A cellular enhancer of retrovirus gene expression in embryonal carcinoma cells.

abstract：:The fluorescence decay functions of individual, specifically labeled tRNAPhe molecules exhibit nonexponential character as a result of conformational dynamics occurring during the measurement on a single molecule. tRNAPhe conformational states that interchange much more slowly are evidenced by the distribution of life...

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

authors： Jia Y,Sytnik A,Li L,Vladimirov S,Cooperman BS,Hochstrasser RM

更新日期：1997-07-22 00:00:00

abstract：:Membrane contact sites (MCSs) in eukaryotic cells are hotspots for lipid exchange, which is essential for many biological functions, including regulation of membrane properties and protein trafficking. Lipid transfer proteins anchored at membrane contact sites (LAMs) contain sterol-specific lipid transfer domains [StA...

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

authors： Tong J,Manik MK,Im YJ

更新日期：2018-01-30 00:00:00

abstract：:In the central nervous system, myelin proteolipid protein isoforms (PLP and DM20) play an essential structural role in myelination. It has been shown in several species that myelination is impaired by molecular defects resulting from single base mutations in the PLP gene. We have used DNA amplification by polymerase c...

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

authors： Pham-Dinh D,Popot JL,Boespflug-Tanguy O,Landrieu P,Deleuze JF,Boué J,Jollès P,Dautigny A

更新日期：1991-09-01 00:00:00

abstract：:The structural requirements of E. coli formylmethionine tRNA for aminoacylation have been examined by chemical modification of the tRNA, followed by separation of the modified molecules into active and inactive components. Photooxidation of tRNA(fMet) at 50 degrees in the presence of methylene blue results in modifica...

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

authors： Schulman LH

更新日期：1972-12-01 00:00:00

abstract：:The cat-86 gene in plasmid pPL603 specifies chloramphenicol acetyltransferase (CAT) and is selectively expressed in Bacillus subtilis at a stage in sporulation in which internal spores are first observed (approximately T8). The gene is unexpressed in vegetatively growing cells. cat-86 expression and spore formation ar...

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

authors： Mongkolsuk S,Lovett PS

更新日期：1984-06-01 00:00:00

abstract：:Hematin administered intravenously in a patient with congenital erythropoietic porphyria evidently entered erythrocyte precursors in the bone marrow, producing the well-known negative feedback repression of porphyrin biosynthesis with marked decline of porphyrin concentrations in urine, circulating plasma, and erythro...

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

authors： Watson CJ,Bossenmaier I,Cardinal R,Petryka ZJ

更新日期：1974-02-01 00:00:00

abstract：:Intron removal from tRNA precursors involves cleavage by a tRNA splicing endonuclease to yield tRNA 3'-halves beginning with a 5'-hydroxyl, and 5'-halves ending in a 2',3'-cyclic phosphate. A tRNA ligase then incorporates this phosphate into the internucleotide bond that joins the two halves. Although this 3'-P RNA sp...

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

authors： Englert M,Sheppard K,Aslanian A,Yates JR 3rd,Söll D

更新日期：2011-01-25 00:00:00

abstract：:More than a thousand proteins are thought to contribute to mammalian chromatin and its regulation, but our understanding of the genomic occupancy and function of most of these proteins is limited. Here we describe an approach, which we call "chromatin proteomic profiling," to identify proteins associated with genomic ...

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

authors： Ji X,Dadon DB,Abraham BJ,Lee TI,Jaenisch R,Bradner JE,Young RA

更新日期：2015-03-24 00:00:00

abstract：:The phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway was recently shown to negatively regulate LPS-induced acute inflammatory responses. We previously observed that the metabolic thiol antioxidant alpha-lipoic acid (LA) inhibits LPS-induced expression of cellular adhesion molecules and adheren...

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

authors： Zhang WJ,Wei H,Hagen T,Frei B

更新日期：2007-03-06 00:00:00

abstract：:Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of unknown cause that afflicts the central nervous system. MS is typified by a highly clonally restricted antigen-driven antibody response that is confined largely to the central nervous system. The major antigenic targets of this response and the...

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

authors： Williamson RA,Burgoon MP,Owens GP,Ghausi O,Leclerc E,Firme L,Carlson S,Corboy J,Parren PW,Sanna PP,Gilden DH,Burton DR

更新日期：2001-02-13 00:00:00

abstract：:The nucleotide sequences of eight origin-defective mutants of simian virus 40 have been determined. All of the mutants have suffered deletions, which range in size from 4 to 241 nucleotides. Some of the mutants induce the synthesis of tumor (T) antigen, others do not. Viral mRNA extracted from rat cells transformed by...

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

authors： Gluzman Y,Sambrook JF,Frisque RJ

更新日期：1980-07-01 00:00:00

abstract：:A monomorphic anti-HLA-G monoclonal antibody (mAb) was obtained by immunization of HLA-B27/human beta 2-microglobulin double-transgenic mice with transfected murine L cells expressing both HLA-G and human beta 2-microglobulin. This mAb, designated BFL.1, specifically recognizes, by flow cytometry analysis, the immuniz...

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

authors： Bensussan A,Mansur IG,Mallet V,Rodriguez AM,Girr M,Weiss EH,Brem G,Boumsell L,Gluckman E,Dausset J

更新日期：1995-10-24 00:00:00

abstract：:Export of LDL-derived cholesterol from lysosomes requires the cooperation of the integral membrane protein Niemann-Pick C1 (NPC1) and a soluble protein, Niemann-Pick C2 (NPC2). Mutations in the genes encoding these proteins lead to Niemann-Pick disease type C (NPC). NPC2 binds to NPC1's second (middle), lumenally orie...

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

authors： Li X,Saha P,Li J,Blobel G,Pfeffer SR

更新日期：2016-09-06 00:00:00

abstract：:A densely packed granular system is an example of an out-of-equilibrium system in the jammed state. It has been a longstanding problem to determine whether this class of systems can be described by concepts arising from equilibrium statistical mechanics, such as an effective temperature and compactivity. The measureme...

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

authors： Song C,Wang P,Makse HA

更新日期：2005-02-15 00:00:00

abstract：:The cellular models generally used in the in vitro evaluation of anti-human immunodeficiency virus compounds are dividing cells. A model constituted by resting lymphocytes may more accurately reflect a drug's future efficacy in humans, since viral DNA synthesis is known to take place in quiescent cells, creating a res...

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

authors： Malley SD,Grange JM,Hamedi-Sangsari F,Vila JR

更新日期：1994-11-08 00:00:00

abstract：:Mammalian nervous system function involves billions of neurons which are interconnected in a multitude of neural circuits. Here we describe a genetic approach to chart neural circuits. By using an olfactory-specific promoter, we selectively expressed barley lectin in sensory neurons in the olfactory epithelium and vom...

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

authors： Horowitz LF,Montmayeur JP,Echelard Y,Buck LB

更新日期：1999-03-16 00:00:00

abstract：:Vaccinia virus encodes a multisubunit DNA-dependent RNA polymerase (EC 2.7.7.6) that is packaged in the infectious virus particle. This polymerase was found to contain a submolar polypeptide of approximately 85 kDa in addition to the core subunits, which consist of two larger and several smaller polypeptides. The poly...

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

authors： Ahn BY,Moss B

更新日期：1992-04-15 00:00:00

abstract：:It is becoming clear that steroids can be synthesized de novo by the brain and other nervous systems. Such steroids are called neurosteroids, and de novo neurosteroidogenesis from cholesterol is a conserved property of vertebrate brains. In this study, we show that the newt brain actively produces 7alpha-hydroxypregne...

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

authors： Matsunaga M,Ukena K,Baulieu EE,Tsutsui K

更新日期：2004-12-07 00:00:00

abstract：:Acetyl-CoA carboxylase 1 (ACC1) catalyzes the formation of malonyl-CoA, the C2 donor for de novo synthesis of long-chain fatty acids. We have identified 64 exons, including 7 alternatively spliced minor exons (1A, 1B, 1C, 3, 5A', 5A, and 5B) in human ACC1 gene ( approximately 330 kb). The gene is regulated by three pr...

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

authors： Mao J,Chirala SS,Wakil SJ

更新日期：2003-06-24 00:00:00

abstract：:1-Aminocyclopropane-1-carboxylate (ACC) synthase (EC 4.4.1.14), extracted from tomato pericarp tissue, was purified 6500-fold by conventional and high-performance liquid chromatography. Two-dimensional gel electrophoresis of this preparation indicated that ACC synthase activity was associated with a protein band at 50...

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

authors： Bleecker AB,Kenyon WH,Somerville SC,Kende H

更新日期：1986-10-01 00:00:00

abstract：:Biotin plays an essential role in growth of mycobacteria. Synthesis of the cofactor is essential for Mycobacterium tuberculosis to establish and maintain chronic infections in a murine model of tuberculosis. Although the late steps of mycobacterial biotin synthesis, assembly of the heterocyclic rings, are thought to f...

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

authors： Hu Z,Cronan JE

更新日期：2020-09-22 00:00:00

abstract：:The proteolytic cleavage of sterol regulatory element-binding proteins (SREBPs) is regulated by SREBP cleavage-activating protein (SCAP), which forms complexes with SREBPs in membranes of the endoplasmic reticulum (ER). In sterol-depleted cells, SCAP facilitates cleavage of SREBPs by Site-1 protease, thereby initiatin...

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

authors： Nohturfft A,DeBose-Boyd RA,Scheek S,Goldstein JL,Brown MS

更新日期：1999-09-28 00:00:00

abstract：:Cytosine methylation at CpG dinucleotides contributes to the epigenetic maintenance of gene silencing. Dynamic reprogramming of DNA methylation patterns is believed to play a key role during development and differentiation in vertebrates. The mechanisms of DNA demethylation remain unclear and controversial. Here, we p...

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

authors： Kress C,Thomassin H,Grange T

更新日期：2006-07-25 00:00:00

abstract：:The genomic basis of primate phenotypic uniqueness remains obscure, despite increasing genome and transcriptome sequence data availability. Although factors such as segmental duplications and positive selection have received much attention as potential drivers of primate phenotypes, single-copy primate-specific genes ...

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

authors： Tay SK,Blythe J,Lipovich L

更新日期：2009-07-21 00:00:00

abstract：:The mechanism of proton transfer from the bulk into the membrane protein interior was studied. The light-induced reduction of a bound ubiquinone molecule Q(B) by the photosynthetic reaction center is accompanied by proton trapping. We used kinetic spectroscopy to measure (i) the electron transfer to Q(B) (at 450 nm), ...

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

authors： Gopta OA,Cherepanov DA,Junge W,Mulkidjanian AY

更新日期：1999-11-09 00:00:00

abstract：:In normal messenger RNA for the human beta-globin chain, nucleotide sequences have been identified which can be matched to the amino-acid sequence of the abnormally long segment of the beta-chain of hemoglobin Cranston. The finding of these sequences strengthens the hypothesis that the betaCranston chain arose by a fr...

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

authors： Forget BG,Marotta CA,Weissman SM,Cohen-Solal M

更新日期：1975-09-01 00:00:00

abstract：:The enhanced disease resistance 1 (edr1) mutation of Arabidopsis confers resistance to powdery mildew disease caused by the fungus Erysiphe cichoracearum. Resistance mediated by the edr1 mutation is correlated with induction of several defense responses, including host cell death. Double mutant analysis revealed that ...

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

authors： Frye CA,Tang D,Innes RW

更新日期：2001-01-02 00:00:00

abstract：:Determining trend and implementing detrending operations are important steps in data analysis. Yet there is no precise definition of "trend" nor any logical algorithm for extracting it. As a result, various ad hoc extrinsic methods have been used to determine trend and to facilitate a detrending operation. In this art...

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

authors： Wu Z,Huang NE,Long SR,Peng CK

更新日期：2007-09-18 00:00:00

abstract：:Tubular membrane structures are widespread in eukaryotic cells, but the mechanisms underlying their formation and stability are not well understood. Previous work has focused on tube extrusion from cells and model membranes under the application of external forces. Here, we present novel membrane/polymer systems, wher...

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

authors： Li Y,Lipowsky R,Dimova R

更新日期：2011-03-22 00:00:00

abstract：:Initiation of X chromosome inactivation requires the presence, in cis, of the X inactivation center (XIC). The Xist gene, which lies within the XIC region in both human and mouse and has the unique property of being expressed only from the inactive X chromosome in female somatic cells, is known to be essential for X i...

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

authors： Heard E,Mongelard F,Arnaud D,Chureau C,Vourc'h C,Avner P

更新日期：1999-06-08 00:00:00