Codon specificity of UGA suppressor tRNATrp from Escherichia coli.

abstract：:The properties of a recently synthesized photolabile chelator for divalent cations are described, the affinity of which for Ca2+ changes by some 5 orders of magnitude on illumination. The compound 1-(2-nitro-4,5-dimethoxyphenyl)-N,N,N',N'-tetrakis[(oxycarbonyl)me thyl]-1,2-ethanediamine (DM-nitrophen) binds Ca2+ (Kd a...

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

authors： Kaplan JH,Ellis-Davies GC

更新日期：1988-09-01 00:00:00

abstract：:IDIOTYPY HAS BEEN STUDIED IN ANTIBODIES AGAINST A PROTEIN ANTIGEN: hen ovalbumin. Various fractions of antisera to hen ovalbumin have been compared from the standpoint of the idiotypic specificities found on the immunoglobulins that they contain. Idiotypic specificities were found to be common to (a) antibodies that w...

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

authors： Oudin J,Cazenave PA

更新日期：1971-10-01 00:00:00

abstract：:Exosomes have been proposed as vehicles for microRNA (miRNA) -based intercellular communication and a source of miRNA biomarkers in bodily fluids. Although exosome preparations contain miRNAs, a quantitative analysis of their abundance and stoichiometry is lacking. In the course of studying cancer-associated extracell...

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

authors： Chevillet JR,Kang Q,Ruf IK,Briggs HA,Vojtech LN,Hughes SM,Cheng HH,Arroyo JD,Meredith EK,Gallichotte EN,Pogosova-Agadjanyan EL,Morrissey C,Stirewalt DL,Hladik F,Yu EY,Higano CS,Tewari M

更新日期：2014-10-14 00:00:00

abstract：:Within the scientific community, much attention has focused on improving communications between scientists, policy makers, and the public. To date, efforts have centered on improving the content, accessibility, and delivery of scientific communications. Here we argue that in the current political and media environment...

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

authors： Iyengar S,Massey DS

更新日期：2019-04-16 00:00:00

abstract：:Endothelial cell growth factor (ECGF) binds specifically in vitro to membrane receptors present on the surface of several cell types, including murine and human endothelial cells and fibroblasts. Monoclonal antibodies prepared against ECGF that inhibit the mitogenic activity of the growth factor prevent receptor occup...

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

authors： Schreiber AB,Kenney J,Kowalski WJ,Friesel R,Mehlman T,Maciag T

更新日期：1985-09-01 00:00:00

abstract：:Nonribosomal peptide synthetases (NRPSs) usually catalyze the biosynthesis of peptide natural products by sequential selection, activation, and condensation of amino acid precursors. It was reported that some fatty acids, α-ketoacids, and α-hydroxyacids originating from amino acid metabolism as well as polyketide-deri...

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

authors： Peng C,Pu JY,Song LQ,Jian XH,Tang MC,Tang GL

更新日期：2012-05-29 00:00:00

abstract：:Banded iron formations (BIFs) record a time of extensive Fe deposition in the Precambrian oceans, but the sources and pathways for metals in BIFs remain controversial. Here, we present Fe- and Nd-isotope data that indicate two sources of Fe for the large BIF units deposited 2.5 billion y ago. High-εNd and -δ(56)Fe sig...

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

authors： Li W,Beard BL,Johnson CM

更新日期：2015-07-07 00:00:00

abstract：:Etioplasts isolated from barley leaves and purified on a Sephadex G-50 (coarse) column were characterized by electron microscopy and nucleic acid analysis. The majority of etioplasts retained an intact outer envelope, and contamination by other fragments was extremely low. The level of gibberellin-like substances extr...

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

authors： Evans A,Smith H

更新日期：1976-01-01 00:00:00

abstract：:Engagement of high-affinity IgE receptors leads to activation of tyrosine and serine/threonine kinases and the immediate phosphorylation of receptor beta (serine and tyrosine) and gamma (threonine and tyrosine) chains. Receptor disengagement leads to dephosphorylation of beta and gamma chains via the action of undefin...

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

authors： Paolini R,Numerof R,Kinet JP

更新日期：1992-11-15 00:00:00

abstract：:We report on the location of the chain part of the retinylidene chromophore in the projected density of bacteriorhodopsin as determined by neutron diffraction from the two-dimensional purple membrane lattice. For this purpose, partially deuterated retinal was synthesized containing 10 deuterons at positions C-8, C-10,...

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

authors： Seiff F,Wallat I,Ermann P,Heyn MP

更新日期：1985-05-01 00:00:00

abstract：:Seven antigenic variants obtained from a single field isolate of foot-and-mouth disease virus, serotype A12, differ only at residues 148 and 153 in the immunodominant loop of viral protein VP1. Synthetic peptides corresponding to the region 141-160 are highly immunogenic. UV circular dichroism shows that (i) in aqueou...

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

authors： France LL,Piatti PG,Newman JF,Toth I,Gibbons WA,Brown F

更新日期：1994-08-30 00:00:00

abstract：:Because the insolubility of the scrapie prion protein (PrP(Sc)) has frustrated structural studies by x-ray crystallography or NMR spectroscopy, we used electron crystallography to characterize the structure of two infectious variants of the prion protein. Isomorphous two-dimensional crystals of the N-terminally trunca...

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

authors： Wille H,Michelitsch MD,Guenebaut V,Supattapone S,Serban A,Cohen FE,Agard DA,Prusiner SB

更新日期：2002-03-19 00:00:00

abstract：:The stimulatory activity of peptides from the alpha 1 domain of the major histocompatibility complex (MHC) class I antigen on adipose cell glucose transport was previously shown to require a preformed, ordered conformation of the peptide. The two peptides studied previously were Dk-(61-85) (ERETQIAKGNEQSFRVDLRTLLRYY) ...

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

authors： Stagsted J,Mapelli C,Meyers C,Matthews BW,Anfinsen CB,Goldstein A,Olsson L

更新日期：1993-08-15 00:00:00

abstract：:IFNs are a family of cytokines that are essential for the antiviral response in vertebrates. Not surprisingly, viruses have adapted to encode virulence factors to cope with the IFN response. Intriguingly, we show here that all three types of interferons, IFN-α, IFN-γ, and IFN-λ, efficiently promote infection by a huma...

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

authors： Zhao X,Guo F,Liu F,Cuconati A,Chang J,Block TM,Guo JT

更新日期：2014-05-06 00:00:00

abstract：:The Belgrade (b) rat has an autosomal recessively inherited, microcytic, hypochromic anemia associated with abnormal reticulocyte iron uptake and gastrointestinal iron absorption. The b reticulocyte defect appears to be failure of iron transport out of endosomes within the transferrin cycle. Aspects of this phenotype ...

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

authors： Fleming MD,Romano MA,Su MA,Garrick LM,Garrick MD,Andrews NC

更新日期：1998-02-03 00:00:00

abstract：:A simple in vitro system that supports chromatin assembly was developed for Saccharomyces cerevisiae. The assembly reaction is ATP-dependent, uses soluble histones and assembly factors, and generates physiologically spaced nucleosomes. We analyze the pathway of histone recruitment into nucleosomes, using this system i...

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

authors： Schultz MC,Hockman DJ,Harkness TA,Garinther WI,Altheim BA

更新日期：1997-08-19 00:00:00

abstract：:The recent completion of the deletion of essentially all of the ORFs in yeast is an important new resource for identifying the phenotypes of unknown genes. Each ORF is replaced with a cassette containing unique tag sequences that allow rapid parallel analysis of strains in a pool by using hybridization to a high-densi...

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

authors： Birrell GW,Giaever G,Chu AM,Davis RW,Brown JM

更新日期：2001-10-23 00:00:00

abstract：:Plasmids have been constructed to generate substrates for the study of proteinases 2A and 3C of poliovirus. They contain the P1 (capsomer precursor) region of the poliovirus genome or P1 and part of P2 (a nonstructural precursor), which can be transcribed and translated in vitro. A transcript containing the entire 5' ...

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

authors： Nicklin MJ,Kräusslich HG,Toyoda H,Dunn JJ,Wimmer E

更新日期：1987-06-01 00:00:00

abstract：:Incubation of neuroblastoma X glioma hybrid cells for 12-97 hr with methionine-enkephalin results in an increase in adenylate cyclase activity [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] that is mediated by the opiate receptor. The results show that cells become tolerant to, and dependent upon, enkephalin. ...

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

authors： Lampert A,Nirenberg M,Klee WA

更新日期：1976-09-01 00:00:00

abstract：:The vacuolated lens (vl) mouse mutant causes congenital cataracts and neural tube defects (NTDs), with the NTDs being caused by abnormal neural fold apposition and fusion. Our positional cloning of vl indicates these phenotypes result from a deletion mutation in an uncharacterized orphan G protein-coupled receptor (GP...

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

authors： Matteson PG,Desai J,Korstanje R,Lazar G,Borsuk TE,Rollins J,Kadambi S,Joseph J,Rahman T,Wink J,Benayed R,Paigen B,Millonig JH

更新日期：2008-02-12 00:00:00

abstract：:By Southern blotting and hybridization analysis using 32P-labeled poly(dT-dG) . poly(dC-dA) as a probe, we have found, in eukaryotic genomes, a huge number of stretches of dT-dG alternating sequence, a sequence that has been shown to adopt the Z-DNA conformation under some conditions. This sequence was found in all eu...

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

authors： Hamada H,Petrino MG,Kakunaga T

更新日期：1982-11-01 00:00:00

abstract：:The DNA sequence of a tryptophan synthase gene and the flanking 5' and 3' regions has been determined for Arabidopsis thaliana. The sequence encodes only the beta subunit domain, indicating that alpha and beta subunits are specified by separate genes. The gene contains four introns and encodes 470 amino acid residues....

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

authors： Berlyn MB,Last RL,Fink GR

更新日期：1989-06-01 00:00:00

abstract：:Cell membrane contact induces the de novo expression of choline O-acetyltransferase (CAT; acetyl-CoA: choline O-acetyltransferase, EC 2.3.1.6) activity in cultures of virtually pure neonatal rat dissociated sympathetic neurons. To identify molecular mechanisms underlying membrane-associated CAT induction, the responsi...

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

authors： Adler JE,Schleifer LS,Black IB

更新日期：1989-02-01 00:00:00

abstract：:DNA toroids produced by the condensation of lambda phage DNA with hexammine cobalt (III) have been investigated by cryoelectron microscopy. Image resolution obtained by this technique has allowed unprecedented views of DNA packing within toroidal condensates. Toroids oriented coplanar with the microscope image plane e...

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

authors： Hud NV,Downing KH

更新日期：2001-12-18 00:00:00

abstract：:The biological function of the soluble form of the amyloid beta-protein (ABP) was examined by assaying its interaction with neuronal receptors expressed in Xenopus oocytes. ABP weakly activated tachykinin receptors, but in the presence of N-methyl-D-aspartate and alpha-amino-3-hydroxy-5-methylisoxazole-4- propionate-t...

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

authors： Kimura H,Schubert D

更新日期：1993-08-15 00:00:00

abstract：:Prototrophic hybrids formed from an adenine-requiring Chinese hamster cell and human fibroblasts uniformly display new esterase activity that differs from that of either parental cell in electrophoretic mobility and substrate specificity. The hybrids that grew in the selective medium and possessed the new esterase act...

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

authors： Kao FT,Puck TT

更新日期：1972-11-01 00:00:00

abstract：:Levinthal's paradox is that finding the native folded state of a protein by a random search among all possible configurations can take an enormously long time. Yet proteins can fold in seconds or less. Mathematical analysis of a simple model shows that a small and physically reasonable energy bias against locally unfa...

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

authors： Zwanzig R,Szabo A,Bagchi B

更新日期：1992-01-01 00:00:00

abstract：:Cortical blood flow at the level of individual capillaries and the coupling of neuronal activity to flow in capillaries are fundamental aspects of homeostasis in the normal and the diseased brain. To probe the dynamics of blood flow at this level, we used two-photon laser scanning microscopy to image the motion of red...

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

authors： Kleinfeld D,Mitra PP,Helmchen F,Denk W

更新日期：1998-12-22 00:00:00

abstract：:The MLL (mixed-lineage leukemia) gene is involved in many chromosomal translocations associated with acute myeloid and lymphoid leukemia. We previously identified a transcriptional repression domain in MLL, which contains a region with homology to DNA methyltransferase. In chromosomal translocations, the MLL repressio...

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

authors： Xia ZB,Anderson M,Diaz MO,Zeleznik-Le NJ

更新日期：2003-07-08 00:00:00

abstract：:Truncation selection is known to be the most efficient form of directional selection. When this is modified so that the fitness increases linearly over a range of one or two standard deviations of the value of the selected character, the efficiency is reduced, but not greatly. When truncation selection is compared to ...

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

authors： Crow JF,Kimura M

更新日期：1979-01-01 00:00:00