Structure of bacterial cellulose synthase subunit D octamer with four inner passageways.

abstract：:Alzheimer's disease (AD) is characterized by a progressive dysfunction of central neurons. Recent experimental evidence indicates that in the cortex, in addition to the silencing of a fraction of neurons, other neurons are hyperactive in amyloid-β (Aβ) plaque-enriched regions. However, it has remained unknown what com...

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

authors： Busche MA,Chen X,Henning HA,Reichwald J,Staufenbiel M,Sakmann B,Konnerth A

更新日期：2012-05-29 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：:We introduce and analyze a general model of a population evolving over a network of selectively neutral genotypes. We show that the population's limit distribution on the neutral network is solely determined by the network topology and given by the principal eigenvector of the network's adjacency matrix. Moreover, the...

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

authors： van Nimwegen E,Crutchfield JP,Huynen M

更新日期：1999-08-17 00:00:00

abstract：:Attention allows animals to respond selectively to competing stimuli, enabling some stimuli to evoke a behavioral response while others are ignored. How the brain does this remains mysterious, although it is increasingly evident that even animals with the smallest brains display this capacity. For example, insects res...

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

authors： Paulk AC,Stacey JA,Pearson TW,Taylor GJ,Moore RJ,Srinivasan MV,van Swinderen B

更新日期：2014-04-01 00:00:00

abstract：:A total of 289,868 locus tests, based on 28 different protein phenotypes and using one-dimensional electrophoresis to detect variant proteins, has yielded one probable mutation in the offspring of "proximally exposed" parents, who received an estimated average gonadal exposure of 31 to 39 rem in the atomic bombings of...

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

authors： Neel JV,Satoh C,Hamilton HB,Otake M,Goriki K,Kageoka T,Fujita M,Neriishi S,Asakawa J

更新日期：1980-07-01 00:00:00

abstract：:Prions are mammalian proteins (PrPs) with a unique pathogenic property: a nonendogenous isoform PrP(Sc) can catalyze conversion of the endogenous PrP(C) isoform into additional PrP(Sc). In this work, we demonstrate that PrP(C) helix 1 has certain properties (hydrophilicity, charge distribution) that make it unique amo...

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

authors： Morrissey MP,Shakhnovich EI

更新日期：1999-09-28 00:00:00

abstract：:Phosphorylation of the regulatory (R) domain initiates cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel activity. To discover how the function of this domain is determined by its structure, we produced an R domain protein (R8) that spanned residues 708-831 of CFTR. Phosphorylated, but not unpho...

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

authors： Ostedgaard LS,Baldursson O,Vermeer DW,Welsh MJ,Robertson AD

更新日期：2000-05-09 00:00:00

abstract：:Flowering time (i.e., heading date in crops) is an important ecological trait that determines growing seasons and regional adaptability of plants to specific natural environments. Rice (Oryza sativa L.) is a short-day plant that originated in the tropics. Increasing evidence suggests that the northward expansion of cu...

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

authors： Wu W,Zheng XM,Lu G,Zhong Z,Gao H,Chen L,Wu C,Wang HJ,Wang Q,Zhou K,Wang JL,Wu F,Zhang X,Guo X,Cheng Z,Lei C,Lin Q,Jiang L,Wang H,Ge S,Wan J

更新日期：2013-02-19 00:00:00

abstract：:Food is a powerful entrainment cue for circadian clocks in peripheral tissues, and changes in the composition of nutrients have been demonstrated to metabolically reprogram peripheral clocks. However, how food challenges may influence circadian metabolism of the master clock in the suprachiasmatic nucleus (SCN) or in ...

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

authors： Tognini P,Samad M,Kinouchi K,Liu Y,Helbling JC,Moisan MP,Eckel-Mahan KL,Baldi P,Sassone-Corsi P

更新日期：2020-11-24 00:00:00

abstract：:The helical ribosome structures of Mycoplasma gallisepticum have been analyzed by optical diffraction and the rotational symmetry technique. The helix repeat (510 A) is composed of 10 ribosomes in 3 turns. The rotational studies show some ribosome fine structure. ...

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

authors： Maniloff J

更新日期：1971-01-01 00:00:00

abstract：:RNAs 1 and 2 of the tripartite cowpea chlorotic mottle virus (CCMV) genome are sufficient for RNA replication in protoplasts, whereas systemic infection of cowpea plants additionally requires RNA3, which encodes the 3a noncapsid protein and coat protein. By using biologically active CCMV cDNA clones, we find that dele...

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

authors： Allison R,Thompson C,Ahlquist P

更新日期：1990-03-01 00:00:00

abstract：:Myelin basic proteins (MBP) are major constituents of the myelin sheath of oligodendrocytes and Schwann cells in the central nervous system and the peripheral nervous system, respectively. We previously showed that MBP-related transcripts are present in the bone marrow and the immune system. These mRNAs are transcribe...

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

authors： Marty MC,Alliot F,Rutin J,Fritz R,Trisler D,Pessac B

更新日期：2002-06-25 00:00:00

abstract：:In this contribution, we consider the advancement of ultrafast electron diffraction and microscopy to cover the attosecond time domain. The concept is centered on the compression of femtosecond electron packets to trains of 15-attosecond pulses by the use of the ponderomotive force in synthesized gratings of optical f...

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

authors： Baum P,Zewail AH

更新日期：2007-11-20 00:00:00

abstract：:Graphene oxide (GO), the main precursor of graphene-based materials made by solution processing, is known to be very stiff. Indeed, it has a Young's modulus comparable to steel, on the order of 300 GPa. Despite its very high stiffness, we show here that GO is superflexible. We quantitatively measure the GO bending rig...

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

authors： Poulin P,Jalili R,Neri W,Nallet F,Divoux T,Colin A,Aboutalebi SH,Wallace G,Zakri C

更新日期：2016-10-04 00:00:00

abstract：:A complementary DNA (cDNA) clone from a human placenta cDNA library encoding extracellular superoxide dismutase (EC-SOD; superoxide:superoxide oxidoreductase, EC 1.15.1.1) has been isolated and the nucleotide sequence determined. The cDNA has a very high G+C content. EC-SOD is synthesized with a putative 18-amino acid...

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

authors： Hjalmarsson K,Marklund SL,Engström A,Edlund T

更新日期：1987-09-01 00:00:00

abstract：:Cyclic AMP levels increase abruptly in the secondary palatal shelf (mesenchyme plus a two- to three-cell-layered epithelium) between day 15 and 16 of gestation in the rat embryo. The addition of dibutyryl cyclic AMP to the media in which immature palatal shelves (day 14) are cultured causes a precocious decrease in DN...

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

authors： Pratt RM,Martin GR

更新日期：1975-03-01 00:00:00

abstract：:Biomass burning drives changes in greenhouse gases, climate-forcing aerosols, and global atmospheric chemistry. There is controversy about the magnitude and timing of changes in biomass burning emissions on millennial time scales from preindustrial to present and about the relative importance of climate change and hum...

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

authors： Nicewonger MR,Aydin M,Prather MJ,Saltzman ES

更新日期：2018-12-04 00:00:00

abstract：:The role of RNA silencing as an antiviral defense mechanism in fungi was examined by testing the effect of dicer gene disruptions on mycovirus infection of the chestnut blight fungus Cryphonectria parasitica. C. parasitica dicer-like genes dcl-1 and dcl-2 were cloned and shown to share a high level of predicted amino ...

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

authors： Segers GC,Zhang X,Deng F,Sun Q,Nuss DL

更新日期：2007-07-31 00:00:00

abstract：:Overexpression of the p53 protein, resulting from gene mutations that increase protein stability, has been detected in greater than 25% of primary human breast cancers. In addition, approximately 10% of breast cancer patients have circulating antibodies to the p53 protein. In this study, the anti-p53 humoral response ...

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

authors： Davidoff AM,Iglehart JD,Marks JR

更新日期：1992-04-15 00:00:00

abstract：:Both plants and animals require the activity of proteins containing nucleotide binding (NB) domain and leucine-rich repeat (LRR) domains for proper immune system function. NB-LRR proteins in plants (NLR proteins in animals) also require conserved regulation via the proteins SGT1 and cytosolic HSP90. RAR1, a protein sp...

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

authors： Hubert DA,He Y,McNulty BC,Tornero P,Dangl JL

更新日期：2009-06-16 00:00:00

abstract：:Dehydroepiandrosterone (DHEA) is a neurosteroid with potential effects on neurogenesis and neuronal survival in humans. However, most studies on DHEA have been performed in rodents, and there is little direct evidence for biological effects on the human nervous system. Furthermore, the mechanism of its action is unkno...

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

authors： Suzuki M,Wright LS,Marwah P,Lardy HA,Svendsen CN

更新日期：2004-03-02 00:00:00

abstract：:Plants and animals deploy intracellular immune receptors that perceive specific pathogen effector proteins and microbial products delivered into the host cell. We demonstrate that the ADR1 family of Arabidopsis nucleotide-binding leucine-rich repeat (NB-LRR) receptors regulates accumulation of the defense hormone sali...

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

authors： Bonardi V,Tang S,Stallmann A,Roberts M,Cherkis K,Dangl JL

更新日期：2011-09-27 00:00:00

abstract：:Controversy remains over whether the cancer stem cell (CSC) theory applies to all tumors. To determine whether cells within a highly aggressive solid tumor are stochastically or hierarchically organized, we combined a reporter system where the nucleostemin (NS) promoter drives GFP expression (termed NS-GFP) with a mou...

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

authors： Tamase A,Muraguchi T,Naka K,Tanaka S,Kinoshita M,Hoshii T,Ohmura M,Shugo H,Ooshio T,Nakada M,Sawamoto K,Onodera M,Matsumoto K,Oshima M,Asano M,Saya H,Okano H,Suda T,Hamada J,Hirao A

更新日期：2009-10-06 00:00:00

abstract：:The method presented here refines molecular conformations directly against projections of single particles measured by electron microscopy. By optimizing the orientation of the projection at the same time as the conformation, the method is well-suited to two-dimensional class averages from cryoelectron microscopy. Suc...

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

authors： Zhang J,Minary P,Levitt M

更新日期：2012-06-19 00:00:00

abstract：:The proteasome regulates cellular processes as diverse as cell cycle progression and NF-kappaB activation. In this study, we show that the potent antitumor natural product epoxomicin specifically targets the proteasome. Utilizing biotinylated-epoxomicin as a molecular probe, we demonstrate that epoxomicin covalently b...

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

authors： Meng L,Mohan R,Kwok BH,Elofsson M,Sin N,Crews CM

更新日期：1999-08-31 00:00:00

abstract：:Physical activity increases energy metabolism in exercising muscle. Whether acute exercise elicits metabolic changes in nonexercising muscles remains unclear. We show that one of the few genes that is more highly induced in nonexercising muscle than in exercising human muscle during acute exercise encodes angiopoietin...

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

authors： Catoire M,Alex S,Paraskevopulos N,Mattijssen F,Evers-van Gogh I,Schaart G,Jeppesen J,Kneppers A,Mensink M,Voshol PJ,Olivecrona G,Tan NS,Hesselink MK,Berbée JF,Rensen PC,Kalkhoven E,Schrauwen P,Kersten S

更新日期：2014-03-18 00:00:00

abstract：:Activation of the CB2 receptor is apparently an endogenous protective mechanism. Thus, it restrains inflammation and protects the skeleton against age-related bone loss. However, the endogenous cannabinoids, as well as Δ(9)-tetrahydrocannabinol, the main plant psychoactive constituent, activate both cannabinoid recept...

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

authors： Smoum R,Baraghithy S,Chourasia M,Breuer A,Mussai N,Attar-Namdar M,Kogan NM,Raphael B,Bolognini D,Cascio MG,Marini P,Pertwee RG,Shurki A,Mechoulam R,Bab I

更新日期：2015-07-14 00:00:00

abstract：:Cooperation via production of common goods is found in diverse life forms ranging from viruses to social animals. However, natural selection predicts a "tragedy of the commons": Cheaters, benefiting from without producing costly common goods, are more fit than cooperators and should destroy cooperation. In an attempt ...

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

authors： Waite AJ,Shou W

更新日期：2012-11-20 00:00:00

abstract：:MuB is an ATP-dependent nonspecific DNA-binding protein that regulates the activity of the MuA transposase and captures target DNA for transposition. Mechanistic understanding of MuB function has previously been hindered by MuB's poor solubility. Here we combine bioinformatic, mutagenic, biochemical, and electron micr...

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

authors： Mizuno N,Dramićanin M,Mizuuchi M,Adam J,Wang Y,Han YW,Yang W,Steven AC,Mizuuchi K,Ramón-Maiques S

更新日期：2013-07-02 00:00:00

abstract：:Rabbit articular chondrocytes synthesize type II collagen [3alpha(1)(II)] in vivo and type I collagen [2alpha(1)(I).alpha(2)] in monolayer cultures. In suspension culture the nature of phenotype depends on extracellular Ca(2+). The relationship of Ca(2+) and 3':5'-cyclic AMP (cAMP) in regulation of collagen synthesis ...

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

authors： Deshmukh K,Sawyer BD

更新日期：1977-09-01 00:00:00