 24
TC 402
Z9 439
U1 0
U2 10
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUL 7
PY 1994
VL 370
IS 6484
BP 68
EP 71
DI 10.1038/370068a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NV711
UT WOS:A1994NV71100061
PM 8015610
DA 2026-03-10
ER

PT J
AU HU, EM
   HUANG, JS
   GILMORE, G
   COWIE, LL
AF HU, EM
   HUANG, JS
   GILMORE, G
   COWIE, LL
TI AN UPPER LIMIT ON THE DENSITY OF LOW-MASS STARS IN THE GALACTIC HALO
SO NATURE
LA English
DT Article
ID faintest stars; standard stars; brown dwarfs; galaxy; photometry; passbands; models
AB DESPITE the evidence for substantial amounts of dark matter in the haloes of galaxies(1,2), its nature is still unknown. Gravitational microlensing of light from a nearby galaxy by objects in the Galactic halo with masses of about 0.1 solar masses was reported recently(3,4). If these objects are baryonic, low-mass stars seem the most probable candidates. But extrapolation of the locally observed distribution of stellar masses(5,7) to this range suggests that such low-mass stars comprise an insignificant fraction of the Galactic halo, so that microlensing events due to 0.1-solar-mass stars should be rare. Here we report the results of a search for very low-mass stars at high galactic latitudes. Using their near-infrared colours to estimate their intrinsic luminosities, we conclude that very little of the dark matter in the halo of the Milky Way can be made of low-mass hydrogen-burning stars. If the dark matter is baryonic, then we predict that further searches for microlensing events will see a large number of events corresponding to masses of less than 0.07 solar masses.
C1 UNIV CAMBRIDGE,INST ASTRON,CAMBRIDGE CB3 0HA,ENGLAND.
C3 University of Cambridge
RP HU, EM (corresponding author), UNIV HAWAII,INST ASTRON,2680 WOODLAWN DR,HONOLULU,HI 96822, USA.
NR 26
TC 28
Z9 28
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 493
EP 495
DI 10.1038/371493a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900047
DA 2026-03-10
ER

PT J
AU REESE, JC
   APONE, L
   WALKER, SS
   GRIFFIN, LA
   GREEN, MR
AF REESE, JC
   APONE, L
   WALKER, SS
   GRIFFIN, LA
   GREEN, MR
TI YEAST TAF(II)S IN A MULTISUBUNIT COMPLEX REQUIRED FOR ACTIVATED TRANSCRIPTION
SO NATURE
LA English
DT Article
ID tata-binding protein; polymerase-ii transcription; saccharomyces-cerevisiae; crystal-structure; dna; subunit; invitro; gene; tbp
AB IN higher eukaryotes the RNA polymerase II transcription factor TFIID is composed of a TATA-box-binding protein (TBP) and a set of tightly bound polypeptides, designated TBP-associated fao tors (TAF(II)s). One or more TAF(II)s are coactivators that are required for activated but not basal transcription(1-3). The eukaryotic transcription machinery is highly conserved and it is therefore puzzling that TAF(II)s have aot been identified in yeast. Here we use TBP as a protein-affinity ligand to isolate from yeast a multi-subunit complex that is required specifically for activated transcription by RNA polymerase II. Microsequence analysis and cloning of two subunits of this complex reveal that they are the homologues of known mammalian and Drosophila TAF(II)s. The genes encoding these two yeast TAF(II)s are essential, suggesting that activated transcription is required for viability of Saccharomyces cerevisiae.
RP REESE, JC (corresponding author), UNIV MASSACHUSETTS, MED CTR, HOWARD HUGHES MED INST, PROGRAM MOLEC MED, 373 PLANTAT ST, WORCESTER, MA 01605 USA.
NR 22
TC 155
Z9 166
U1 0
U2 0
PU NATURE PORTFOLIO
PI BERLIN
PA HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD OCT 6
PY 1994
VL 371
IS 6497
BP 523
EP 527
DI 10.1038/371523a0
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PK589
UT WOS:A1994PK58900058
PM 7935765
DA 2026-03-10
ER

PT J
AU TAKESHIMA, H
   IINO, M
   TAKEKURA, H
   NISHI, M
   KUNO, J
   MINOWA, O
   TAKANO, H
   NODA, T
AF TAKESHIMA, H
   IINO, M
   TAKEKURA, H
   NISHI, M
   KUNO, J
   MINOWA, O
   TAKANO, H
   NODA, T
TI EXCITATION-CONTRACTION UNCOUPLING AND MUSCULAR DEGENERATION IN MICE LACKING FUNCTIONAL SKELETAL-MUSCLE RYANODINE-RECEPTOR GENE
SO NATURE
LA English
DT Article
ID calcium release channel; sarcoplasmic-reticulum; ca-2+ release; molecular-cloning; targeted mutation; myogenin gene; dna; cdna; inactivation; expression
AB CONTRACTION of skeletal muscle is triggered by the release of Ca2+ from the sarcoplasmic reticulum (SR) after depolarization of transverse tubules(1,2). The ryanodine receptor exists as a 'foot' protein in the junctional gap between the sarcoplasmic reticulum and the transverse tubule in skeletal muscle, and is proposed to function as a calcium-release channel during excitation-contraction (E-C) coupling(3-6). Previous complementary DNA-cloning studies have defined three distinct subtypes of the ryanodine receptor in mammalian tissues, namely skeletal muscle, cardiac and brain types(7-12). We report here mice with a targeted mutation in the skeletal muscle ryanodine receptor gene. Mice homozygous for the mutation die perinatally with gross abnormalities of the skeletal muscle. The contractile response to electrical stimulation under physiological conditions is totally abolished in the mutant muscle, although ryanodine receptors other than the skeletal-muscle type seem to exist because the response to caffeine is retained. Our results show that the skeletal muscle ryanodine receptor is essential for both muscular maturation and E-C coupling, and also imply that the function of the skeletal muscle ryanodine receptor during E-C coupling cannot be substituted by other subtypes of the receptor.
C1 INT INST ADV STUDIES,KYOTO 604,JAPAN.
   UNIV TOKYO,FAC MED,DEPT PHARMACOL,BUNKYO KU,TOKYO 113,JAPAN.
   NATL INST FITNESS & SPORTS,DEPT PHYSIOL,KANOYA,KAGOSHIMA 89123,JAPAN.
   JAPANESE FDN CANC RES,INST CANC,DEPT CELL BIOL,TOSHIMA KU,TOKYO 170,JAPAN.
C3 University of Tokyo; National Institute Fitness & Sports Kanoya; Japanese Foundation for Cancer Research
NR 34
TC 339
Z9 370
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JUN 16
PY 1994
VL 369
IS 6481
BP 556
EP 559
DI 10.1038/369556a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NR294
UT WOS:A1994NR29400048
PM 7515481
DA 2026-03-10
ER

PT J
AU KEIL, RG
   MONTLUCON, DB
   PRAHL, FG
   HEDGES, JI
AF KEIL, RG
   MONTLUCON, DB
   PRAHL, FG
   HEDGES, JI
TI SORPTIVE PRESERVATION OF LABILE ORGANIC-MATTER IN MARINE-SEDIMENTS
SO NATURE
LA English
DT Article
ID amino-acids; clay-minerals; adsorption; carbon
AB ORGANIC matter preserved in marine sediments provides a molecular record of marine biological processes(1), accounts for approximately 20% of all carbon burial(2) and plays a key role in balancing the long-term flux of oxygen to the atmosphere(3). Only recently has it been appreciated that more than 90% of the organic matter preserved in most marine sediments is intimately associated with mineral surfaces(4). Little is known, however, of the effect that sorption to mineral surfaces might have in controlling either the lability or-quantity of-organic matter in the marine sedimentary record. The preserved organic material could be either intrinsically stable, or stabilized through interactions with mineral matrices. We show here that sorption of organic matter to mineral surfaces in marine sediments stabilizes the component molecules, slowing remineralization rates by up to five orders of magnitude. Sorptive protection can therefore account for the enigmatic preservation of intrinsically labile molecules such as amino acids and simple sugars in marine deposits(5,6) and links the preservation of organic carbon in marine sediments to the deposition of mineral surfaces.
C1 OREGON STATE UNIV,COLL OCEANOG,CORVALLIS,OR 97331.
C3 Oregon State University
RP KEIL, RG (corresponding author), UNIV WASHINGTON,SCH OCEANOG,WB-10,SEATTLE,WA 98195, USA.
NR 18
TC 669
Z9 741
U1 6
U2 211
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 18
PY 1994
VL 370
IS 6490
BP 549
EP 552
DI 10.1038/370549a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PC537
UT WOS:A1994PC53700052
DA 2026-03-10
ER

PT J
AU CAVA, RJ
   TAKAGI, H
   BATLOGG, B
   ZANDBERGEN, HW
   KRAJEWSKI, JJ
   PECK, WF
   VANDOVER, RB
   FELDER, RJ
   SIEGRIST, T
   MIZUHASHI, K
   LEE, JO
   EISAKI, H
   CARTER, SA
   UCHIDA, S
AF CAVA, RJ
   TAKAGI, H
   BATLOGG, B
   ZANDBERGEN, HW
   KRAJEWSKI, JJ
   PECK, WF
   VANDOVER, RB
   FELDER, RJ
   SIEGRIST, T
   MIZUHASHI, K
   LEE, JO
   EISAKI, H
   CARTER, SA
   UCHIDA, S
TI SUPERCONDUCTIVITY AT 23-K IN YTTRIUM PALLADIUM BORIDE CARBIDE
SO NATURE
LA English
DT Article
ID films
AB COPPER oxide compounds have dominated superconductivity research since 1986 because of their very high transition temperatures (T(c)s). In contrast, no new families of high-T(c) intermetallic compounds have been discovered since the A15-type Nb3X compounds were first reported in 19531. The intermetallics with highest T(c)s have all been based on niobium, with the highest T(c)s being 20.7 K for bulk Nb3Ga and 23.2 K for sputtered films of Nb3Ge (refs 2, 3). Here we report the observation of superconductivity at 23 K in a multiple-phase bulk sample of a quaternary intermetallic, yttrium palladium boride carbide. This is higher than any T(c) reported previously for a bulk intermetallic compound. Although the materials are not yet single-phase, the superconducting volume fraction is large. We propose that this compound may represent the first of a new family of superconducting intermetallics with relatively high T(c)s.
C1 UNIV TOKYO,DEPT APPL PHYS,TOKYO 113,JAPAN.
   DELFT UNIV TECHNOL,NATL CTR HIGH RESOLUT ELECTRON MICROSCOPY,DELFT,NETHERLANDS.
C3 University of Tokyo; Delft University of Technology
RP CAVA, RJ (corresponding author), AT&T BELL LABS,MURRAY HILL,NJ 07974, USA.
NR 9
TC 557
Z9 569
U1 3
U2 95
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 13
PY 1994
VL 367
IS 6459
BP 146
EP 148
DI 10.1038/367146a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MQ780
UT WOS:A1994MQ78000051
DA 2026-03-10
ER

PT J
AU SUNDSTROM, L
AF SUNDSTROM, L
TI SEX-RATIO BIAS, RELATEDNESS ASYMMETRY AND QUEEN MATING FREQUENCY IN ANTS
SO NATURE
LA English
DT Article
ID social hymenoptera; genetic relatedness; investment ratios; allocation; evolution; insects; competition; patterns; colony; workers
AB HAMILTON's rule and the principle of inclusive fitness' provide a theoretical basis for understanding the evolution of social behaviour, and a framework for predicting reproductive characteristics of social insect colonies2-4. Sex allocation in social insects (especially ants) has become a central factor in tests of inclusive fitness theory5-9. The most powerful such test is the analysis of individual colonies where the predicted sex allocation varies depending on variation in worker fitness functions10,11.  Recently developed models5,12 predict that workers may enhance their inclusive fitness by biasing sex ratios in response to the degree of relatedness asymmetry in each colony. Here I provide the first empirical evidence of facultative sex ratio biasing in response to relatedness asymmetries caused by inter-colony variations in queen mating frequencies. In a Finnish population of the ant Formica truncorum, colonies have a single queen mated to one or several males. Colonies show a bimodal distribution of sex ratios, with a significantly greater proportion of males in colonies headed by a multiply mated queen.
RP SUNDSTROM, L (corresponding author), UNIV HELSINKI,DEPT ZOOL,POB 17,SF-00014 HELSINKI,FINLAND.
NR 30
TC 187
Z9 192
U1 0
U2 62
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD JAN 20
PY 1994
VL 367
IS 6460
BP 266
EP 267
DI 10.1038/367266a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MR494
UT WOS:A1994MR49400054
DA 2026-03-10
ER

PT J
AU HARTGERS, WA
   DAMSTE, JSS
   REQUEJO, AG
   ALLAN, J
   HAYES, JM
   DELEEUW, JW
AF HARTGERS, WA
   DAMSTE, JSS
   REQUEJO, AG
   ALLAN, J
   HAYES, JM
   DELEEUW, JW
TI EVIDENCE FOR ONLY MINOR CONTRIBUTIONS FROM BACTERIA SEDIMENTARY ORGANIC-CARBON
SO NATURE
LA English
DT Article
ID basin; photosynthesis; distributions; hydrocarbons; origins; sulfur; shale
AB BECAUSE their molecular signatures are often prominent in extracts of sediments, bacteria are thought to be important contributors to petroleum source beds(1). It has been shown recently(2,3), however, that abundances of biomarkers do not always reflect relative contributions to sedimentary organic carbon (C-org). The contribution of photosynthetic green sulphur bacteria to sediments can be assessed effectively because the diagenetic products of distinctive carotenoids from these organisms occur widely(4-11) and their biomass is isotopically labelled, being enriched in C-13 (refs 11, 13). We show here that, although sediments and oils from the Western Canada and Williston basins contain prominent biomarkers of photosynthetic bacteria, the absence of C-13 enrichment in the total C-org requires that the bacterial contribution is in fact minimal. Although the importance of bacterial reworking of sedimentary debris cannot be doubted(14), we argue that our findings, when considered in conjunction with those from other settings, suggest that bacterial biomass may commonly represent only a minor component of total C-org in carbonaceous rocks.
C1 TEXAS A&M UNIV,GEOCHEM & ENVIRONV RES GRP,COLLEGE STN,TX 77845.
   ESSO RESOURCES CANADA LTD,CALGARY T2P 0H6,AB,CANADA.
   INDIANA UNIV,DEPT CHEM,BIOGEOCHEM LABS,BLOOMINGTON,IN 47405.
   INDIANA UNIV,DEPT GEOL SCI,BIOGEOCHEM LABS,BLOOMINGTON,IN 47405.
C3 Texas A&M University System; Texas A&M University College Station; Indiana University System; Indiana University Bloomington; Indiana University System; Indiana University Bloomington
RP HARTGERS, WA (corresponding author), NETHERLANDS INST SEA RES,DIV MARINE BIOGEOCHEM,POB 59,1790 AB DEN BURG,NETHERLANDS.
NR 30
TC 78
Z9 83
U1 0
U2 9
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 224
EP 227
DI 10.1038/369224a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700053
PM 11539490
DA 2026-03-10
ER

PT J
AU ABRAHAMS, JP
   LESLIE, AGW
   LUTTER, R
   WALKER, JE
AF ABRAHAMS, JP
   LESLIE, AGW
   LUTTER, R
   WALKER, JE
TI STRUCTURE AT 2.8-ANGSTROM RESOLUTION OF F1-ATPASE FROM BOVINE HEART-MITOCHONDRIA
SO NATURE
LA English
DT Article
ID atp synthase; beta-subunit; oxidative-phosphorylation; electron-microscopy; crystal-structure; escherichia-coli; f1-atpase; protein; binding; mechanism
AB In the crystal structure of bovine mitochondrial F-1-ATPase determined at 2.8 Angstrom resolution, the three catalytic beta-subunits differ in conformation and in the bound nucleotide. The structure supports a catalytic mechanism in intact ATP synthase in which the three catalytic subunits are in different states of the catalytic cycle at any instant. Interconversion of the states may be achieved by rotation of the alpha(3) beta(3) subassembly relative to an alpha-helical domain of the gamma-subunit.
C1 MRC, MOLEC BIOL LAB, CAMBRIDGE CB2 2QH, ENGLAND.
C3 MRC Laboratory Molecular Biology
NR 50
TC 2830
Z9 3099
U1 5
U2 256
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 1476-4687
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 621
EP 628
DI 10.1038/370621a0
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000041
PM 8065448
DA 2026-03-10
ER

PT J
AU KO, MKW
   SZE, ND
   PRATHER, MJ
AF KO, MKW
   SZE, ND
   PRATHER, MJ
TI BETTER PROTECTION OF THE OZONE-LAYER
SO NATURE
LA English
DT Article
ID stratospheric ozone; depletion; impact
C1 UNIV CALIF IRVINE,DEPT EARTH SYST SCI,IRVINE,CA 92717.
C3 University of California System; University of California Irvine
RP KO, MKW (corresponding author), ATMOSPHER & ENVIRONM RES INC,840 MEM DR,CAMBRIDGE,MA 02139, USA.
NR 16
TC 17
Z9 18
U1 0
U2 4
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD FEB 10
PY 1994
VL 367
IS 6463
BP 505
EP 508
DI 10.1038/367505a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MV863
UT WOS:A1994MV86300029
DA 2026-03-10
ER

PT J
AU FINER, JT
   SIMMONS, RM
   SPUDICH, JA
AF FINER, JT
   SIMMONS, RM
   SPUDICH, JA
TI SINGLE MYOSIN MOLECULE MECHANICS - PICONEWTON FORCES AND NANOMETER STEPS
SO NATURE
LA English
DT Article
ID rabbit psoas muscle; kinesin molecules; sliding distance; skeletal-muscle; actin filament; movement; invitro; fibers; contraction; atp
AB A new in vitro assay using a feedback enhanced laser trap system allows direct measurement of force and displacement that results from the interaction of a single myosin molecule with a single suspended actin filament. Discrete stepwise movements averaging ai nm were seen under conditions of low load, and single force transients averaging 3-4 pN were measured under isometric conditions. The magnitudes of the single forces and displacements are consistent with predictions of the conventional swinging-crossbridge model of muscle contraction.
C1 STANFORD UNIV,SCH MED,BECKMAN CTR,DEPT BIOCHEM,STANFORD,CA 94305.
   STANFORD UNIV,SCH MED,BECKMAN CTR,DEPT BIOL,STANFORD,CA 94305.
   KINGS COLL LONDON,RANDALL INST,MRC MUSCLE & CELL MOTIL UNIT,LONDON WC2B 5RL,ENGLAND.
C3 Stanford University; Stanford University; University of London; King's College London
FU Wellcome Trust Funding Source: Medline
NR 45
TC 1615
Z9 1866
U1 3
U2 237
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 10
PY 1994
VL 368
IS 6467
BP 113
EP 119
DI 10.1038/368113a0
PG 7
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NA030
UT WOS:A1994NA03000055
PM 8139653
DA 2026-03-10
ER

PT J
AU STRYNADKA, NCJ
   JENSEN, SE
   JOHNS, K
   BLANCHARD, H
   PAGE, M
   MATAGNE, A
   FRERE, JM
   JAMES, MNG
AF STRYNADKA, NCJ
   JENSEN, SE
   JOHNS, K
   BLANCHARD, H
   PAGE, M
   MATAGNE, A
   FRERE, JM
   JAMES, MNG
TI STRUCTURAL AND KINETIC CHARACTERIZATION OF A BETA-LACTAMASE-INHIBITOR PROTEIN
SO NATURE
LA English
DT Article
ID clavulanic acid; resolution; resistance; refinement
AB THE past decade has seen an alarming worldwide increase in resistance to beta-lactam antibiotics among many pathogenic bacteria1, which is due mainly to plasmid- or chromosomally encoded beta-lactamases that specifically cleave penicillin and cephalosporins, rendering them inactive. There is therefore a need to develop new strategies in the design of effective inhibitors of beta-lactamase. All the small-molecule inhibitors in clinical use are not very effective and are rapidly degraded2,3. Furthermore, newly characterized mutants of the plasmid-mediated beta-lactamase TEM-1 are highly resistant to these small-molecule inhibitors, including clavulanic acid and tazobactam4. It has been shown that Streptomyces clavuligerus produces an exocellular beta-lactamase inhibitory protein (BLIP; M(r) 17.5 K)5. Here we present data defining BLIP as the most effective known inhibitor of a variety of beta-lactamases, with K(i) values in the subnanomolar to picomolar range. To identify those features in BLIP that make it such a potent inhibitor, we have determined its molecular structure at 2.1 angstrom resolution. BLIP is a relatively flat molecule with a unique fold, comprising a tandem repeat of a 76-amino-acid domain. Each domain consists of a helix-loop-helix motif that packs against a four-stranded antiparallel beta-sheet (Fig. 1a). To our knowledge, BLIP is the first example of a protein inhibitor having two similarly folded domains that interact with and inhibit a single target enzyme.
C1 UNIV ALBERTA,DEPT BIOCHEM,MRC,PROT STRUCT & FUNCT GRP,EDMONTON T6G 2G7,ALBERTA,CANADA.
   UNIV ALBERTA,DEPT MICROBIOL,EDMONTON T6G 2E9,ALBERTA,CANADA.
   F HOFFMANN LA ROCHE & CO LTD,DEPT PRECLIN RES PHARMADIV INFECT DIS,CH-4002 BASEL,SWITZERLAND.
   STATE UNIV LIEGE,ENZYMOL LAB,B-4000 LIEGE,BELGIUM.
   STATE UNIV LIEGE,CTR PROT ENGN,B-4000 LIEGE,BELGIUM.
C3 University of Alberta; University of Alberta; Roche Holding; University of Liege; University of Liege
NR 22
TC 118
Z9 138
U1 0
U2 15
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 14
PY 1994
VL 368
IS 6472
BP 657
EP 660
DI 10.1038/368657a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NF392
UT WOS:A1994NF39200067
PM 8145854
DA 2026-03-10
ER

PT J
AU MAKELA, TP
   TASSAN, JP
   NIGG, EA
   FRUTIGER, S
   HUGHES, GJ
   WEINBERG, RA
AF MAKELA, TP
   TASSAN, JP
   NIGG, EA
   FRUTIGER, S
   HUGHES, GJ
   WEINBERG, RA
TI A CYCLIN ASSOCIATED WITH THE CDK-ACTIVATING KINASE MO15
SO NATURE
LA English
DT Article
ID protein-kinase; catalytic subunit; cell-cycle; phosphorylation; p34cdc2; cdc2; p40(mo15); p34(cdc2); invitro; yeast
AB THE eukaryotic cell cycle is regulated by the sequential activation of cyclin-dependent kinases (CDKs)(1). CDK activation is dependent on cyclin binding(2-4) and phosphorylation of a conserved threonine (T161 in Cdc2)(5-9) mediated by the CDK-activating kinase CAK(9). A CDK-related kinase, MO15 (ref. 10), has been identified as the catalytic submit of CAK (refs 11-13). Here we use a yeast two-hybrid screen to show that a new human cyclin (cyclin H) is a MO15-associated protein. Cyclin H is a major MO15 partner in vivo and enhances the kinase activity of MO15 towards Cdk2/cyclin A. These findings demonstrate that a cyclin/kinase complex can function as a regulator of other cyclin/kinase complexes, and suggest that cyclin/kinase cascades may exist.
C1 WHITEHEAD INST BIOMED RES,CAMBRIDGE,MA 02142.
   SWISS INST EXPTL CANC RES,CH-1066 EPALINGES,SWITZERLAND.
   UNIV GENEVA,CTR MED UNIV,DEPT BIOCHIM MED,CH-1211 GENEVA 4,SWITZERLAND.
C3 Massachusetts Institute of Technology (MIT); Whitehead Institute; Swiss Institute Experimental Cancer Research; University of Geneva
NR 26
TC 245
Z9 262
U1 0
U2 2
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 15
PY 1994
VL 371
IS 6494
BP 254
EP 257
DI 10.1038/371254a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PG290
UT WOS:A1994PG29000055
PM 8078587
DA 2026-03-10
ER

PT J
AU NEVIN, WA
   YAMAGISHI, H
   YAMAGUCHI, M
   TAWADA, Y
AF NEVIN, WA
   YAMAGISHI, H
   YAMAGUCHI, M
   TAWADA, Y
TI EMISSION OF BLUE-LIGHT FROM HYDROGENATED AMORPHOUS-SILICON CARBIDE
SO NATURE
LA English
DT Article
ID carbon alloy; luminescence
AB THE development of new electroluminescent materials is of current technological interest for use in flat-screen full-colour displays1. For such applications, amorphous inorganic semiconductors appear particularly promising, in view of the ease with which uniform films with good mechanical and electronic properties can be deposited over large areas2. Luminescence has been reported1 in the red-green part of the spectrum from amorphous silicon carbide prepared from gas-phase mixtures of silane and a carbon-containing species (usually methane or ethylene). But it is not possible to achieve blue luminescence by this approach. Here we show that the use of an aromatic species-xylene-as the source of carbon during deposition results in a form of amorphous silicon carbide that exhibits strong blue luminescence. The underlying structure of this material seems to be an unusual combination of an inorganic silicon carbide lattice with a substantial 'organic' pi-conjugated carbon system, the latter dominating the emission properties. Moreover, the material can be readily doped with an electron acceptor in a manner similar to organic semiconductors3, and might therefore find applications as a conductivity- or colour-based chemical sensor.
RP NEVIN, WA (corresponding author), KANEKA CORP,CENT RES LABS,1-2-80 YOSHIDA CHO,HYOGO,KOBE 652,JAPAN.
NR 15
TC 72
Z9 78
U1 0
U2 22
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD APR 7
PY 1994
VL 368
IS 6471
BP 529
EP 531
DI 10.1038/368529a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NE335
UT WOS:A1994NE33500048
DA 2026-03-10
ER

PT J
AU COOMBS, J
AF COOMBS, J
TI QUALITY STANDARDS AND THE JOB MARKET
SO NATURE
LA English
DT Article
AB Adoption of quality standards, increased legislation and the need to prove due diligence are generating a growing market for personnel with skills in quality control, quality assurance and regulatory matters. This assessment comes from a company offering recruitment services in the field.
RP COOMBS, J (corresponding author), CPL SCI LTD,NEWBURY,BERKS,ENGLAND.
NR 0
TC 0
Z9 0
U1 1
U2 1
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD AUG 25
PY 1994
VL 370
IS 6491
BP 673
EP 674
DI 10.1038/370673a0
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PD310
UT WOS:A1994PD31000056
PM 8065456
DA 2026-03-10
ER

PT J
AU WANG, LY
   ORSER, BA
   BRAUTIGAN, DL
   MACDONALD, JF
AF WANG, LY
   ORSER, BA
   BRAUTIGAN, DL
   MACDONALD, JF
TI REGULATION OF NMDA RECEPTORS IN CULTURED HIPPOCAMPAL-NEURONS BY PROTEIN PHOSPHATASE-1 AND PHOSPHATASE-2A
SO NATURE
LA English
DT Article
ID mouse-brain neurons; synaptic plasticity; potassium channel; okadaic acid; calyculin-a; phosphorylation; kinase; modulation; glycine; dephosphorylation
AB PHOSPHORYLATION Of glutamate receptors is probably an important mechanism for modulating excitatory transmission(1-4). However, there is little direct evidence to indicate which protein phosphatases can dephosphorylate glutamate(5) or other ligandgated channels(6), although it is known that protein phosphatases 1 and 2A play a major part in modulating voltage(7-10) and second-messenger-gated channels(11). Here we report that in cultured hippocampal neurons, the N-methgl-D-aspartate (NMDA) receptor can be regulated by endogenous and exogenous serine/threonine protein phosphatases. Phosphatase inhibitors enhanced NMDA currents recorded using the perforated patch technique(13) or in cell-attached patches, whereas protein phosphatases 1 or 2A decreased the open probability of these channels in inside-out patches.
C1 UNIV TORONTO,DEPT PHARMACOL,TORONTO M5S 1A8,ON,CANADA.
   UNIV TORONTO,DEPT ANAESTHESIA,TORONTO M5S 1A8,ON,CANADA.
   BROWN UNIV,DIV BIOL & MED,PROVIDENCE,RI 02912.
C3 University of Toronto; University of Toronto; Brown University
RP WANG, LY (corresponding author), UNIV TORONTO,DEPT PHYSIOL,MED SCI BLDG,TORONTO M5S 1A8,ON,CANADA.
NR 29
TC 187
Z9 204
U1 0
U2 6
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAY 19
PY 1994
VL 369
IS 6477
BP 230
EP 232
DI 10.1038/369230a0
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA NM067
UT WOS:A1994NM06700055
PM 8183343
DA 2026-03-10
ER

PT J
AU NGHIEM, P
   OLLICK, T
   GARDNER, P
   SCHULMAN, H
AF NGHIEM, P
   OLLICK, T
   GARDNER, P
   SCHULMAN, H
TI INTERLEUKIN-2 TRANSCRIPTIONAL BLOCK BY MULTIFUNCTIONAL CA2+/CALMODULIN KINASE
SO NATURE
LA English
DT Article
ID dependent protein-kinase; lymphocyte-t activation; calmodulin kinase; clonal anergy; cam kinase; calcium; expression; calcineurin; transactivation; promoter
AB IN the presence of costimulation(1), Ca2+ influx in T cells leads to activation (transcription of interleukin-2; ref 2) via calcineurin(3,4). In the absence of costimulation, Ca2+ influx results in anergy (interleukin-2 transcriptional block(5)) through an unknown mechanism. Specific attenuation of interleukin-2 transcriptional induction occurs in Jurkat T cells following pretreatment with a Ca2+ ionophore. A >90% block of inducible interleukin-2 reporter gene activity was initiated by transfection of a constitutively active mutant of multifunctional Ca2+/calmodulin-dependent protein kinase (CaM kinase or CaM kinase II)(6), but not by constitutive mutants of CaM kinase IV, calcineurin or protein kinase C. The block was complete six hours after kinase transfection and showed specificity for interleukin-2; there was no change in beta-actin transcription or in c-fos transcription induced by phorbol myristyl acetate, and a Rous sarcoma virus promoter was stimulated threefold. Multifunctional CaM kinase also attenuated interleukin-2 activation by calcineurin plus phorbol ester. T-cell receptor signalling activates multifunctional CaM kinase. These findings suggest that two Ca2+/calmodulin-responsive enzymes, multifunctional CaM kinase and calcineurin, could mediate the divergent effects of Ca2+ signals in T-lymphocyte regulation.
C1 STANFORD UNIV,SCH MED,DEPT NEUROBIOL,STANFORD,CA 94305.
   STANFORD UNIV,SCH MED,DEPT MOLEC PHARMACOL & MED,STANFORD,CA 94305.
C3 Stanford University; Stanford University
NR 30
TC 97
Z9 103
U1 0
U2 0
PU MACMILLAN MAGAZINES LTD
PI LONDON
PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD SEP 22
PY 1994
VL 371
IS 6495
BP 347
EP 350
DI 10.1038/371347a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA PH254
UT WOS:A1994PH25400057
PM 8090206
DA 2026-03-10
ER

PT J
AU FEELISCH, M
   POEL, MT
   ZAMORA, R
   DEUSSEN, A
   MONCADA, S
AF FEELISCH, M
   POEL, MT
   ZAMORA, R
   DEUSSEN, A
   MONCADA, S
TI UNDERSTANDING THE CONTROVERSY OVER THE IDENTITY OF EDRF
SO NATURE
LA English
DT Article
ID nitric-oxide; relaxing factor; biological-activity; endothelial-cells; s-nitrosocysteine; mechanism; vasodilator; relaxation; nitroxyl
AB THIRTEEN years after its discovery(1), there is still controversy over the chemical identity of endothelium-derived relaxing factor (EDRF). Although pharmacological and chemical evidence indicates that EDRF is nitric oxide(2), other candidates, including S-nitrosocysteine(3,4), complex(5), nitroxyl(6) and hydroxylamine(7), have been proposed to account for the vasorelaxant properties of EDRF. Such diverse compounds should differ in their stability and in reactivity with oxyhaemoglobin and with redox-active nucleophiles such as thiols. Here we use a bioassay to compare the pharmacodynamic profiles of these and other compounds with those of nitric oxide and EDRF. We find that some S-nitrosothiols, dinitrosyl-iron-cysteine complex, sodium nitroxyl and hydroxylamine can be eliminated as candidates as they are more stable than EDRF and less susceptible to inhibition by oxyhaemoglobin. Co-infusion of cysteine revealed major differences between the remaining candidates because it reduced the effect of authentic nitric oxide and EDRF on the bioassay tissues but enhanced the survival of S-nitrosocysteine and S-nitroso-cysteamine. Our results further support the evidence that EDRF, the pharmacological entity described by Furchgott and Zawadzki(1), is nitric oxide.
C1 HEINRICH HEINE UNIV, CTR PHYSIOL, D-40225 DUSSELDORF, GERMANY.
   WELLCOME RES LABS, BECKENHAM BR3 3BS, KENT, ENGLAND.
C3 Heinrich Heine University Dusseldorf; GlaxoSmithKline; Glaxosmithkline United Kingdom
RP FEELISCH, M (corresponding author), SCHWARZ PHARMA AG, DEPT PHARMACOL, D-40789 MONHEIM, GERMANY.
NR 21
TC 230
Z9 248
U1 0
U2 14
PU NATURE PUBLISHING GROUP
PI LONDON
PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
SN 0028-0836
EI 
J9 NATURE
JI Nature
PD MAR 3
PY 1994
VL 368
IS 6466
BP 62
EP 65
DI 10.1038/368062a0
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA MY569
UT WOS:A1994MY56900053
PM 8107883
DA 2026-03-10
ER

