Abstract:
:2'-Deoxyadenosine 5'-O-(1-thiotriphosphate) (dATP[alpha S]) was introduced into the 3' ends of DNA restriction fragments with Escherichia coli DNA polymerase I to give phosphorothioate internucleotide linkages. Such "capped" 3' ends were found to be resistant to exonuclease III digestion. Moreover, the resistance to digestion is great enough that, under conditions used by us, just one strand of a double helix is digested by exonuclease III when a cap is placed at only one end; when digestion is carried to completion, this results in production of intact single strands. When digestion with exonuclease III is limited and is followed by S1 nuclease treatment, double-stranded DNA fragments asymmetrically shortened from just one side are produced. In this was thousands of nucleotides can be selectively removed from one end of a restriction fragment. In vitro introduction of phosphorothioate linkages into one end of a linearized replicative plasmid, followed by exonuclease III and S1 nuclease treatments, gives rise to truncated forms that, upon circularization by blunt-end ligation, transform E. coli and replicate in vivo.
journal_name
Proc Natl Acad Sci U S Aauthors
Putney SD,Benkovic SJ,Schimmel PRdoi
10.1073/pnas.78.12.7350subject
Has Abstractpub_date
1981-12-01 00:00:00pages
7350-4issue
12eissn
0027-8424issn
1091-6490journal_volume
78pub_type
杂志文章abstract::Tetrahymena ribozymes hold promise for repairing genetic disorders but are largely limited by their modest splicing efficiency and low production of final therapeutic proteins. Ribozyme evolution in intact living mammalian cells would greatly facilitate the discovery of new ribozyme variants with high in vivo activity...
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.2036553100
更新日期:2003-12-09 00:00:00
abstract::Kinetic analysis of the in vitro reconstitution of glyceraldehyde-3-phosphate dehydrogenase [D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC 1.2.1.12] from yeast showed that both oxidized and reduced coenzyme enhance the transconformation reaction, which is rate limiting in the sequential foldin...
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.77.4.1966
更新日期:1980-04-01 00:00:00
abstract::Recent reports on the dystrophic mouse mutant suggest that the prominent extracellular matrix component of peripheral nerve tissues plays an important role in peripheral nerve development. We have examined the disposition of two prominent extracellular matrix components, fibronectin and laminin, both in mature periphe...
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.80.12.3850
更新日期:1983-06-01 00:00:00
abstract::The eukaryotic DNA sliding clamp that keeps DNA polymerase engaged at a replication fork, called proliferating cell nuclear antigen (PCNA), is loaded onto the 3' ends of primer DNA through its interaction with a heteropentameric protein complex called replication factor C (RFC). The ATPase activity of RFC is necessary...
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.97.26.14127
更新日期:2000-12-19 00:00:00
abstract::Cell couples have been formed by mixing an antigen- and Ia-specific cloned helper T-cell line with a B-cell hybridoma presenting the antigen. By immunofluorescence observations, we have shown that the microtubule-organizing center (MTOC) inside the helper T cell, but not in the bound antigen-presenting cell, becomes 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.83.16.6080
更新日期:1986-08-01 00:00:00
abstract::The free radicals nitric oxide and superoxide anion react to form peroxynitrite (ONOO-), a highly toxic oxidant species. In vivo formation of ONOO- has been demonstrated in shock and inflammation. Herein we provide evidence that cytotoxicity in cells exposed to ONOO- is mediated by DNA strand breakage and the subseque...
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.93.5.1753
更新日期:1996-03-05 00:00:00
abstract::The binding of invariant chain to major histocompatibility complex (MHC) proteins is an important step in processing of MHC class II proteins and in antigen presentation. The question of how invariant chain can bind to all MHC class II proteins is central to understanding these processes. We have employed molecular mo...
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.92.18.8269
更新日期:1995-08-29 00:00:00
abstract::The functional groups found among the RNA bases and in the phosphoribose backbone represent a limited repertoire from which to construct a ribozyme active site. This work investigates the possibility that simple RNA phosphodiester and hydroxyl functional groups could catalyze amide bond synthesis. Reaction of amine gr...
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.212527799
更新日期:2002-11-12 00:00:00
abstract::We have previously shown that mammary epithelial specific expression of the activated erbB2 allele under the control of the endogenous promoter in mice resulted in the formation of mammary adenocarcinomas. To assess whether mammary tumorigenesis in this model is influenced by the developmental window of expression, we...
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.0306802101
更新日期:2004-04-06 00:00:00
abstract::The concentration of triglyceride-rich lipoproteins containing apolipoprotein (apo) B-48 (chylomicrons) and apo B-100 (very low density lipoproteins) was measured in blood plasma of healthy young men after an ordinary meal containing one-third of daily energy and fat. Plasma obtained in the postabsorptive state and at...
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.90.5.2069
更新日期:1993-03-01 00:00:00
abstract::Intracisternal A-particles were isolated from three different myeloma lines in BALB/c mice and from cultured neuroblastoma cells of A/J origin. All preparations contained a major structural protein with an apparent molecular weight near 70,000 as estimated by electrophoretic mobility in sodium dodecyl sulfate-containi...
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.69.1.218
更新日期:1972-01-01 00:00:00
abstract::Elastogenesis is a hierarchical process by which cells form functional elastic fibers, providing elasticity and the ability to regulate growth factor bioavailability in tissues, including blood vessels, lung, and skin. This process requires accessory proteins, including fibulin-4 and -5, and latent TGF binding protein...
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.1901048116
更新日期:2019-10-08 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::In a significant fraction of the Escherichia coli cytosolic proteins, the N-terminal methionine residue incorporated during the translation initiation step is excised. The N-terminal methionine excision is catalyzed by methionyl-aminopeptidase (MAP). Previous studies have suggested that the action of this enzyme could...
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.86.21.8247
更新日期:1989-11-01 00:00:00
abstract::The Alu element has been a major source of new exons during primate evolution. Thousands of human genes contain spliced exons derived from Alu elements. However, identifying Alu exons that have acquired genuine biological functions remains a major challenge. We investigated the creation and establishment of Alu exons ...
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.1012834108
更新日期:2011-02-15 00:00:00
abstract::Hybridization in plants leads to transinteractions between the parental genomes and epigenomes that can result in changes to both 24 nt siRNA and cytosine methylation ((m)C) levels in the hybrid. In Arabidopsis the principle processes altering the hybrid methylome are Trans Chromosomal Methylation (TCM) and Trans Chro...
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.1323656111
更新日期:2014-02-04 00:00:00
abstract::Initial attempts to correlate the distribution of gene density (number of gene loci per unit length on the linkage map) with the distribution of lengths of coding sequences have led to the observation that 46% of approximately 1000 sampled proteins in Escherichia coli have molecular masses of n X 14,000 +/- 2500 dalto...
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.83.5.1198
更新日期:1986-03-01 00:00:00
abstract::Physical and biological systems are often involved with coupled processes of different time scales. In the system with electronic and atomic motions, for example, the interplay between the atomic motion along the same energy landscape and the electronic hopping between different landscapes is critical: the system beha...
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.1305604110
更新日期:2013-09-10 00:00:00
abstract::The inability of adenovirus to infect primitive hematopoietic cells presents an obstacle to the use of adenovirus vectors for gene transfer to these cell types. Therefore, expanding the tropism of adenovirus vectors to unique cell surface antigens would be an important development for gene therapy protocols. In this s...
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.96.16.8855
更新日期:1999-08-03 00:00:00
abstract::We have examined the extent of tyrosine phosphorylation of talin, a component of the cytoskeleton localized in the focal adhesions and, therefore, a potential substrate of p60v-src, the transforming protein of Rous sarcoma virus. p60v-src is a tyrosine kinase that induces high levels of phosphotyrosine and the disorga...
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.83.15.5507
更新日期:1986-08-01 00:00:00
abstract::A decade ago, it seemed rational that our rapidly increasing knowledge of the molecular identities of tumor antigens and a deeper understanding of basic immunology would point the way to an effective therapeutic cancer vaccine. Significant progress has been made, but we do not yet have a cancer vaccine that can reliab...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.0404839101
更新日期:2004-10-05 00:00:00
abstract::Clinically isolated syndrome (CIS) refers to the earliest clinical manifestation of multiple sclerosis (MS). Currently there are no prognostic biological markers that accurately predict conversion of CIS to clinically definite MS (CDMS). Furthermore, the earliest molecular events in MS are still unknown. We used micro...
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.0805065105
更新日期:2008-08-19 00:00:00
abstract::The remarkable fidelity of most DNA polymerases depends on a series of early steps in the reaction pathway which allow the selection of the correct nucleotide substrate, while excluding all incorrect ones, before the enzyme is committed to the chemical step of nucleotide incorporation. The conformational transitions 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.0910909107
更新日期:2010-01-12 00:00:00
abstract::The structure of promoter chromatin determines the ability of transcription factors (TFs) to bind to DNA and therefore has a profound effect on the expression levels of genes. However, the role of spontaneous nucleosome movements in this process is not fully understood. Here, we developed a single-molecule optical twe...
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.1815424116
更新日期:2019-06-18 00:00:00
abstract::We studied regional cerebral blood flow using the H2(15)O method while normal subjects performed four similar tasks involving three-letter word beginnings (stems). Prior to each task, subjects studied a list of words. Local blood flow was then monitored during a 40-sec period while subjects (i) silently viewed word st...
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.89.5.1837
更新日期:1992-03-01 00:00:00
abstract::Aneuploidy is ubiquitous in cancer, and its phenotypes are inevitably dominant and abnormal. In view of these facts we recently proposed that aneuploidy is sufficient for carcinogenesis generating cancer-specific aneusomies via a chain reaction of autocatalytic aneuploidizations. According to this hypothesis a carcino...
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.251670699
更新日期:2002-05-14 00:00:00
abstract::Pheromone biosynthesis-activating neuropeptide (PBAN) regulates sex pheromone biosynthesis in female Helicoverpa (Heliothis) zea. Two oligonucleotide probes representing two overlapping amino acid regions of PBAN were used to screen 2.5 x 10(5) recombinant plaques, and a positive recombinant clone was isolated. Sequen...
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.89.1.142
更新日期:1992-01-01 00:00:00
abstract::The underlying causes of late-Holocene climate variability in the tropics are incompletely understood. Here we report a 1,500-year reconstruction of climate history and glaciation in the Venezuelan Andes using lake sediments. Four glacial advances occurred between anno Domini (A.D.) 1250 and 1810, coincident with sola...
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.0603118103
更新日期:2006-06-13 00:00:00
abstract::Size-selective mortality inevitably leads to a decrease in population density and exerts a direct negative effect on targeted size classes. But density and population size structure are also shaped by food-dependent processes, such as individual growth, maturation, and reproduction. Mortality relaxes competition and 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.0808279106
更新日期:2009-02-24 00:00:00
abstract::The transcription factor NFAT5/TonEBP, a member of the NFAT/Rel family of transcription factors, has been implicated in diverse cellular responses, including the response to osmotic stress, integrin-dependent cell migration, T cell activation, and the Ras pathway in Drosophila. To clarify the in vivo role of NFAT5, we...
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.0308703100
更新日期:2004-02-24 00:00:00