Abstract:
:The error frequency of in vitro DNA synthesis using a natural DNA template has been measured with a biological assay for nucleotide substitutions. phiX174 DNA containing an amber mutation was copied in vitro by Escherichia coli DNA polymerase I, and the reversion frequency of the progeny DNA was determined by transfection of E. coli spheroplasts. E. coli polymerase I makes less than 1 mistake at the am3 locus for every 7700 nucleotides incorporated under standard reaction conditions. Substitution of Mn2+ for Mg2+ and unequal concentrations of deoxynucleoside triphosphate substrates raises this mutation frequency to greater than 1 in 1000. Thus, E. coli DNA polymerase I can copy natural DNA templates with high fidelity and its accuracy can be affected by alterations in reaction conditions.
journal_name
Proc Natl Acad Sci U S Aauthors
Weymouth LA,Loeb LAdoi
10.1073/pnas.75.4.1924subject
Has Abstractpub_date
1978-04-01 00:00:00pages
1924-8issue
4eissn
0027-8424issn
1091-6490journal_volume
75pub_type
杂志文章abstract::Burkitt's lymphomas, linked by previous studies with the DNA-containing Epstein-Barr virus, contain an RNA related in sequence to that of Rauscher leukemia virus. The present study establishes that the viral-related RNA found in Burkitt's tumors is a 70S component encapsulated with RNA-instructed DNA polymerase in a p...
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.70.3.737
更新日期:1973-03-01 00:00:00
abstract::Evidence is given for the existence of an electron transport pathway to oxygen in the thylakoid membranes of chloroplasts (chlororespiration). Plastoquinone is shown to be a redox carrier common to both photosynthetic and chlororespiratory pathways. It is shown that, in dark-adapted chloroplasts, an electrochemical 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.79.14.4352
更新日期:1982-07-01 00:00:00
abstract::Kinetic partitioning is predicted to be a general mechanism for proteins to fold into their well defined native three-dimensional structure from unfolded states following multiple folding pathways. However, experimental evidence supporting this mechanism is still limited. By using single-molecule atomic force microsco...
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.0706775105
更新日期:2008-02-12 00:00:00
abstract::Cystic fibrosis (CF) is an autosomal recessive disorder, the most common lethal genetic disease in Caucasians. Respiratory disease is the major cause of morbidity and mortality. Indeed, 95% of CF patients die of respiratory failure. Pseudomonas aeruginosa, an opportunistic pathogen, chronically infects the lungs of ov...
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.95.10.5718
更新日期:1998-05-12 00:00:00
abstract::In Arabidopsis, the two-dimensional expansion of leaves is regulated via the polarized elongation of cells. The ROTUNDIFOLIA3 (ROT3) protein, a member of the family of cytochromes P450, is involved in this process and regulates leaf length. Transgenic plants that overexpressed a wild-type ROT3 gene had longer leaves 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.96.16.9433
更新日期:1999-08-03 00:00:00
abstract::Messenger RNA from rat liver was partially purified by chromatography on cellulose on the basis of its poly(A) content. Microgram amounts of this RNA stimulate protein synthesis manyfold in a heterologous cell-free system, derived from Krebs ascites cells supplemented with reticulocyte initiation factors. The messenge...
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.70.4.1218
更新日期:1973-04-01 00:00:00
abstract::Mosquitoes transmit devastating human diseases because they need vertebrate blood for egg development. Metabolism in female mosquitoes is tightly coupled with blood meal-mediated reproduction, which requires an extremely high level of energy consumption. Functional analysis has shown that major genes encoding for enzy...
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.1619326114
更新日期:2017-03-28 00:00:00
abstract::The polyhedral borane ion [n-B20H18]2- reacts with liquid ammonia in the presence of a suitable base to produce an apical-equatorial (ae) isomer of the [B20H17NH3]3- ion, [1-(2'-B10H9)-2-NH3B10H8]3-. The structure of this product has been confirmed by 11B NMR spectroscopy and x-ray crystallography. This species underg...
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.91.8.3029
更新日期:1994-04-12 00:00:00
abstract::Seven morphologically nontransformed (flat) revertants with reduced tumorigenicity in vivo have been isolated from populations of Kirsten sarcoma virus-transformed NIH 3T3 cells transfected with a cDNA expression library of normal human fibroblasts. Each revertant harbors 1-10 recombinant plasmids per cell and retains...
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.86.1.162
更新日期:1989-01-01 00:00:00
abstract::Amphibian eggs and embryos as well as mammalian cells have been reported to contain an activity that unwinds double-stranded RNA. We have now found that adenosine residues have been modified in the RNA products of this unwinding activity. Although the modified RNA remains double-stranded, the modification causes the R...
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.86.8.2647
更新日期:1989-04-01 00:00:00
abstract::Metallo-β-lactamases (MBLs) hydrolyze almost all β-lactam antibiotics and are unaffected by clinically available β-lactamase inhibitors (βLIs). Active-site architecture divides MBLs into three classes (B1, B2, and B3), complicating development of βLIs effective against all enzymes. Bisthiazolidines (BTZs) are 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.1601368113
更新日期:2016-06-28 00:00:00
abstract::In skeletal muscle, dihydropyridine receptors and dihydropyridine-sensitive Ca2+ channels are preferentially localized in the transverse tubular membranes. Starting with an antigenic membrane fraction enriched in rabbit muscle transverse tubules (T-tubules), several monoclonal antibodies were produced by a fusion of 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.84.14.5019
更新日期:1987-07-01 00:00:00
abstract::In this paper, Vafa's approach to the formulation of conformal field theories is combined with the formal calculus developed in Frenkel, Lepowsky, and Meurman's work on the vertex operator construction of the Monster to give a geometric definition of vertex operator algebras. The main result announced is the equivalen...
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.88.22.9964
更新日期:1991-11-15 00:00:00
abstract::Fibronectins isolated from the conditioned medium produced by cultures of undifferentiated (monolayer) and differentiated (nodular) swine vascular smooth muscle cells are similar but not identical. In general, the nodular-cell fibronectin has a smaller molecular mass than monolayer-cell fibronectin and appears to lack...
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.82.9.2746
更新日期:1985-05-01 00:00:00
abstract::We know a great deal about the cellular response to starvation via AMPK, but less is known about the reaction to nutrient excess. Insulin resistance may be an appropriate response to nutrient excess, but the cellular sensors that link these parameters remain poorly defined. In the present study we provide evidence tha...
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.0902380106
更新日期:2009-10-20 00:00:00
abstract::While 9-O-acetylation of sialic acids has been reported in some mammalian tissues, the distribution of this modification on specific cell types and molecules is largely unknown. The influenza C virus hemagglutinin-esterase is a membrane-bound glycoprotein that binds specifically to 9-O-acetylated sialic acids (hemaggl...
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.91.16.7782
更新日期:1994-08-02 00:00:00
abstract::Several mouse models have already proved valuable for investigating hypertrophic responses to cardiac stress. Here, we characterize one caused by a well defined single copy transgene, RenTgMK, that genetically clamps plasma renin and thence angiotensin II at high levels. All of the transgenic males develop concentric ...
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.0307333101
更新日期:2004-03-02 00:00:00
abstract::A membrane-associated folate binding protein (FBP) and a soluble FBP, which is released into the culture medium, have been purified from human KB cells using affinity chromatography. By NaDodSO4/PAGE, both proteins have an apparent Mr of approximately 42,000. However, in the presence of Triton X-100, the soluble FBP e...
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.84.18.6546
更新日期:1987-09-01 00:00:00
abstract::The G-protein-coupled metabotropic glutamate receptor mGluR1 alpha and the ionotropic glutamate receptor GluR6 were examined for posttranslational palmitoylation. Recombinant receptors were expressed in baculovirus-infected insect cells or in human embryonic kidney cells and were metabolically labeled with [3H]palmiti...
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.92.26.12090
更新日期:1995-12-19 00:00:00
abstract::Neutrophils and dendritic cells when migrating in confined environments have been shown to actuate a directional choice toward paths of least hydraulic resistance (barotaxis), in some cases overriding chemotactic responses. Here, we investigate whether this barotactic response is conserved in the more primitive model ...
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.2000686117
更新日期:2020-10-13 00:00:00
abstract::The evolution of sensory systems has let mammals develop complicated tactile end organs to enable sophisticated sensory tasks, including social interaction, environmental exploration, and tactile discrimination. The Merkel disc, a main type of tactile end organ consisting of Merkel cells (MCs) and Aβ-afferent endings,...
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.1610176113
更新日期:2016-09-13 00:00:00
abstract::Alzheimer's disease (AD) and other neurodegenerative disorders are associated with the cytoplasmic aggregation of microtubule-associated protein tau. Recent evidence supports transcellular transfer of tau misfolding (seeding) as the mechanism of spread within an affected brain, a process reminiscent of viral infection...
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.1607215114
更新日期:2017-01-17 00:00:00
abstract::An electrophoretic karyotype of Aspergillus nidulans has been obtained using contour-clamped homogeneous electric field gel electrophoresis. Six chromosomal bands were separated, with two of the bands migrating as doublets. Using the Schizosaccharomyces pombe and Saccharomyces cerevisiae chromosomes as size standards,...
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.86.16.6260
更新日期:1989-08-01 00:00:00
abstract::A 16-amino acid residue peptide derived from a consensus motif of natural ferredoxins incorporates a tetranuclear iron sulfur cluster under physiological conditions. Successful assembly of the [4Fe-4S]2+/1+ cluster within a monomeric peptide was demonstrated using size exclusion chromatography, UV-visible, visible CD,...
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.93.26.15041
更新日期:1996-12-24 00:00:00
abstract::Prenylated Rab GTPases regulate intracellular vesicle trafficking in eukaryotic cells by associating with specific membranes and recruiting a multitude of Rab-specific effector proteins. Prenylation, membrane delivery, and recycling of all 60 members of the Rab GTPase family are regulated by two related molecules, Rab...
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.0701817104
更新日期:2007-07-24 00:00:00
abstract::We recently showed that culture-derived metacyclic trypomastigotes (CMT), but not epimastigotes (Epi), of the Miranda 88 strain of Trypanosoma cruzi evade lysis by the human alternative complement pathway because of inefficient binding of factor B to complement component C3b on the parasite surface. These results sugg...
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.85.1.193
更新日期:1988-01-01 00:00:00
abstract::We present the diploid genome sequence of the fungal pathogen Candida albicans. Because C. albicans has no known haploid or homozygous form, sequencing was performed as a whole-genome shotgun of the heterozygous diploid genome in strain SC5314, a clinical isolate that is the parent of strains widely used for molecular...
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.0401648101
更新日期:2004-05-11 00:00:00
abstract::Injection of antisense oligonucleotides was used to investigate the function of c-mos in murine oocytes. Oocytes injected with antisense c-mos oligonucleotides completed the first meiotic division but failed to initiate meiosis II. Instead, loss of c-mos function led to chromosome decondensation, reformation of a nucl...
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.86.18.7038
更新日期:1989-09-01 00:00:00
abstract::Misfolded proteins are eliminated from the endoplasmic reticulum (ER) by retrotranslocation into the cytosol, a pathway hijacked by certain viruses to destroy MHC class I heavy chains. The translocation of polypeptides across the ER membrane requires their polyubiquitination and subsequent extraction from the membrane...
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.0505006102
更新日期:2005-10-04 00:00:00
abstract::The interaction between mutations in the tumor-suppressor genes Apc and p53 was studied in congenic mouse strains to minimize the influence of polymorphic modifiers. The multiplicity and invasiveness of intestinal adenomas of Apc(Min/+) (Min) mice was enhanced by deficiency for p53. In addition, the occurrence of desm...
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.050585597
更新日期:2000-03-28 00:00:00