Diradical intermediate within the context of tryptophan tryptophylquinone biosynthesis.

abstract：:Blue mold of tobacco is caused by the fungus Peronospora tabacina. Its spores are released in the morning when the relative humidity falls, but they require free water for germination. Traditionally, the walls of the shade tents are raised to control the pathogen by drying leaves. We show that raising the walls does n...

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

authors： Aylor DE,Taylor GS

更新日期：1982-01-01 00:00:00

abstract：:Deficiency of acyl CoA:cholesterol acyltransferase 2 (ACAT2) in mice results in a reduction in cholesterol ester synthesis in the small intestine and liver, which in turn limits intestinal cholesterol absorption, hepatic cholesterol gallstone formation, and the accumulation of cholesterol esters in the plasma lipoprot...

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

authors： Willner EL,Tow B,Buhman KK,Wilson M,Sanan DA,Rudel LL,Farese RV Jr

更新日期：2003-02-04 00:00:00

abstract：:A serumless, chemically defined medium has been developed for the culture of oligodendrocytes isolated from primary neonatal rat cerebral cultures. Combined together, insulin, transferrin, and fibroblast growth factor synergistically induced an essentially homogenous population (95-98%) of cells expressing glycerol-3-...

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

authors： Saneto RP,de Vellis J

更新日期：1985-05-01 00:00:00

abstract：:Tregs are essential for maintaining peripheral tolerance, and thus targeting these cells may aid in the treatment of autoimmunity and cancer by enhancing or reducing suppressive functions, respectively. Before these cells can be harnessed for therapeutic purposes, it is necessary to understand how they maintain tolera...

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

authors： Pabbisetty SK,Rabacal W,Volanakis EJ,Parekh VV,Olivares-Villagómez D,Cendron D,Boyd KL,Van Kaer L,Sebzda E

更新日期：2016-08-09 00:00:00

abstract：:Somatostatin (somatotropin release-inhibiting factor; SRIF) is a tetradecapeptide present in brain, pancreas, gastrointestinal tract, and thyroid that inhibits the secretion or action of several hormones in these tissues. We observed that the toad urinary bladder contains concentrations of endogenous somatostatin (8.0...

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

authors： Forrest JN Jr,Reichlin S,Goodman DB

更新日期：1980-08-01 00:00:00

abstract：:The extracellular matrix (ECM) is an intricate network composed of an array of macromolecules capable of regulating the functional responsiveness of cells. Its composition greatly varies among different types of tissue, and dysregulation of its metabolism may contribute to vascular remodeling during the pathogenesis o...

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

authors： Roth M,Eickelberg O,Kohler E,Erne P,Block LH

更新日期：1996-05-28 00:00:00

abstract：:Hydrogen bond networks are key elements of protein structure and function but have been challenging to study within the complex protein environment. We have carried out in-depth interrogations of the proton transfer equilibrium within a hydrogen bond network formed to bound phenols in the active site of ketosteroid is...

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

authors： Sigala PA,Fafarman AT,Schwans JP,Fried SD,Fenn TD,Caaveiro JM,Pybus B,Ringe D,Petsko GA,Boxer SG,Herschlag D

更新日期：2013-07-09 00:00:00

abstract：:We report the complete sequence of an extreme halophile, Halobacterium sp. NRC-1, harboring a dynamic 2,571,010-bp genome containing 91 insertion sequences representing 12 families and organized into a large chromosome and 2 related minichromosomes. The Halobacterium NRC-1 genome codes for 2,630 predicted proteins, 36...

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

authors： Ng WV,Kennedy SP,Mahairas GG,Berquist B,Pan M,Shukla HD,Lasky SR,Baliga NS,Thorsson V,Sbrogna J,Swartzell S,Weir D,Hall J,Dahl TA,Welti R,Goo YA,Leithauser B,Keller K,Cruz R,Danson MJ,Hough DW,Maddocks DG,Jabl

更新日期：2000-10-24 00:00:00

abstract：:Cell adhesion molecules (CAMs) are cell surface glycoproteins that may play a variety of roles in morphogenesis and histogenesis, particularly in defining borders of discrete cell populations. To examine the influence of CAM expression on such cell segregation events in vitro, we have transfected cells with cDNAs codi...

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

authors： Friedlander DR,Mège RM,Cunningham BA,Edelman GM

更新日期：1989-09-01 00:00:00

abstract：:We have selected from a mixture of random polynucleotides an RNA that is able to replicate in the presence of the DNA-dependent RNA polymerase of Escherichia coli, provided the medium contains Mn(2+) and ITP, in addition to ATP, CTP, and UTP. The RNA consists of a chain of about 125 (+/-25) nucleotides and appears to ...

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

authors： Biebricher CK,Orgel LE

更新日期：1973-03-01 00:00:00

abstract：:The presynaptic plasma membrane protein SNAP-25 (synaptosome-associated protein of 25 kDa) has been implicated as one of several neural-specific components that direct constitutive fusion mechanisms to the regulated vesicle trafficking and exocytosis of neurotransmitter release. There exist two alternatively spliced i...

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

authors： Bark IC,Hahn KM,Ryabinin AE,Wilson MC

更新日期：1995-02-28 00:00:00

abstract：:Establishment, specification, and validation of synaptic connections are thought to be mediated by interactions between pre- and postsynaptic cell-adhesion molecules. Arguably, the best-characterized transsynaptic interactions are formed by presynaptic neurexins, which bind to diverse postsynaptic ligands. In a proteo...

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

authors： Sterky FH,Trotter JH,Lee SJ,Recktenwald CV,Du X,Zhou B,Zhou P,Schwenk J,Fakler B,Südhof TC

更新日期：2017-02-14 00:00:00

abstract：:The temporal and spatial patterns of floral determination in cultured internode segments of Nicotiana tabacum L. cv. Wisconsin 38 were investigated. Segments from internodes, when cultured on hormone-free medium, either produced some de novo floral shoots or produced only vegetative shoots. Segments that produced some...

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

authors： Singer SR,McDaniel CN

更新日期：1987-05-01 00:00:00

abstract：:Acetylcholine is the main neurotransmitter at the mammalian neuromuscular junction (NMJ) where nicotinic acetylcholine receptors mediate the signaling between nerve terminals and muscle fibers. We show that under glutamatergic transmission, rat NMJ switches from cholinergic type synapse to glutamatergic synapse. Conne...

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

authors： Brunelli G,Spano P,Barlati S,Guarneri B,Barbon A,Bresciani R,Pizzi M

更新日期：2005-06-14 00:00:00

abstract：:Cell-based therapies are attractive for revascularizing and regenerating tissues and organs, but clinical trials of endothelial progenitor cell transplantation have not resulted in consistent benefit. We propose a different approach in which a material delivery system is used to create a depot of vascular progenitor c...

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

authors： Silva EA,Kim ES,Kong HJ,Mooney DJ

更新日期：2008-09-23 00:00:00

abstract：:The coupling of calcium transport to ATP hydrolysis in rabbit muscle sarcoplasmic reticulum vesicles was determined under steady-state conditions in the presence of 5 mM oxalate and using various concentrations of vesicles to modulate the concentration of free Ca2+ in the medium. This experimental approach takes advan...

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

authors： Gafni A,Boyer PD

更新日期：1985-01-01 00:00:00

abstract：:Illumination of a system consisting of a vertical tube containing an unstirred homogeneous suspension of thylakoids in an imposed linear concentration gradient of an electron acceptor, 2,6-dichloroindophenol, gave rise to a one-dimensional banded pattern of the acceptor that evolved in a time-dependent manner. The spa...

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

authors： Aon M,Thomas D,Hervagault JF

更新日期：1989-01-01 00:00:00

abstract：:Whether the regulatory protein of an inducible operon for a catabolic pathway is a positive or a negative element in the control of expression is correlated with the frequent or infrequent presence, respectively, of the system's substrate in the natural environment. ...

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

authors： Savageau MA

更新日期：1974-06-01 00:00:00

abstract：:We have isolated a set of regulatory mutants defective in transcription termination at the attenuator in the leader region of the Escherichia coli tryptophan (trp) operon. In vivo the mutants have 2- to 4-fold increased levels of expression of the trp operon above the level of the trpR parental strain. These levels ar...

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

authors： Stauffer GV,Zurawski G,Yanofsky C

更新日期：1978-10-01 00:00:00

abstract：:The sequence of spontaneous Epstein-Barr virus activation was studied in P3HR-1 carrier cells and in P3HR-1(BrdU) cells made resistant to 5-bromodeoxyuridine. Virus activation was initiated during the normal cell cycle, and recruitment of additional virus-activated cells was prevented by the DNA inhibitors, 1-beta-D-a...

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

authors： Hampar B,Derge JG,Martos LM,Tagamets MA,Burroughs MA

更新日期：1972-09-01 00:00:00

abstract：:We describe here a third region of variability in human fibronectin (FN) due to alternative RNA splicing. Two other positions of alternative splicing have been reported previously (ED and IIICS). The third region involves a 273-nucleotide exon encoding exactly one 91-amino acid repeat of type III homology, located bet...

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

authors： Gutman A,Kornblihtt AR

更新日期：1987-10-01 00:00:00

abstract：:Genetic manipulation of the alpha(2A)-adrenergic receptor (alpha(2A)-AR) in mice has revealed the role of this subtype in numerous responses, including agonist-induced hypotension and sedation. Unexpectedly, alpha(2)-agonist treatment of mice heterozygous for the alpha(2A)-AR (alpha(2A)-AR(+/-)) lowers blood pressure ...

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

authors： Tan CM,Wilson MH,MacMillan LB,Kobilka BK,Limbird LE

更新日期：2002-09-17 00:00:00

abstract：:The apparatus of photosynthetic energy conversion in chloroplasts is quite well characterized with respect to structure and function. Light-driven electron transport in the thylakoid membrane is coupled to synthesis of ATP, used to drive energy-dependent metabolic processes in the stroma and the outer surface of the t...

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

authors： Spetea C,Hundal T,Lundin B,Heddad M,Adamska I,Andersson B

更新日期：2004-02-03 00:00:00

abstract：:There is now abundant evidence to substantiate an important role of hepatitis C virus (HCV) core protein in cellular gene expression as well as in the viral cycle. Thus the subcellular localization of this protein has important implications. However, several studies have shown controversial results: the HCV core has b...

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

authors： Barba G,Harper F,Harada T,Kohara M,Goulinet S,Matsuura Y,Eder G,Schaff Z,Chapman MJ,Miyamura T,Bréchot C

更新日期：1997-02-18 00:00:00

abstract：:Climate change is expected to cause shifts in the composition of tropical montane forests towards increased relative abundances of species whose ranges were previously centered at lower, hotter elevations. To investigate this process of "thermophilization," we analyzed patterns of compositional change over the last de...

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

authors： Duque A,Stevenson PR,Feeley KJ

更新日期：2015-08-25 00:00:00

abstract：:Although rigorous measures of similarity for sequence and structure are now well established, the problem of defining functional relationships has been particularly daunting. Here, we present several manifold embedding techniques to compute distances between Gene Ontology (GO) functional annotations and consequently e...

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

authors： Lerman G,Shakhnovich BE

更新日期：2007-07-03 00:00:00

abstract：:Autism spectrum disorder (ASD) is characterized by impaired social interactions and communication. The pathogenesis of ASD is not known, but it involves activation of microglia. We had shown that the peptide neurotensin (NT) is increased in the serum of children with ASD and stimulates cultured adult human microglia t...

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

authors： Tsilioni I,Pantazopoulos H,Conti P,Leeman SE,Theoharides TC

更新日期：2020-07-14 00:00:00

abstract：:In an 1885 paper, E. Picard defined a subgroup Tau(Lambda) of PU(2,1) generated by monodromies and depending on parameters Lambda = (lambda(1),lambda(2),lambda(3),lambda(4)), 0 < lambda(i) < 1, < lambda(i) < 3, lambda(i) + lambda(j) >/= 1, 1

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

authors： Mostow GD

更新日期：1981-10-01 00:00:00

abstract：:We show that the diverse ecoregions of Madagascar share one distinctive climatic feature: unpredictable intra- or interannual precipitation compared with other regions with comparable rainfall. Climatic unpredictability is associated with unpredictable patterns of fruiting and flowering. It is argued that these featur...

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

authors： Dewar RE,Richard AF

更新日期：2007-08-21 00:00:00

abstract：:Lon (or La) is a soluble, homooligomeric ATP-dependent protease. Mass determination and cryoelectron microscopy of pure mitochondrial Lon from Saccharomyces cerevisiae identify Lon as a flexible ring-shaped heptamer. In the presence of ATP or 5'-adenylylimidodiphosphate, most of the rings are symmetric and resemble ot...

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

authors： Stahlberg H,Kutejová E,Suda K,Wolpensinger B,Lustig A,Schatz G,Engel A,Suzuki CK

更新日期：1999-06-08 00:00:00