Geological sulfur isotopes indicate elevated OCS in the Archean atmosphere, solving faint young sun paradox.

abstract：:Photoadaptation, the ability to attenuate a light response on prolonged light exposure while remaining sensitive to escalating changes in light intensity, is essential for organisms to decipher time information appropriately, yet the underlying molecular mechanisms are poorly understood. In Neurospora crassa, VIVID (V...

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

authors： Chen CH,DeMay BS,Gladfelter AS,Dunlap JC,Loros JJ

更新日期：2010-09-21 00:00:00

abstract：:We have used electron microscopy to examine freshly isolated Salmonella typhimurium and Escherichia coli basal flagellar fragments, purified without resort to extremes of pH or ionic strength. Such fragments contain the large bell-like basal structures visualized recently in freeze-substituted or fixed preparations. W...

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

authors： Khan IH,Reese TS,Khan S

更新日期：1992-07-01 00:00:00

abstract：:DNA photolyase is a pyrimidine-dimer repair enzyme that uses visible light. Photolyase generally contains two chromophore cofactors. One is a catalytic cofactor directly contributing to the repair of a pyrimidine-dimer. The other is a light-harvesting cofactor, which absorbs visible light and transfers energy to the c...

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

authors： Komori H,Masui R,Kuramitsu S,Yokoyama S,Shibata T,Inoue Y,Miki K

更新日期：2001-11-20 00:00:00

abstract：:Selection is usually considered to be the dominant force controlling viral variation; the large population sizes suggest that deterministic population genetic models are appropriate. To investigate their validity for HIV, samples of env gene sequences were tested for departure from neutrality because of mutation-selec...

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

authors： Brown AJ

更新日期：1997-03-04 00:00:00

abstract：:Despite the prevalence of transposable elements in the genomes of higher eukaryotes, what is virtually unknown is how they amplify to very high copy numbers without killing their host. Here, we report the discovery of rice strains where a miniature inverted-repeat transposable element (mPing) has amplified from approx...

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

authors： Naito K,Cho E,Yang G,Campbell MA,Yano K,Okumoto Y,Tanisaka T,Wessler SR

更新日期：2006-11-21 00:00:00

abstract：:Mouse beta-globin in encoded in a discontinuous structural gene interrupted by a 550-base pair intervening sequence of DNA. Correspondingly, the mature beta-globin mRNA appears to be synthesized via a 15S precursor, the length of which roughly equals the total length of the coding and intervening sequences of the beta...

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

authors： Tilghman SM,Curtis PJ,Tiemeier DC,Leder P,Weissmann C

更新日期：1978-03-01 00:00:00

abstract：:Previous studies have suggested that most papillomaviruses enter the host cell via clathrin-dependent receptor-mediated endocytosis but have not addressed later steps in viral entry. To examine these events, we followed the localization of L2 and packaged DNA after entry of infectious virions or L1/L2 pseudovirions. C...

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

authors： Day PM,Baker CC,Lowy DR,Schiller JT

更新日期：2004-09-28 00:00:00

abstract：:The substitution pattern of anthocyanin pigments is a main determinant of flower color. Flavonoid 3',5'-hydroxylase (F3'5'H) is a cytochrome P450 enzyme (Cyt P450) that catalyzes the 3', 5'-hydroxylation of dihydroflavonols, the precursors of purple anthocyanins. Species such as rose and carnation lack F3'5'H activity...

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

authors： de Vetten N,ter Horst J,van Schaik HP,de Boer A,Mol J,Koes R

更新日期：1999-01-19 00:00:00

abstract：:The eukaryote endomembrane system contains a class of H(+)-pumping ATPase (H(+)-ATPases) of the vacuolar type (V-ATPases) that are responsible for the acidification of organelles. Their action is critical to numerous physiological processes, but the regulatory mechanisms that may control activity are not yet fully und...

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

authors： Davies JM,Hunt I,Sanders D

更新日期：1994-08-30 00:00:00

abstract：:Biological soil crusts (biocrusts)—communities of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface—are fundamental components of drylands worldwide, and destruction of biocrusts dramatically alters biogeochemical processes, hydrology, surface energy balance, and vegetation cover. Although th...

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

authors： Ferrenberg S,Reed SC,Belnap J

更新日期：2015-09-29 00:00:00

abstract：:"Functional connectivity" techniques are commonplace tools for studying brain organization. A critical element of these analyses is to distinguish variance due to neurobiological signals from variance due to nonneurobiological signals. Multiecho fMRI techniques are a promising means for making such distinctions based ...

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

authors： Power JD,Plitt M,Gotts SJ,Kundu P,Voon V,Bandettini PA,Martin A

更新日期：2018-02-27 00:00:00

abstract：:The bifunctional Neurospora crassa mitochondrial tyrosyl-tRNA synthetase (CYT-18 protein) both aminoacylates mitochondrial tRNA(Tyr) and acts as a structure-stabilizing splicing cofactor for group I introns. Previous studies showed that CYT-18 has distinct tRNA(Tyr) and group I intron-binding sites, with the latter fo...

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

authors： Paukstelis PJ,Lambowitz AM

更新日期：2008-04-22 00:00:00

abstract：:The central administration of the fatty acid synthase (FAS) inhibitor, C75, rapidly suppresses the expression of orexigenic neuropeptides [neuropeptide Y (NPY) and agouti-related protein (AgRP)] and activates expression of anorexigenic neuropeptides [proopiomelanocortin (POMC) and cocaine- and amphetamine-regulated tr...

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

authors： Hu Z,Cha SH,van Haasteren G,Wang J,Lane MD

更新日期：2005-03-15 00:00:00

abstract：:Polyadenylylated RNA synthesized after heat shock was isolated from polysomes of cultured cells of Drosophila melanogaster and used as template to prepare cDNA. An excess of poly(A)-RNA from heat-shocked cells hybridized to 80% of the cDNA, whereas cytoplasmic poly(A)-RNA from cells grown at 25 degrees could drive onl...

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

authors： Biessmann H,Levy B,McCarthy BJ

更新日期：1978-02-01 00:00:00

abstract：:The use of profiling by ethnicity or nationality to trigger secondary security screening is a controversial social and political issue. Overlooked is the question of whether such actuarial methods are in fact mathematically justified, even under the most idealized assumptions of completely accurate prior probabilities...

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

authors： Press WH

更新日期：2009-02-10 00:00:00

abstract：:We established a pancreatic adenocarcinoma cell line (CFPAC-1) from a patient with cystic fibrosis (CF) and assessed some of its properties. The cells show epithelial morphology and express cytokeratin and oncofetal antigens characteristic of pancreatic duct cells. Basal and stimulated levels of cAMP and cAMP-dependen...

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

authors： Schoumacher RA,Ram J,Iannuzzi MC,Bradbury NA,Wallace RW,Hon CT,Kelly DR,Schmid SM,Gelder FB,Rado TA

更新日期：1990-05-01 00:00:00

abstract：:Nonribosomal peptides and polyketides are a diverse group of natural products with complex chemical structures and enormous pharmaceutical potential. They are synthesized on modular nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) enzyme complexes by a conserved thiotemplate mechanism. Here, we rep...

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

authors： Wang H,Fewer DP,Holm L,Rouhiainen L,Sivonen K

更新日期：2014-06-24 00:00:00

abstract：:The dendritic building blocks with a focal pyrene unit self-organize into vesicles in aqueous phase. The in situ inclusion of the focal pyrene units into the cavity of beta- or gamma-cyclodextrin (CD) induces self-assembled organic nanotubes with an average outer diameter of approximately 45 nm and inner diameter of 2...

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

authors： Park C,Lee IH,Lee S,Song Y,Rhue M,Kim C

更新日期：2006-01-31 00:00:00

abstract：:Previous studies have shown that the immunosuppressive and carcinogenic polycyclic aromatic hydrocarbon 7,12-dimethylbenz(a)anthracene (DMBA) impairs Ca(2+)-dependent transmembrane signaling in human and murine lymphocytes. The purpose of the present studies was to analyze potential mechanisms of immunosuppression by ...

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

authors： Archuleta MM,Schieven GL,Ledbetter JA,Deanin GG,Burchiel SW

更新日期：1993-07-01 00:00:00

abstract：:Soluble extracts of adenovirus-infected HeLa cell nuclei support DNA replication on exogenous adenovirus DNA templates. Conditions of synthesis using both wild-type and temperature-sensitive extracts have been defined. Nuclear extracts prepared from cells permissively infected with the adenovirus mutant H5ts125 expres...

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

authors： Kaplan LM,Ariga H,Hurwitz J,Horwitz MS

更新日期：1979-11-01 00:00:00

abstract：:How does genome evolution affect the rate of diversification of biological lineages? Recent studies have suggested that the overall rate of genome evolution is correlated with the rate of diversification. If true, this claim has important consequences for understanding the process of diversification, and implications ...

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

authors： Lanfear R,Ho SY,Love D,Bromham L

更新日期：2010-11-23 00:00:00

abstract：:Understanding the heritability of neural systems linked to psychopathology is not sufficient to implicate them as intergenerational neural mediators. By closely examining how individual differences in neural phenotypes and psychopathology cosegregate as they fall through the family tree, we can identify the brain syst...

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

authors： Fox AS,Oler JA,Shackman AJ,Shelton SE,Raveendran M,McKay DR,Converse AK,Alexander A,Davidson RJ,Blangero J,Rogers J,Kalin NH

更新日期：2015-07-21 00:00:00

abstract：:By using a systematic genetic approach, the resonances in the 19F NMR spectrum of 3-fluorotyrosine-substituted lac repressor protein have been assigned. The NMR data indicate that each monomer of the repressor consists of two distinct and independent domains. One domain, the NH2-terminal sixth of the primary sequence,...

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

authors： Jarema MA,Lu P,Miller JH

更新日期：1981-05-01 00:00:00

abstract：:Turkey erythrocyte membranes showed specific binding of [(3)H]epinephrine. The concentration of hormone required for half-maximal binding (30 muM) was the same as that required for half-maximal activation of the adenylate cyclase located in the same membrane preparation. The binding reaction at 37 degrees C reached co...

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

authors： Schramm M,Feinstein H,Naim E,Lang E,Lasser M

更新日期：1972-02-01 00:00:00

abstract：:In a medium without Na+, gamma-aminobutyric acid (GABA) binds at 0 degrees to freshly prepared crude synaptic membranes from rat cerebral cortex with an apparent dissociation constant of 218 nM. An endogenous inhibitor of the Na+-independent GABA binding was removed from these membranes by freezing and thawing and by ...

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

authors： Toffano G,Guidotti A,Costa E

更新日期：1978-08-01 00:00:00

abstract：:Pharmacological treatments designed to reactivate fetal γ-globin can lead to an effective and successful clinical outcome in patients with hemoglobinopathies. However, new approaches remain highly desired because such treatments are not equally effective for all patients, and toxicity issues remain. We have taken a sy...

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

authors： Chen J,Peterson KR,Iancu-Rubin C,Bieker JJ

更新日期：2010-09-28 00:00:00

abstract：:For 2 < k [abstract: see text] we define lifts of cuspidal Poincaré series in S(k)(Gamma(0)(N)) to weight 2 - k harmonic weak Maass forms. This construction answers a question of Dyson by providing the general framework "explaining" Ramanujan's mock theta functions. As an application, we show that the number of partit...

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

authors： Bringmann K,Ono K

更新日期：2007-03-06 00:00:00

abstract：:Epilepsy is the most common neurological disorder of young humans. Each year 150,000 children in the United States experience their first seizure. Antiepileptic drugs (AEDs), used to treat seizures in children, infants, and pregnant women, cause cognitive impairment, microcephaly, and birth defects. The cause of unwan...

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

authors： Bittigau P,Sifringer M,Genz K,Reith E,Pospischil D,Govindarajalu S,Dzietko M,Pesditschek S,Mai I,Dikranian K,Olney JW,Ikonomidou C

更新日期：2002-11-12 00:00:00

abstract：:DNA delivery of IL-12 has shown promise in reducing the toxic side effects associated with administration of recombinant human (h)IL-12 protein while maintaining the ability to inhibit tumor growth and abolish tumor metastases in animal models. We have developed a more potent version of IL-12 by using DNA shuffling an...

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

authors： Leong SR,Chang JC,Ong R,Dawes G,Stemmer WP,Punnonen J

更新日期：2003-02-04 00:00:00

abstract：:Biologically active (125)I-labeled bovine parathyroid hormone (prepared by electrolytic iodination) and its synthetic NH(2)-terminal (1-34) biologically active fragment bound rapidly and specifically to a purified plasma membrane preparation from bovine renal cortex. Binding of labeled intact hormone or labeled NH(2)-...

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

authors： Di Bella FP,Dousa TP,Miller SS,Arnaud CD

更新日期：1974-03-01 00:00:00