Plant richness, turnover, and evolutionary diversity track gradients of stability and ecological opportunity in a megadiversity center.

abstract：:The cellulose synthesizing terminal complex consisting of subunits A, B, C, and D in Acetobacter xylinum spans the outer and inner cell membranes to synthesize and extrude glucan chains, which are assembled into subelementary fibrils and further into a ribbon. We determined the structures of subunit D (AxCeSD/AxBcsD) ...

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

authors： Hu SQ,Gao YG,Tajima K,Sunagawa N,Zhou Y,Kawano S,Fujiwara T,Yoda T,Shimura D,Satoh Y,Munekata M,Tanaka I,Yao M

更新日期：2010-10-19 00:00:00

abstract：:China has experienced rapid urbanization and dramatic economic growth since its reform process started in late 1978. In this article, we present evidence for a significant urbanization effect on climate based on analysis of impacts of land-use changes on surface temperature in southeast China, where rapid urbanization...

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

authors： Zhou L,Dickinson RE,Tian Y,Fang J,Li Q,Kaufmann RK,Tucker CJ,Myneni RB

更新日期：2004-06-29 00:00:00

abstract：:We present a method for studying RNA processing and ribonucleoprotein assembly in vivo, by using RNA synthesized in vitro. SP6-transcribed 32P-labeled U2 small nuclear RNA precursor molecules were introduced into cultured human 293 cells by calcium phosphate-mediated uptake, as in standard DNA transfection experiments...

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

authors： Kleinschmidt AM,Pederson T

更新日期：1990-02-01 00:00:00

abstract：:We describe here a simple and easily manipulatable Escherichia coli-based genetic system that permits us to identify bacterial gene products that modulate the sensitivity of bacteria to tumoricidal agents, such as DMP 840, a bisnaphthalimide drug. To the extent that the action of these agents is conserved, these studi...

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

authors： Chatterjee PK,Sternberg NL

更新日期：1995-09-12 00:00:00

abstract：:To define the T-cell receptor signal transduction motif, we have transfected human and murine T-cell lines with a chimeric receptor consisting of the extracellular and transmembrane domains of human CD8 alpha and the membrane-proximal portion of CD3 zeta containing at its C terminus either an 18-amino acid segment (NQ...

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

authors： Koyasu S,Tse AG,Moingeon P,Hussey RE,Mildonian A,Hannisian J,Clayton LK,Reinherz EL

更新日期：1994-07-05 00:00:00

abstract：:Arginine methylation has emerged as a widespread and reversible protein modification with the potential to regulate a multitude of cellular processes, but its function is poorly understood. Endolysosomes play an important role in Wnt signaling, in which glycogen synthase kinase 3 (GSK3) becomes sequestered inside mult...

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

authors： Albrecht LV,Ploper D,Tejeda-Muñoz N,De Robertis EM

更新日期：2018-06-05 00:00:00

abstract：:The CD8 dimer interacts with the alpha 3 domain of major histocompatibility complex class I molecules through two immunoglobulin variable-like domains. In this study a crystal structure-informed mutational analysis has been performed to identify amino acids in the CD8 alpha/alpha homodimer that are likely to be involv...

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

authors： Giblin PA,Leahy DJ,Mennone J,Kavathas PB

更新日期：1994-03-01 00:00:00

abstract：:The ecological niche is a key concept for elucidating patterns of species distributions and developing strategies for conserving biodiversity. However, recent times are seeing a widespread debate whether species niches are conserved across space and time (niche conservatism hypothesis). Biological invasions represent ...

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

authors： Liu C,Wolter C,Xian W,Jeschke JM

更新日期：2020-09-22 00:00:00

abstract：:The high-pressure behavior of amorphous selenium has been investigated with time-resolved diamond anvil cell synchrotron x-ray diffraction and computed microtomography techniques. A two-step dynamic crystallization process is observed in which the monoclinic phase crystallized from the amorphous selenium and gradually...

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

authors： Liu H,Wang L,Xiao X,De Carlo F,Feng J,Mao HK,Hemley RJ

更新日期：2008-09-09 00:00:00

abstract：:The body-wall muscle cells of the nematode Caenorhabditis elegans produce thick filaments during embryonic, larval, and adult stages. These thick filaments contain two myosin isoforms, A and B, which assemble into different zones along the 10-microns lengths. Paramyosin, a protein homologous to myosin rods, forms a su...

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

authors： Honda S,Epstein HF

更新日期：1990-02-01 00:00:00

abstract：:When treated with heat-killed bacterial cells, mosquito cells in culture respond by up-regulating several proteins. Among these is a 66-kDa protein (p66) that is secreted from cells derived from both Aedes aegypti and Aedes albopictus. p66 was degraded by proteolysis and gave a virtually identical pattern of peptide p...

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

authors： Yoshiga T,Hernandez VP,Fallon AM,Law JH

更新日期：1997-11-11 00:00:00

abstract：:Despite their importance for biological activity, slower molecular motions beyond the nanosecond range remain poorly understood. We have assembled an unprecedented set of experimental NMR data, comprising up to 27 residual dipolar couplings per amino acid, to define the nature and amplitude of backbone motion in prote...

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

authors： Bouvignies G,Bernadó P,Meier S,Cho K,Grzesiek S,Brüschweiler R,Blackledge M

更新日期：2005-09-27 00:00:00

abstract：:We study the physical origins of phase contrast in dynamic atomic force microscopy (dAFM) in liquids where low-stiffness microcantilever probes are often used for nanoscale imaging of soft biological samples with gentle forces. Under these conditions, we show that the phase contrast derives primarily from a unique ene...

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

authors： Melcher J,Carrasco C,Xu X,Carrascosa JL,Gómez-Herrero J,José de Pablo P,Raman A

更新日期：2009-08-18 00:00:00

abstract：:AvrXa7 is a member of the avrBs3 avirulence gene family, which encodes proteins targeted to plant cells by a type III secretion apparatus. AvrXa7, the product of avrXa7, is also a virulence factor in strain PXO86 of Xanthomonas oryzae pv. oryzae. Avirulence and virulence specificities are associated with the central r...

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

authors： Yang B,Zhu W,Johnson LB,White FF

更新日期：2000-08-15 00:00:00

abstract：:Cofilin-actin rods are inclusion-like structures that are induced by certain chemical or physical stresses in cultured cells, and the rods formed in neurons are thought to be associated with neurodegeneration. Here, we cloned an Aplysia cofilin homolog and overexpressed it in cultured neurons. Overexpressed cofilin fo...

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

authors： Jang DH,Han JH,Lee SH,Lee YS,Park H,Lee SH,Kim H,Kaang BK

更新日期：2005-11-01 00:00:00

abstract：:Astrocyte-elevated gene-1 (AEG-1) expression is increased in multiple cancers and plays a central role in Ha-ras-mediated oncogenesis through the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Additionally, overexpression of AEG-1 protects primary and transformed human and rat cells from serum starvation-...

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

authors： Emdad L,Lee SG,Su ZZ,Jeon HY,Boukerche H,Sarkar D,Fisher PB

更新日期：2009-12-15 00:00:00

abstract：:The RNA virus, hepatitis E virus (HEV) is the most or second-most important cause of acute clinical hepatitis in adults throughout much of Asia, the Middle East, and Africa. In these regions it is an important cause of acute liver failure, especially in pregnant women who have a mortality rate of 20-30%. Until recentl...

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

authors： Shukla P,Nguyen HT,Torian U,Engle RE,Faulk K,Dalton HR,Bendall RP,Keane FE,Purcell RH,Emerson SU

更新日期：2011-02-08 00:00:00

abstract：:Glomeruli in the olfactory bulb are anatomically discrete modules receiving input from idiotypic olfactory sensory neurons. To examine the functional organization of sensory inputs to individual glomeruli, we loaded olfactory sensory neurons with a Ca(2+) indicator and measured odorant-evoked presynaptic Ca(2+) signal...

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

authors： Wachowiak M,Denk W,Friedrich RW

更新日期：2004-06-15 00:00:00

abstract：:The polymerization of individual RecA-DNA filaments, containing either single-stranded or double-stranded DNA, was followed in real time, and their mechanical properties were characterized with force-measuring laser tweezers. It was found that the stretch modulus of a filament is dominated by its (central) DNA compone...

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

authors： Hegner M,Smith SB,Bustamante C

更新日期：1999-08-31 00:00:00

abstract：:Escherichia coli O157:H7, a toxin-producing food and waterborne bacterial pathogen, has been linked to large outbreaks of gastrointestinal illness for more than two decades. E. coli O157 causes a wide range of clinical illness that varies by outbreak, although factors that contribute to variation in disease severity a...

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

authors： Manning SD,Motiwala AS,Springman AC,Qi W,Lacher DW,Ouellette LM,Mladonicky JM,Somsel P,Rudrik JT,Dietrich SE,Zhang W,Swaminathan B,Alland D,Whittam TS

更新日期：2008-03-25 00:00:00

abstract：:Several proteins have been identified that protect Drosophila telomeres from fusion events. They include UbcD1, HP1, HOAP, the components of the Mre11-Rad50-Nbs (MRN) complex, the ATM kinase, and the putative transcription factor Woc. Of these proteins, only HOAP has been shown to localize specifically at telomeres. H...

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

authors： Raffa GD,Siriaco G,Cugusi S,Ciapponi L,Cenci G,Wojcik E,Gatti M

更新日期：2009-02-17 00:00:00

abstract：:Transcription initiation is a dynamic process in which RNA polymerase (RNAP) and promoter DNA act as partners, changing in response to one another, to produce a polymerase/promoter open complex (RPo) competent for transcription. In Escherichia coli RNAP, region 1.1, the N-terminal 100 residues of sigma(70), is thought...

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

authors： Hook-Barnard IG,Hinton DM

更新日期：2009-01-20 00:00:00

abstract：:Deciphering the electron transfer reactivity characteristics of amyloid β-peptide copper complexes is an important task in connection with the role they are assumed to play in Alzheimer's disease. A systematic analysis of this question with the example of the amyloid β-peptide copper complex by means of its electroche...

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

authors： Balland V,Hureau C,Savéant JM

更新日期：2010-10-05 00:00:00

abstract：:The broad negative consequences of habitat degradation on biodiversity have been studied, but the complex effects of natural-agricultural landscape matrices remain poorly understood. Here we used stable carbon and nitrogen isotopes to detect changes in mammal resource and habitat use and trophic structure between pres...

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

authors： Magioli M,Moreira MZ,Fonseca RCB,Ribeiro MC,Rodrigues MG,Ferraz KMPMB

更新日期：2019-09-10 00:00:00

abstract：:Homopyrimidine oligonucleotides bind to the major groove of a complementary homopyrimidine.homopurine stretch by triple helix formation. The bla gene from transposon Tn3 contains a homopyrimidine.homopurine sequence of 13 base pairs located just downstream of the RNA polymerase binding site. A 13-mer homopyrimidine ol...

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

authors： Duval-Valentin G,Thuong NT,Hélène C

更新日期：1992-01-15 00:00:00

abstract：:On the basis of task-related imaging studies in normal human subjects, it has been suggested that two attention systems exist in the human brain: a bilateral dorsal attention system involved in top-down orienting of attention and a right-lateralized ventral attention system involved in reorienting attention in respons...

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

authors： Fox MD,Corbetta M,Snyder AZ,Vincent JL,Raichle ME

更新日期：2006-06-27 00:00:00

abstract：:We have shown recently that the temporal order of antioxidant consumption in human blood plasma exposed to a constant flux of aqueous peroxyl radicals is ascorbate = protein thiols greater than bilirubin greater than urate greater than alpha-tocopherol and that detectable lipid peroxidation starts only after ascorbate...

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

authors： Frei B,England L,Ames BN

更新日期：1989-08-01 00:00:00

abstract：:Of two closely related species of geese, one, the greylag goose, lives in the Indian plains all year round, while the other, the bar-headed goose, lives at the Tibetan lakes and migrates across the Himalayas to winter in India. Another species, the Andean goose, lives in the High Andes all year round. Possession of a ...

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

authors： Jessen TH,Weber RE,Fermi G,Tame J,Braunitzer G

更新日期：1991-08-01 00:00:00

abstract：:HD domain phosphohydrolase enzymes are characterized by a conserved set of histidine and aspartate residues that coordinate an active site metallocenter. Despite the important roles these enzymes play in nucleotide metabolism and signal transduction, few have been both biochemically and structurally characterized. Her...

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

authors： Bridwell-Rabb J,Kang G,Zhong A,Liu HW,Drennan CL

更新日期：2016-11-29 00:00:00

abstract：:The nonreceptor tyrosine phosphatase Shp2 (PTPN11) has been implicated in tyrosine kinase, cytokine, and integrin receptor signaling. We show here that conditional mutation of Shp2 in neural crest cells and in myelinating Schwann cells resulted in deficits in glial development that are remarkably similar to those obse...

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

authors： Grossmann KS,Wende H,Paul FE,Cheret C,Garratt AN,Zurborg S,Feinberg K,Besser D,Schulz H,Peles E,Selbach M,Birchmeier W,Birchmeier C

更新日期：2009-09-29 00:00:00