Abstract:
:We present a phylogenetic analysis to determine whether a given tRNA molecule was established in evolution before its cognate aminoacyl-tRNA synthetase. The earlier appearance of tRNA versus their metabolically related enzymes is a prediction of the RNA world theory, but the available synthetase and tRNA sequences previously had not allowed a formal comparison of their relative time of appearance. Using data recently obtained from the emerging genome projects, our analysis points to the extant forms of lysyl-tRNA synthetase being preceded in evolution by the establishment of the identity of lysine tRNA.
journal_name
Proc Natl Acad Sci U S Aauthors
Ribas de Pouplana L,Turner RJ,Steer BA,Schimmel Pdoi
10.1073/pnas.95.19.11295subject
Has Abstractpub_date
1998-09-15 00:00:00pages
11295-300issue
19eissn
0027-8424issn
1091-6490journal_volume
95pub_type
杂志文章abstract::Paired immunoglobulin-like type 2 receptor α (PILRα) and β (PILRβ) belong to the PILR family and are related to innate immune regulation in various species. Despite their high sequence identity, PILRα and PILRβ are shown to have variant sialic acid (SA) binding avidities. To explore the molecular basis of this interac...
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.1320716111
更新日期:2014-06-03 00:00:00
abstract::A mechanism of ion transport across membranes is reported. Microbial transport of Fe(3+) generally delivers iron, a growth-limiting nutrient, to cells via highly specific siderophore-mediated transport systems. In contrast, iron transport in the fresh water bacterium Aeromonas hydrophila is found to occur by means 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.200318797
更新日期:2000-09-26 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::We have isolated from vaccinia virus cores an enzyme, 5'-phosphate-polyribonucleotide kinase, that in the presence of ATP and Mg2+ catalyzes the conversion of 5'-phosphate and 5'-diphosphate termini of RNA to the 5'-triphosphate species. With the exception of dATP, other nucleoside triphosphates were inactive as phosp...
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.75.10.4793
更新日期:1978-10-01 00:00:00
abstract::Even in the absence of sensory stimulation, the neocortex shows complex spontaneous activity patterns, often consisting of alternating "DOWN" states of generalized neural silence and "UP" states of massive, persistent network activity. To investigate how this spontaneous activity propagates through neuronal assemblies...
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.0605643104
更新日期:2007-01-02 00:00:00
abstract::Trace greenhouse gases are a fundamentally important component of Earth's global climate system sensitive to global change. However, their concentration in the pre-Pleistocene atmosphere during past warm greenhouse climates is highly uncertain because we lack suitable geochemical or biological proxies. This long-stand...
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.1102409108
更新日期:2011-06-14 00:00:00
abstract::Normal rat mast cells were stimulated by antibodies against IgE receptors (anti-RBL) or by anti-IgE, and [3H]methyl group incorporation into phospholipids, 45Ca uptake, and histamine release were examined. Anti-RBL or its F(ab')2 fragments and anti-IgE induced an increase in the incorporation of [3H]methyl into phosph...
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.77.4.1903
更新日期:1980-04-01 00:00:00
abstract::RNA of a common strain of tobacco mosaic virus was sequentially reconstituted first with protein of the same strain and then with protein of a tomato strain. The reconstituted particles were treated with specific antibodies against the two strain particles and were examined electron microscopically to locate the regio...
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.74.5.1913
更新日期:1977-05-01 00:00:00
abstract::Amyloid beta-protein (Abeta) is linked to neuronal injury and death in Alzheimer's disease (AD). Of particular relevance for elucidating the role of Abeta in AD is new evidence that oligomeric forms of Abeta are potent neurotoxins that play a major role in neurodegeneration and the strong association of the 42-residue...
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.222681699
更新日期:2003-01-07 00:00:00
abstract::A discussion of the range of applicability of Forster long-range energy transfer in the determination of macromolecular dimensions and conformational dynamics is given. Emphasis is laid on the effect of restrictions in the orientational freedom of donor and acceptor and on the importance of the orientational averaging...
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.73.2.271
更新日期:1976-02-01 00:00:00
abstract::Our ability to interpret seismic observations including the seismic discontinuities and the density and velocity profiles in the earth's interior is critically dependent on the accuracy of pressure measurements up to 364 GPa at high temperature. Pressure scales based on the reduced shock-wave equations of state alone ...
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.0609013104
更新日期:2007-05-29 00:00:00
abstract::Alterations of human chromosome 8p occur frequently in many tumors. We identified a 1.5-Mb common region of allelic loss on 8p22 by allelotype analysis. cDNA selection allowed isolation of several genes, including FEZ1. The predicted Fez1 protein contained a leucine-zipper region with similarity to the DNA-binding dom...
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.96.7.3928
更新日期:1999-03-30 00:00:00
abstract::Loss-of-function mutations in the genes associated with primary microcephaly (MCPH) reduce human brain size by about two-thirds, without producing gross abnormalities in brain organization or physiology and leaving other organs largely unaffected [Woods CG, et al. (2005) Am J Hum Genet 76:717-728]. There is also evide...
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.0908454107
更新日期:2010-01-05 00:00:00
abstract::Flagellin and several other external components of the bacterial flagellum are thought to be exported, not by the general N-terminal signal peptide-dependent pathway, but by a flagellum-specific pathway involving a central channel in the flagellum itself. We have constructed a variety of mutant alleles of the Escheric...
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.86.13.4953
更新日期:1989-07-01 00:00:00
abstract::Proteins internalized into the endocytic pathway are usually degraded. Efficient proteolysis requires denaturation, induced by acidic conditions within lysosomes, and reduction of inter- and intrachain disulfide bonds. Cytosolic reduction is mediated enzymatically by thioredoxin, but the mechanism of lysosomal reducti...
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.97.2.745
更新日期:2000-01-18 00:00:00
abstract::The method presented here refines molecular conformations directly against projections of single particles measured by electron microscopy. By optimizing the orientation of the projection at the same time as the conformation, the method is well-suited to two-dimensional class averages from cryoelectron microscopy. Suc...
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.1205945109
更新日期:2012-06-19 00:00:00
abstract::The hypernociceptive effects of cytokines [TNF-alpha, keratinocyte-derived chemokine (KC), and IL-1beta] and their participation in carrageenan (Cg)-induced inflammatory hypernociception in mice were investigated. Nociceptor sensitization (hypernociception) was quantified with an electronic version of the von Frey fil...
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.0409225102
更新日期:2005-02-01 00:00:00
abstract::The 3' flanking region of the apolipoprotein B (apoB) gene contains a hypervariable region consisting of a variable number of tandemly repeated short A + T-rich DNA sequences (VNTRs). We present a general method that utilizes the polymerase chain reaction to rapidly and accurately type this and other VNTR loci. We use...
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.86.1.212
更新日期:1989-01-01 00:00:00
abstract::The ability of polynucleotides or polynucleotide duplexes such as poly(I).poly(C) to induce interferon production is proposed to depend on the existence of certain stable glycosidic orientations. It appears that a slight increase in instability of 1--3 kcal/mole (1 cal = 4.184 J) in the conformational regions near 20 ...
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.76.3.1018
更新日期:1979-03-01 00:00:00
abstract::Hepatitis A virus (HAV) infects ∼1.4 million people annually and, although there is a vaccine, there are no licensed therapeutic drugs. HAV is unusually stable (making disinfection problematic) and little is known of how it enters cells and releases its RNA. Here we report a potent HAV-specific monoclonal antibody, R1...
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.1616502114
更新日期:2017-01-24 00:00:00
abstract::The recent characterization of the prokaryotic Cys(2)His(2) zinc-finger domain, identified in Ros protein from Agrobacterium tumefaciens, has demonstrated that, although possessing a similar zinc coordination sphere, this domain is structurally very different from its eukaryotic counterpart. A search in the databases ...
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.0810003106
更新日期:2009-04-28 00:00:00
abstract::It is suggested that active transport, muscle contraction, and ribosomal translocation may all make use of a common allosteric mechanism in which ATP or GTP serves as both the effector and substrate and in which a conformational change in a protein (enzyme) moves or exerts a force on a second ligand. The enzymatic spl...
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.64.1.267
更新日期:1969-09-01 00:00:00
abstract::Agrobacterium is a unique model system as well as a major biotechnological tool for genetic manipulation of plant cells. It is still unknown, however, whether host cellular factors exist that are limiting for infection, and whether their overexpression in plant cells can increase the efficiency of the infection. Here,...
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.162304099
更新日期:2002-08-06 00:00:00
abstract::Superhard metals are of interest as possible replacements with enhanced properties over the metal carbides commonly used in cutting, drilling, and wear-resistant tooling. Of the superhard metals, the highest boride of tungsten--often referred to as WB4 and sometimes as W(1-x)B3--is one of the most promising candidates...
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.1415018112
更新日期:2015-03-17 00:00:00
abstract::The ability to regulate gene expression through transcription initiation underlies the adaptability and survival of all bacteria. Recent work has revealed that the transcription machinery in many bacteria diverges from the paradigm that has been established in Escherichia coliMycobacterium tuberculosis (Mtb) encodes t...
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.1900176116
更新日期:2019-07-02 00:00:00
abstract::We describe a functional profiling strategy to identify and characterize subtypes of neurons present in a peripheral ganglion, which should be extendable to neurons in the CNS. In this study, dissociated dorsal-root ganglion neurons from mice were exposed to various pharmacological agents (challenge compounds), while ...
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.1118833109
更新日期:2012-01-31 00:00:00
abstract::The transcription factor and tumor suppressor protein p53 is frequently inactivated in human cancers. In many cases, p53 gene mutations result in high levels of inactive, full-length p53 protein with one amino acid change in the core domain that recognizes p53 DNA-binding sites. The ability to endow function to mutate...
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.0401162101
更新日期:2004-04-06 00:00:00
abstract::We have employed a combination of temperature-dependent UV absorption spectroscopy, circular dichroism, and batch calorimetry to characterize the binding of actinomycin D to a series of oligomeric DNA duplexes. We find the duplex [d(CGTCGACG)]2 to be unique in its ability to bind actinomycin D strongly despite the abs...
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.86.11.3968
更新日期:1989-06-01 00:00:00
abstract::The novel immune-type receptor (NITR) genes encode a unique multigene family of leukocyte regulatory receptors, which possess an extracellular Ig variable (V) domain and may function in innate immunity. Artificial chromosomes that encode zebrafish NITRs have been assembled into a contig spanning approximately 350 kb. ...
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.0405242101
更新日期:2004-11-02 00:00:00
abstract::The computation of motion plays a central role in visual orientation. The fly has been successfully used as a model system for analyzing the mechanisms underlying motion detection. Thereby, much attention has been paid to a neuronal circuit of individually identifiable neurons in the third visual ganglion that extract...
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.89.9.4139
更新日期:1992-05-01 00:00:00