Abstract:
:A single, modified nucleoside in Escherichia coli tRNA, 6-(3-methyl-2-butenylamino)-2-methyl-thio-9-beta-D-ribofuranosylpurine, has been desulfurized with Raney nickel to afford its probable biosynthetic precursor. The limitations of the reaction at the nucleoside and tRNA levels and its lack of inhibition of the amino acid acceptor activity of tRNA are described.
journal_name
Proc Natl Acad Sci U S Aauthors
Hecht SM,Kirkegaard LH,Bock RMdoi
10.1073/pnas.68.1.48subject
Has Abstractpub_date
1971-01-01 00:00:00pages
48-51issue
1eissn
0027-8424issn
1091-6490journal_volume
68pub_type
杂志文章abstract::The addition of 10 mM glycine to a physiological saline bathing Ehrlich ascites tumor cells is followed by a slow increase in cell volume that plateaus between 15 and 30 min at a level approximately equal to 17% greater than the control volume; this increase is not observed when glycine is added to cells suspended in ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.85.1.279
更新日期:1988-01-01 00:00:00
abstract::Cytotactin is an extracellular matrix protein that is dynamically and transiently expressed in a place-dependent fashion during development by glial cells, fibroblasts, and several other cell types. In the present study, the effects of cytotactin on cell proliferation were examined in fibroblastic cells in culture. NI...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.24.11403
更新日期:1991-12-15 00:00:00
abstract::We report here studies of tryptophan (Trp) solvation dynamics in water and in the Pyrococcus furiosus rubredoxin protein, including the native and its apo and denatured forms. We also report results on energy transfer from Trp to the iron-sulfur [Fe-S] cluster. Trp fluorescence decay with the onset of solvation dynami...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.012582399
更新日期:2002-01-08 00:00:00
abstract::The β-1,3-glucan chrysolaminarin is the main storage polysaccharide of diatoms. In contrast to plants and green algae, diatoms and most other algal groups do not accumulate storage polysaccharides in their plastids. The diatom Phaeodactylum tricornutum possesses only a single gene encoding a putative β-1,3-glucan synt...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1719274115
更新日期:2018-05-01 00:00:00
abstract::Molecular cloning has established the primary structures of two precursors of the human pancreas growth hormone-releasing factor (hpGRF-44), somatocrinin. Both polypeptides contain the sequence of hpGRF-44 flanked by basic processing sites. Furthermore, the precursors include a putative signal sequence and a carboxyl-...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.80.14.4311
更新日期:1983-07-01 00:00:00
abstract::4"'-Diazomalonyldigitoxin and its isomer, 3"'-diazomalonyldigitoxin, have been synthesized at high specific radioactivity and used as photolabels for the Na,K-ATPase (ATP phosphohydrolase, EC 3.6.1.3) purified from Electrophorus electricus. Photoaffinity labeling experiments using both type I and type II complexes of ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.77.8.4529
更新日期:1980-08-01 00:00:00
abstract::The Cdc6 protein is essential for the assembly of pre-replicative complexes (pre-RCs) at origins of DNA replication in the budding yeast Saccharomyces cerevisiae. This reaction is blocked in vivo by the cyclin-dependent kinase Cdc28p, together with its regulatory subunits, the B type cyclins that are present throughou...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.11.5611
更新日期:1997-05-27 00:00:00
abstract::Microbes whose genomes are encoded by DNA and for which adequate information is available display similar genomic mutation rates (average 0.0034 mutations per chromosome replication, range 0.0025 to 0.0046). However, this value currently is based on only a few well characterized microbes reproducing within a narrow ra...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.141113098
更新日期:2001-07-03 00:00:00
abstract::Complement receptors (CRs), expressed notably on myeloid and lymphoid cells, play an essential function in the elimination of complement-opsonized pathogens and apoptotic/necrotic cells. In addition, these receptors are crucial for the cross-talk between the innate and adaptive branches of the immune system. CR3 (also...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1311261110
更新日期:2013-10-08 00:00:00
abstract::The size and metabolic rate of cells affect processes from the molecular to the organismal level. We present a quantitative, theoretical framework for studying relationships among cell volume, cellular metabolic rate, body size, and whole-organism metabolic rate that helps reveal the feedback between these levels of o...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0611235104
更新日期:2007-03-13 00:00:00
abstract::Abelson murine leukemia virus (A-MuLV) is derived from the thymotropic Moloney leukemia virus. However, injection of mice with A-MuLV by conventional routes results in rapidly arising peripheral and bone marrow lymphomas, not thymomas or T cell tumors. In this study thymomas have been induced by intrathymic injection ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.9.2917
更新日期:1982-05-01 00:00:00
abstract::Recent findings suggest that neurons can efficiently repair oxidatively damaged DNA, and that both DNA damage and repair are enhanced by activation of excitatory glutamate receptors. However, in pathological conditions such as ischemic stroke, excessive DNA damage can trigger the death of neurons. Oxidative DNA damage...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1204156109
更新日期:2012-09-11 00:00:00
abstract::Ethylene inhibits hypocotyl elongation in etiolated Arabidopsis seedlings. However, when Arabidopsis was grown in the light in the presence of ethylene or its precursor 1-aminocyclopropane-1-carboxylic acid (ACC), a marked induction of hypocotyl elongation occurred. This resulted from an increase in cell expansion rat...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.6.2756
更新日期:1997-03-18 00:00:00
abstract::Rhythmic, spontaneously pulsating cardiac cells cultured from newborn rats are immediately stimulated to beat faster by addition of a number of tubulin-binding agents but not by their non-tubulin-binding analogues. The tubulin-binding agents tested include vinblastine, vincristine, navelbine, two analogs of vinblastin...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.89.4.1256
更新日期:1992-02-15 00:00:00
abstract::We have used NMR spectroscopy and x-ray crystallography to determine the three-dimensional structure of PF1378 (Pfu Pop5), one of four protein subunits of archaeal RNase P that shares a homolog in the eukaryotic enzyme. RNase P is an essential and ubiquitous ribonucleoprotein enzyme required for maturation of tRNA. In...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0508004103
更新日期:2006-01-24 00:00:00
abstract::The cerebral cortex of mammals differentiates into functionally distinct areas that exhibit unique cytoarchitecture, connectivity, and molecular characteristics. Molecular specification of cells fated for limbic cortical areas, based on the expression of the limbic system-associated membrane protein (LAMP), occurs dur...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.89.9.3706
更新日期:1992-05-01 00:00:00
abstract::Many animals employ sex pheromones to find mating partners during their reproductive seasons. However, most sex pheromones of vertebrates remain to be identified. Over the past 20 years, steroids and prostaglandins have been identified as sex pheromones in several fishes. These pheromones are broadly termed "hormonal ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0604340103
更新日期:2006-10-17 00:00:00
abstract::GT-2 is a plant transcriptional activator that contains two separate, but similar, trihelix DNA-binding domains. GT-1 is similar to GT-2, although it contains only one of such domains. cDNAs that encode GT-2 were isolated from rice (OS-GT2) and Arabidopsis (AT-GT2). Evidence is presented for the existence of an Arabid...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.95.6.3318
更新日期:1998-03-17 00:00:00
abstract::We have cloned and partially characterized 24 loci from the human genome which are complementary to U1, U2, or U3, the three major species of small nuclear RNA (snRNA) in HeLa cells. When compared to the known U1 (human) and U2 (rat) snRNA sequences, the DNA sequences we report here for the complementary regions from ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.2.810
更新日期:1981-02-01 00:00:00
abstract::We have identified a major T-cell epitope, amino acids 48-54 (DRAHYNI, in one-letter code) in the E7 open reading frame protein of human papillomavirus (HPV) type 16. Lymph node cells from mice immunized with synthetic peptides containing DRAHYNI proliferated and produced interleukin when challenged in vitro with pept...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.13.5887
更新日期:1991-07-01 00:00:00
abstract::We are investigating the feasibility of using the positive-strand RNA virus Sindbis virus and its defective interfering (DI) particles as vectors for introducing foreign genes into cells. In previous work we showed by deletion mapping of a cloned cDNA derived from one of the DI RNAs that only nucleotides at the 3' and...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.84.14.4811
更新日期:1987-07-01 00:00:00
abstract::GTP-tubulin forms a cap on microtubule ends during aggregation. The bulk of the microtubule is GDP-tubulin. This complicates the usual simple kinetic theory of subunit exchange at microtubule ends to such an extent that Monte Carlo calculations are needed to handle the complications, except in special cases. The Monte...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.80.24.7520
更新日期:1983-12-01 00:00:00
abstract::We have identified a protein present only in erythroid cells that binds to two adjacent sites within an enhancer region of the chicken beta-globin locus. Mutation of the sites, so that binding by the factor can no longer be detected in vitro, leads to a loss of enhancing ability, assayed by transient expression in pri...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.85.16.5976
更新日期:1988-08-01 00:00:00
abstract::G-protein-coupled receptors (GPCRs) have recently joined the list of cell surface receptors that dimerize. Dimerization has been shown to alter the ligand-binding, signaling, and trafficking properties of these receptors. Recent studies have shown that GPCRs heterodimerize with closely related members, resulting in th...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.011384898
更新日期:2001-01-02 00:00:00
abstract::The nature of domestic cattle origins in Africa are unclear as archaeological data are relatively sparse. The earliest domesticates were humpless, or Bos taurus, in morphology and may have shared a common origin with the ancestors of European cattle in the Near East. Alternatively, local strains of the wild ox, the au...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.93.10.5131
更新日期:1996-05-14 00:00:00
abstract::Targeted gene disruption in the murine TOP3beta gene-encoding DNA topoisomerase IIIbeta was carried out. In contrast to the embryonic lethality of mutant mice lacking DNA topoisomerase IIIalpha, top3beta(-/-) nulls are viable and grow to maturity with no apparent defects. Mice lacking DNA topoisomerase IIIbeta have a ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.101132498
更新日期:2001-05-08 00:00:00
abstract::Immune responses of the malaria vector mosquito Anopheles gambiae were monitored systematically by the induced expression of five RNA markers after infection challenge. One newly isolated marker encodes a homologue of the moth Gram-negative bacteria-binding protein (GNBP), and another corresponds to a serine protease-...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.21.11508
更新日期:1997-10-14 00:00:00
abstract::Recent evidence suggests that the microbial community in the human intestine may play an important role in the pathogenesis of obesity. We examined 184,094 sequences of microbial 16S rRNA genes from PCR amplicons by using the 454 pyrosequencing technology to compare the microbial community structures of 9 individuals,...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0812600106
更新日期:2009-02-17 00:00:00
abstract::Message passing is a fundamental technique for performing calculations on networks and graphs with applications in physics, computer science, statistics, and machine learning, including Bayesian inference, spin models, satisfiability, graph partitioning, network epidemiology, and the calculation of matrix eigenvalues....
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1914893116
更新日期:2019-11-19 00:00:00
abstract::Biological organisms have evolved a wide range of immune mechanisms to defend themselves against pathogens. Beyond molecular details, these mechanisms differ in how protection is acquired, processed, and passed on to subsequent generations-differences that may be essential to long-term survival. Here, we introduce a m...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1600663113
更新日期:2016-08-02 00:00:00