Hollow core of Alzheimer's Abeta42 amyloid observed by cryoEM is relevant at physiological pH.

abstract：:The Notch-signaling pathway controls cellular differentiation, including proliferation and cell death in all higher metazoans (including flies and men). Signal transduction through activated Notch involves the CSL group of transcriptional regulators. Notch signals need to be tightly regulated, and in Drosophila they a...

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

authors： Maier D,Nagel AC,Preiss A

更新日期：2002-11-26 00:00:00

abstract：:Twenty-four hours after rats receive choline chloride (20 mmol/kg, by stomach tube) the activity of tyrosine hydroxylase [tyrosine 3-monooxygenase; L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (3-hydroxylating), EC 1.14.16.2] increases by 31% within adrenomedullary chromaffin cells. This treatment also causes...

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

authors： Ulus IH,Hirsch MJ,Wurtman RJ

更新日期：1977-02-01 00:00:00

abstract：:A 24-amino acid residue peptide has been isolated from the Fc region of a human IgG1 myeloma protein. The peptide has associated with it the same ability to induce murine B cells to polyclonally secrete antibody as does the intact Fc fragment. Amino acid composition of the peptide indicates that on a mole/mole basis t...

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

authors： Morgan EL,Hugli TE,Weigle WO

更新日期：1982-09-01 00:00:00

abstract：:p53 is a master regulatory, sequence-specific transcription factor that directly controls expression of over 100 genes in response to various stress signals. Transactivation is generally considered to occur through p53 binding to a consensus response element (RE) composed of two 5'-RRRCWWGYYY-3' decamers. Recently, st...

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

authors： Menendez D,Inga A,Resnick MA

更新日期：2010-01-26 00:00:00

abstract：:The embryonic sites in which progenitors of the hematopoietic lineages first emerge are ideal regions to characterize both the cells and environment needed to initiate blood cell development. For a number of years both the murine yolk sac and embryo have been recognized to contain progenitors of B lymphocytes. However...

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

authors： Cumano A,Furlonger C,Paige CJ

更新日期：1993-07-15 00:00:00

abstract：:Hepatitis C virus (HCV) infects nearly 3% of the population of the world and is a major cause of liver disease. However, the mechanism whereby the virus targets the liver for infection remains unknown, because none of the putative cellular receptors for HCV are both expressed specifically in the liver and capable of b...

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

authors： Gardner JP,Durso RJ,Arrigale RR,Donovan GP,Maddon PJ,Dragic T,Olson WC

更新日期：2003-04-15 00:00:00

abstract：:The CuAAC reaction (click chemistry) has been used in conjunction with solid-phase synthesis to produce catalytically active hairpin ribozymes around 100 nucleotides in length. Cross-strand ligation through neighboring nucleobases was successful in covalently linking presynthesized RNA strands with high efficiency (tr...

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

authors： El-Sagheer AH,Brown T

更新日期：2010-08-31 00:00:00

abstract：:I discuss two exotic objects that must be experimentally identified in chiral superfluids and superconductors. These are (i) the vortex with a fractional quantum number (N = 1/2 in chiral superfluids, and N = 1/2 and N = 1/4 in chiral superconductors), which plays the part of the Alice string in relativistic theories ...

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

authors： Volovik GE

更新日期：2000-03-14 00:00:00

abstract：:Stochasticity alters the nonlinear dynamics of inherently cycling populations. The power spectrum can describe and explain the impacts of stochasticity. We fitted models to short observed time series of flour beetle populations in the frequency domain, then used a well fitting stochastic mechanistic model to generate ...

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

authors： Reuman DC,Desharnais RA,Costantino RF,Ahmad OS,Cohen JE

更新日期：2006-12-05 00:00:00

abstract：:The replication initiator proteins encoded by the pT181 and related plasmids have sequence-specific DNA binding and topoisomerase activities. These proteins create a site-specific nick in one strand of the DNA at the origin of replication that serves as a primer for the initiation of replication. To define the regions...

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

authors： Dempsey LA,Birch P,Khan SA

更新日期：1992-04-01 00:00:00

abstract：:The radial distributions of the Calpha and side-chain atoms in a sample of 13 native proteins have been examined. It is found that there are substantial differences in behavior between different atoms of the same amino acid. In particular, the Calpha atoms of polar residues show no particular preference for being far ...

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

authors： Rackovsky S,Scheraga HA

更新日期：1977-12-01 00:00:00

abstract：:Occurrence of the transversion mutation A.T to C.G is specifically enhanced in Escherichia coli mutT mutants. With the aid of the cloned mutT gene, the MutT protein, which has a molecular mass of 15 kilodaltons, was overproduced and purified to near homogeneity. The protein catalyzes hydrolysis of dGTP to dGMP. dGDP a...

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

authors： Akiyama M,Maki H,Sekiguchi M,Horiuchi T

更新日期：1989-06-01 00:00:00

abstract：:Given their relatively small area, mangroves and their organic sediments are of disproportionate importance to global carbon sequestration and carbon storage. Peat deposition and preservation allows some mangroves to accrete vertically and keep pace with sea-level rise by growing on their own root remains. In this stu...

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

authors： Ezcurra P,Ezcurra E,Garcillán PP,Costa MT,Aburto-Oropeza O

更新日期：2016-04-19 00:00:00

abstract：:Nonnative species richness typically declines along environmental gradients such as elevation. It is usually assumed that this is because few invaders possess the necessary adaptations to succeed under extreme environmental conditions. Here, we show that nonnative plants reaching high elevations around the world are n...

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

authors： Alexander JM,Kueffer C,Daehler CC,Edwards PJ,Pauchard A,Seipel T,MIREN Consortium.

更新日期：2011-01-11 00:00:00

abstract：:Group II intron RNAs self-splice in vitro but only at high salt and/or Mg2+ concentrations and have been thought to require proteins to stabilize their active structure for efficient splicing in vivo. Here, we show that a DEAD-box protein, CYT-19, can by itself promote the splicing and reverse splicing of the yeast aI...

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

authors： Mohr S,Matsuura M,Perlman PS,Lambowitz AM

更新日期：2006-03-07 00:00:00

abstract：:Using cell-based aptamer selection, we have developed a strategy to use the differences at the molecular level between any two types of cells for the identification of molecular signatures on the surface of targeted cells. A group of aptamers have been generated for the specific recognition of leukemia cells. The sele...

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

authors： Shangguan D,Li Y,Tang Z,Cao ZC,Chen HW,Mallikaratchy P,Sefah K,Yang CJ,Tan W

更新日期：2006-08-08 00:00:00

abstract：:The mitotic (or spindle assembly) checkpoint system prevents premature separation of sister chromatids in mitosis. When the checkpoint is turned on, the mitotic checkpoint complex (MCC) inhibits the ubiquitin ligase anaphase-promoting complex/cyclosome (APC/C). MCC is composed of the checkpoint proteins BubR1, Bub3, a...

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

authors： Eytan E,Sitry-Shevah D,Teichner A,Hershko A

更新日期：2013-06-25 00:00:00

abstract：:Mouse lymphocytic cells of the established line GF-14 were allowed to accumulate intracellular 3H-labeled aminoisobutyric acid (AIB), frozen, and stored over liquid N2. After internal radiation had reduced survival to 1 in 10(4), survivors were plated and tested for their ability to transport AIB. Out of 200 clones te...

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

authors： Finkelstein MC,Slayman CW,Adelberg EA

更新日期：1977-10-01 00:00:00

abstract：:Variation in the masticatory behavior of hunter-gatherer and agricultural populations is hypothesized to be one of the major forces affecting the form of the human mandible. However, this has yet to be analyzed at a global level. Here, the relationship between global mandibular shape variation and subsistence economy ...

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

authors： von Cramon-Taubadel N

更新日期：2011-12-06 00:00:00

abstract：:Historically, the biodiversity and composition of species in a locality was thought to be influenced primarily by deterministic factors. In such cases, species' niches create differential responses to environmental conditions and interspecific interactions, which combine to determine that locality's biodiversity and s...

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

authors： Chase JM

更新日期：2007-10-30 00:00:00

abstract：:In the last 60,000 y humans have expanded across the globe and now occupy a wider range than any other terrestrial species. Our ability to successfully adapt to such a diverse range of habitats is often explained in terms of our cognitive ability. Humans have relatively bigger brains and more computing power than othe...

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

authors： Boyd R,Richerson PJ,Henrich J

更新日期：2011-06-28 00:00:00

abstract：:Many discoveries in cell biology rely on making specific proteins visible within their native cellular environment. There are various genetically encoded tags, such as fluorescent proteins, developed for fluorescence microscopy (FM). However, there are almost no genetically encoded tags that enable cellular proteins t...

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

authors： Doh JK,White JD,Zane HK,Chang YH,López CS,Enns CA,Beatty KE

更新日期：2018-12-18 00:00:00

abstract：:Oncogene-induced senescence (OIS) is an initial barrier to tumor development. Reactive oxygen species (ROS) is critical for oncogenic Ras OIS, but the downstream effectors to mediate ROS signaling are still relatively elusive. Senescent cells develop a senescence-associated secretory phenotype (SASP). However, the mec...

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

authors： Wang P,Han L,Shen H,Wang P,Lv C,Zhao G,Niu J,Xue L,Wang QJ,Tong T,Chen J

更新日期：2014-05-27 00:00:00

abstract：:Radiation leukemia virus, isolated from radiation-induced lymphomas in C57BL/Ka mice and propagated in that strain, is thymotropic and leukemogenic in vivo but replicates poorly, if at all, in mouse and mink fibroblast cultures in vitro. Comparative studies indicate that this naturally occurring virus is distinct from...

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

authors： Declève A,Lieberman M,Ihle JN,Kaplan HS

更新日期：1976-12-01 00:00:00

abstract：:The ion transport properties of the rough endoplasmic reticulum (RER) from liver have been defined by using measurements of active and potential gradient-driven transport. The Ca2+ pump is shown to be electrogenic, and both ATP and potential difference is able to drive vanadate-inhibitable Ca2+ uptake into the RER. AT...

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

authors： Muallem S,Schoeffield M,Pandol S,Sachs G

更新日期：1985-07-01 00:00:00

abstract：:α-Dystroglycan (α-DG) is a highly glycosylated basement membrane receptor that is cleaved by the proprotein convertase furin, which releases its N-terminal domain (α-DGN). Before cleavage, α-DGN interacts with the glycosyltransferase LARGE1 and initiates functional O-glycosylation of the mucin-like domain of α-DG. Not...

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

authors： de Greef JC,Slütter B,Anderson ME,Hamlyn R,O'Campo Landa R,McNutt EJ,Hara Y,Pewe LL,Venzke D,Matsumura K,Saito F,Harty JT,Campbell KP

更新日期：2019-06-04 00:00:00

abstract：:Protein tyrosine phosphorylation and dephosphorylation are key regulatory events in T-cell receptor (TCR) signaling. We investigated the role of the tyrosine phosphatase SHPTP1 in TCR signaling by analysis of TCR signal transduction in motheaten (me/me) mice, which lack SHPTP1 expression. As revealed by flow cytometri...

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

authors： Lorenz U,Ravichandran KS,Burakoff SJ,Neel BG

更新日期：1996-09-03 00:00:00

abstract：:Cytotoxic T lymphocytes (CTLs) recognize antigens in the context of major histocompatibility complex (MHC) class I gene products. The T-cell receptor (TCR) that mediates this MHC-restricted antigen recognition recognizes short peptide fragments rather than the intact antigen. Presentation of peptides to the TCR may th...

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

authors： Kievits F,Wijffels J,Lokhorst W,Ivanyi P

更新日期：1989-01-01 00:00:00

abstract：:We show in climate model experiments that large-scale afforestation in northern mid-latitudes warms the Northern Hemisphere and alters global circulation patterns. An expansion of dark forests increases the absorption of solar energy and increases surface temperature, particularly in regions where the land surface is ...

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

authors： Swann AL,Fung IY,Chiang JC

更新日期：2012-01-17 00:00:00

abstract：:Preference behaviors are often established during early life, but the underlying neural circuit mechanisms remain unknown. Adapting a unique nesting behavior assay, we confirmed a "critical period" for developing music preference in C57BL/6 mice. Early music exposure between postnatal days 15 and 24 reversed their inn...

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

authors： Yang EJ,Lin EW,Hensch TK

更新日期：2012-10-16 00:00:00