Structure of superhard tungsten tetraboride: a missing link between MB2 and MB12 higher borides.

abstract：:The dnaX gene (previously called dnaZX) of Escherichia coli has only one open reading frame for a 71-kDa polypeptide from which two distinct DNA polymerase III holoenzyme subunits, tau (71 kDa) and gamma (47 kDa), are produced. To determine how the gamma subunit is generated, we examined the influence of mutations in ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tsuchihashi Z,Kornberg A

更新日期：1990-04-01 00:00:00

abstract：:Under anesthesia with sodium pentobarbital, the sciatic nerves of rats were transected bilaterally, and a catheter was inserted into the central end of the left renal artery. After an initial flush, an Alzet pump was attached to the catheter, containing various concentrations of glycyl-L-glutamine (Gly-Gln), methylpre...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Koelle GB,Han MS

更新日期：1990-12-01 00:00:00

abstract：:In multiple binding of ligands to a protein, the binding sites may seem to behave as if they are partitioned equally between two modalities. This paper analyzes three different molecular situations in which two actual assemblages appear: (i) two classes of sites exist at the outset in the ligand-free macromolecule; (i...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Klotz IM,Hunston DL

更新日期：1977-11-01 00:00:00

abstract：:In many human cancers, tumor-specific chromosomal rearrangements are known to create chimeric products with the ability to transform cells. The EWS/WT1 protein is such a fusion product, resulting from a t(11;22) chromosomal translocation in desmoplastic small round cell tumors, where 265 aa from the EWS amino terminus...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kim J,Lee JM,Branton PE,Pelletier J

更新日期：1999-12-07 00:00:00

abstract：:Ras CAAX (C = cysteine, A = aliphatic amino acid, and X = any amino acid) peptidomimetic inhibitors of farnesyl protein transferase suppress Ras-dependent cell transformation by preventing farnesylation of the Ras oncoprotein. These compounds are potential anticancer agents for tumors associated with Ras mutations. Th...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kauffmann RC,Qian Y,Vogt A,Sebti SM,Hamilton AD,Carthew RW

更新日期：1995-11-21 00:00:00

abstract：:An examination of life expectancy in 1963 reveals twin peaks in the empirical distribution across countries: one group of countries clustered around a life expectancy of 40 years and a second group clustered around a life expectancy of 65 years. By 2003, the mode of each cluster had moved up by approximately 10 years....

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Bloom DE,Canning D

更新日期：2007-10-09 00:00:00

abstract：:Interleukin 3 (IL-3) stimulates the proliferation and differentiation of various haematopoietic progenitor cells. Recently, IL-3 and other cytokines were reported to exert a neurotrophic activity and to be associated with neurological disorders, suggesting their complex role in the central nervous system. We now show ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Chavany C,Vicario-Abejón C,Miller G,Jendoubi M

更新日期：1998-09-15 00:00:00

abstract：:Assessing temporal variability in extreme rainfall events before the historical era is complicated by the sparsity of long-term "direct" storm proxies. Here we present a 2,200-y-long, accurate, and precisely dated record of cave flooding events from the northwest Australian tropics that we interpret, based on an integ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Denniston RF,Villarini G,Gonzales AN,Wyrwoll KH,Polyak VJ,Ummenhofer CC,Lachniet MS,Wanamaker AD Jr,Humphreys WF,Woods D,Cugley J

更新日期：2015-04-14 00:00:00

abstract：:ATP-binding cassette (ABC) transporters use ATP to drive solute transport across biological membranes. Members of this superfamily have crucial roles in cell physiology, and some of the transporters are linked to severe diseases. However, understanding of the transport mechanism, especially of human ABC exporters, is ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Zollmann T,Moiset G,Tumulka F,Tampé R,Poolman B,Abele R

更新日期：2015-02-17 00:00:00

abstract：:Heat shock (HS) initiates rapid, extensive, and evolutionarily conserved changes in transcription that are accompanied by chromatin decondensation and nucleosome loss at HS loci. Here we have employed in situ Hi-C to determine how heat stress affects long-range chromatin conformation in human and Drosophila cells. We ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Ray J,Munn PR,Vihervaara A,Lewis JJ,Ozer A,Danko CG,Lis JT

更新日期：2019-09-24 00:00:00

abstract：:Copper is an essential metal nutrient that is tightly regulated in the body because loss of its homeostasis is connected to severe diseases such as Menkes and Wilson diseases, Alzheimer's disease, prion disorders, and amyotrophic lateral sclerosis. The complex relationships between copper status and various stages of ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Hirayama T,Van de Bittner GC,Gray LW,Lutsenko S,Chang CJ

更新日期：2012-02-14 00:00:00

abstract：:The hydroxyproline-containing proteins (hyproproteins) synthesized by cultured human fibroblasts have been partially characterized. The hyproprotein extracted from the cell layer was found to be similar to the collagen extracted from skin in the ratio of hydroxyproline to proline, chain composition, solubility, and re...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Layman DL,McGoodwin EB,Martin GR

更新日期：1971-02-01 00:00:00

abstract：:Gecko and many insects have adopted nanoscale fibrillar structures on their feet as adhesion devices. Here, we consider adhesion between a single fiber and a substrate by van der Waals or electrostatic interactions. For a given contact area A, the theoretical pull-off force of the fiber is sigma(th)A where sigma(th) i...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gao H,Yao H

更新日期：2004-05-25 00:00:00

abstract：:The dramatic loss of Kilimanjaro's ice cover has attracted global attention. The three remaining ice fields on the plateau and the slopes are both shrinking laterally and rapidly thinning. Summit ice cover (areal extent) decreased approximately 1% per year from 1912 to 1953 and approximately 2.5% per year from 1989 to...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Thompson LG,Brecher HH,Mosley-Thompson E,Hardy DR,Mark BG

更新日期：2009-11-24 00:00:00

abstract：:PdxB (erythronate 4-phosphate dehydrogenase) is expected to be required for synthesis of the essential cofactor pyridoxal 5'-phosphate (PLP) in Escherichia coli Surprisingly, incubation of the ∆pdxB strain in medium containing glucose as a sole carbon source for 10 d resulted in visible turbidity, suggesting that PLP ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kim J,Flood JJ,Kristofich MR,Gidfar C,Morgenthaler AB,Fuhrer T,Sauer U,Snyder D,Cooper VS,Ebmeier CC,Old WM,Copley SD

更新日期：2019-11-26 00:00:00

abstract：:Cell membrane proteins synthesized after infection of Escherichia coli B with wild-type phage T4 and rIIA mutants were analyzed by dodecyl sulfate-polyacrylamide gel electrophoresis. A protein with an approximate molecular weight of 74,000 is present in membranes isolated from T4r(+)-infected cells, but is not found i...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Ennis HL,Kievitt KD

更新日期：1973-05-01 00:00:00

abstract：:Native cytochrome c (cyt c) has a compact tertiary structure with a hexacoordinated heme iron and functions in electron transport in mitochondria and apoptosis in the cytoplasm. However, the possibility that protein modifications confer additional functions to cyt c has not been explored. Disruption of methionine 80 (...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Godoy LC,Muñoz-Pinedo C,Castro L,Cardaci S,Schonhoff CM,King M,Tórtora V,Marín M,Miao Q,Jiang JF,Kapralov A,Jemmerson R,Silkstone GG,Patel JN,Evans JE,Wilson MT,Green DR,Kagan VE,Radi R,Mannick JB

更新日期：2009-02-24 00:00:00

abstract：:Eye blinking is one of the most frequent human actions. The control of blinking is thought to reflect complex interactions between maintaining clear and healthy vision and influences tied to central dopaminergic functions including cognitive states, psychological factors, and medical conditions. The most imminent cons...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Hoppe D,Helfmann S,Rothkopf CA

更新日期：2018-02-27 00:00:00

abstract：:The herpes simplex virus DNA polymerase consists of two subunits--a catalytic subunit and an accessory subunit, UL42, that increases processivity. Mutations affecting the extreme C terminus of the catalytic subunit specifically disrupt subunit interactions and ablate virus replication, suggesting that new antiviral dr...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Digard P,Williams KP,Hensley P,Brooks IS,Dahl CE,Coen DM

更新日期：1995-02-28 00:00:00

abstract：:Newly translated tubulin molecules undergo a series of complex interactions with nascent chain-binding chaperones, including prefoldin (PFD) and chaperonin-containing TCP-1 (CCT). By screening for oryzalin hypersensitivity, we identified several mutants of Arabidopsis that have lesions in PFD subunits. The pfd6-1 muta...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gu Y,Deng Z,Paredez AR,DeBolt S,Wang ZY,Somerville C

更新日期：2008-11-18 00:00:00

abstract：:The trilaminate vascular architecture provides biochemical regulation and mechanical integrity. Yet regulatory control can be regained after injury without recapitulating tertiary structure. Tissue-engineered (TE) endothelium controls repair even when placed in the perivascular space of injured vessels. It remains unc...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Zani BG,Kojima K,Vacanti CA,Edelman ER

更新日期：2008-05-13 00:00:00

abstract：:Examination of old human lenses indicates that low-molecular-weight alpha crystallin is not present in the inner 30-40%, the nucleus, of the lens. The remainder of such lenses, the periphery, contains normal levels of this protein. This finding is in marked contrast to observations in young lenses, where a large quant...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Roy D,Spector A

更新日期：1976-10-01 00:00:00

abstract：:Old noninbred fly mortality decreases according to the inverse linear law and reduces to a single suborder-specific age. Relative child mortality (the mortality at a given age related to the mortality at 10 years) from 1 mo to 11 years is the same with 8% mean accuracy for all humans, independent of race, country, sex...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Azbel' MY

更新日期：1998-07-21 00:00:00

abstract：:HIV-1 maturation involves conversion of the immature Gag polyprotein lattice, which lines the inner surface of the viral membrane, to the mature capsid protein (CA) lattice, which encloses the viral RNA. Maturation inhibitors such as bevirimat (BVM) bind within six-helix bundles, formed by a segment that spans the jun...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gupta S,Louis JM,Tycko R

更新日期：2020-05-12 00:00:00

abstract：:Positive allosteric modulation of the mu-opioid receptor (MOPr), the site of action of all clinically used opioids, represents a potential approach for the management of pain. We recently reported on positive allosteric modulators of MOPr (mu-PAMs), a class A G protein coupled receptor (GPCR). This study was designed ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Livingston KE,Traynor JR

更新日期：2014-12-23 00:00:00

abstract：:Marine ecosystems are sensitive to stochastic environmental variability, with higher-amplitude, lower-frequency--i.e., "redder"--variability posing a greater threat of triggering large ecosystem changes. Here we show that fluctuations in the Pacific Decadal Oscillation (PDO) index have slowed down markedly over the ob...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Boulton CA,Lenton TM

更新日期：2015-09-15 00:00:00

abstract：:Signal transductions by the dual-function CXCR4 and CCR5 chemokine receptors/HIV type 1 (HIV-1) coreceptors were electrophysiologically monitored in Xenopus laevis oocytes that also coexpressed the viral receptor CD4 and a G protein-coupled inward-rectifying K+ channel (Kir 3.1). Large Kir 3.1-dependent currents gener...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Madani N,Kozak SL,Kavanaugh MP,Kabat D

更新日期：1998-07-07 00:00:00

abstract：:Type 2 diabetes is preceded by the development of insulin resistance, in which the action of insulin is impaired, largely in skeletal muscles. Caveolin-3 (Cav3) is a muscle-specific subtype of caveolin, an example of a scaffolding protein found within membranes. Cav is also known as growth signal inhibitor, although i...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Oshikawa J,Otsu K,Toya Y,Tsunematsu T,Hankins R,Kawabe J,Minamisawa S,Umemura S,Hagiwara Y,Ishikawa Y

更新日期：2004-08-24 00:00:00

abstract：:Leptin is an adipocytokine that plays a key role in the modulation of immune responses and the development and maintenance of inflammation. Circulating levels of leptin are elevated in systemic lupus erythematosus (SLE) patients, but it is not clear whether this association can reflect a direct influence of leptin on ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Lourenço EV,Liu A,Matarese G,La Cava A

更新日期：2016-09-20 00:00:00

abstract：:The sided effects of H+ on Ca2(+)-stimulated K+ transport (the Gardos channel) were studied in human red blood cells. Cells were loaded with Ca2+ during energy depletion with the internal pH adjusted to desired levels prior to treatment with the anion-exchange inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Heinz A,Hoffman JF

更新日期：1990-03-01 00:00:00