Abstract:
:Mitogen-stimulated scheduled DNA synthesis and DNA excision repair in human lymphocytes, as well as DNA polymerase a activity in a cell-free system, were inhibited by an electrophilic metabolite of benzo[a]pyrene. This metabolite, (+/-)-anti-(7r,8t)-dihydroxy-(9,10t)-epoxy-7,8,9,10-tetrahyd robenzo[a]pyrene (BPDE), covalently binds to cellular macromolecules and is mutagenic, carcinogenic, and cytotoxic. Human lymphocytes treated with BPDE at concentrations greater than 500-800 ng/ml showed decreases in both mitogen-stimulated DNA synthesis and excision repair of damaged DNA but did not exhibit overt cytotoxicity (excluded trypan blue and maintained an adenylate charge of greater than 0.7). Formation of, and total concentration of, BPDE-DNA adducts was not correlated with inhibition of DNA synthesis. DNA polymerase alpha studies using a cell-free system showed that enzymatic activity was not diminished when purified polymerase was treated with BPDE prior to the addition of template DNA. When the template DNA concentration was varied, BPDE inhibition of enzyme activity was uncompetitive. BPDE inhibition of enzyme activity was found to be noncompetitive when concentrations of dATP, dCTP, or dTTP were varied and competitive when the concentration of dGTP was varied. The data indicate that BPDE competitively inhibits interaction of dGTP with the template-DNA polymerase alpha complex.
journal_name
Proc Natl Acad Sci U S Aauthors
Busbee DL,Joe CO,Norman JO,Rankin PWdoi
10.1073/pnas.81.17.5300subject
Has Abstractpub_date
1984-09-01 00:00:00pages
5300-4issue
17eissn
0027-8424issn
1091-6490journal_volume
81pub_type
杂志文章abstract::"Functional connectivity" techniques are commonplace tools for studying brain organization. A critical element of these analyses is to distinguish variance due to neurobiological signals from variance due to nonneurobiological signals. Multiecho fMRI techniques are a promising means for making such distinctions based ...
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.1720985115
更新日期:2018-02-27 00:00:00
abstract::Antigen receptor variable region exons are assembled during lymphocyte development from variable (V), diversity (D), and joining (J) gene segments. Each germ-line gene segment is flanked by recombination signal sequences (RSs). Recombination-activating gene endonuclease initiates V(D)J recombination by cleaving a pair...
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.1019293108
更新日期:2011-02-01 00:00:00
abstract::The emergence of Vibrio cholerae O139 Bengal during 1992-1993 was associated with large epidemics of cholera in India and Bangladesh and, initially, with a total displacement of the existing V. cholerae O1 strains. However, the O1 strains reemerged in 1994 and initiated a series of disappearance and reemergence of eit...
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.0337468100
更新日期:2003-02-04 00:00:00
abstract::Substantial proportions of mammalian genomes comprise repetitive elements including endogenous retrotransposons. Although these play diverse roles during development, their appropriate silencing is critically important in maintaining genomic integrity in the host cells. The major mechanism for retrotransposon silencin...
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.1512775112
更新日期:2015-11-24 00:00:00
abstract::The pineal organ of the lizard Anolis carolinensis can be maintained for up to 10 days in superfused organ culture. During this time it synthesizes and releases melatonin into the medium flowing slowly over it. Collection of timed aliquots of medium and subsequent analysis for melatonin by radioimmunoassay reveal circ...
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.80.19.6119
更新日期:1983-10-01 00:00:00
abstract::Na(+)-NQR is a unique respiratory enzyme that couples the free energy of electron transfer reactions to electrogenic pumping of sodium across the cell membrane. This enzyme is found in many marine and pathogenic bacteria where it plays an analogous role to the H(+)-pumping complex I. It has generally been assumed that...
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.1002866107
更新日期:2010-07-13 00:00:00
abstract::A complementarity-determining region (CDR) of the mouse monoclonal antibody (mAb) F58 was constructed with specificity to a neutralization-inducing region of human immunodeficiency virus type 1 (HIV-1). The mAb has its major reactivity to the amino acid sequence I--GPGRA in the V3 viral envelope region. All CDRs inclu...
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.90.10.4374
更新日期:1993-05-15 00:00:00
abstract::We have measured the opioid receptor reserve in the guinea pig ileum myenteric plexus by means of the site-directed alkylating agent, beta-chlornaltrexamine. Treatment of the tissue with low (less than 10 nM) concentrations of beta-chlornaltrexamine caused a parallel shift of the log concentration-response curves for ...
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.81.22.7253
更新日期:1984-11-01 00:00:00
abstract::The unique ability of bovine papillomavirus (BPV-1) DNA to replicate as a stable, multicopy plasmid in transformed mouse cells has led to its utilization as a eukaryotic cloning vector. One limitation of the system has been the marked reduction in transformation efficiency when BPV-1 DNA or the subgenomic transforming...
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.79.23.7147
更新日期:1982-12-01 00:00:00
abstract::Adverse social conditions have been linked to a conserved transcriptional response to adversity (CTRA) in circulating leukocytes that may contribute to social gradients in disease. However, the CNS mechanisms involved remain obscure, in part because CTRA gene-expression profiles often track external social-environment...
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.1707373114
更新日期:2017-11-21 00:00:00
abstract::We have expressed the recombinant squid kinesin head domain in Escherichia coli and studied its interaction with microtubules. The head is active as a microtubule-stimulated ATPase and binds to microtubules, but it does not support microtubule gliding by itself. The head binds to both microtubules and depolymerized tu...
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.90.5.1671
更新日期:1993-03-01 00:00:00
abstract::Social status motivates much of human behavior. However, status may have been a relatively weak target of selection for much of human evolution if ancestral foragers tended to be more egalitarian. We test the "egalitarianism hypothesis" that status has a significantly smaller effect on reproductive success (RS) in for...
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.1606800113
更新日期:2016-09-27 00:00:00
abstract::Reactive oxygen species (ROS) play important roles in aging, inflammation, and cancer. Mitochondria are an important source of ROS; however, the spatiotemporal ROS events underlying oxidative cellular damage from dysfunctional mitochondria remain unresolved. To this end, we have developed and validated a chemoptogenet...
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.1910574116
更新日期:2019-09-10 00:00:00
abstract::We have isolated a gene from Escherichia coli homologous to the gene encoding the Mr 83,000 Drosophila heat shock protein (hsp83). In E. coli the protein homologous to hsp83 is a heat shock protein called C62.5. The predicted amino acid sequence of C62.5 is 41% and 42% identical to the Drosophila and human hsp83 prote...
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.84.15.5177
更新日期:1987-08-01 00:00:00
abstract::A method is proposed for analyzing fast (10 μs) single-molecule rotation trajectories in F1 adenosinetriphosphatase ([Formula: see text]-ATPase). This method is based on the distribution of jumps in the rotation angle that occur in the transitions during the steps between subsequent catalytic dwells. The method is com...
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.1915314116
更新日期:2019-12-17 00:00:00
abstract::Most new genes are thought to evolve from preexisting genes but duplications of entire genes or shuffling of preexisting exons provides only a limited repertoire of new sequences that can be presented to a cell. Only pieces that previously existed can be used in the construction and any further divergence depends on 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.91.16.7506
更新日期:1994-08-02 00:00:00
abstract::Neurogenesis has recently been observed in the adult human brain, suggesting the possibility of endogenous neural repair. However, the augmentation of neurogenesis in the adult human brain in response to neuronal cell loss has not been demonstrated. This study was undertaken to investigate whether neurogenesis occurs ...
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.1532244100
更新日期:2003-07-22 00:00:00
abstract::The rearrangement of immunoglobulin genes in B-lymphocyte precursors requires the expression of the recombination activating genes (Rag), which leads to the generation of a highly diverse B-cell repertoire. We can use the level of Rag-1 mRNA in the bone marrow as an index of its capacity to support the maturation of B...
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.91.25.11988
更新日期:1994-12-06 00:00:00
abstract::The mosquito midgut plays a central role in the sporogonic development of malaria parasites. We have found that polyclonal sera, produced against mosquito midguts, blocked the passage of Plasmodium falciparum ookinetes across the midgut, leading to a significant reduction of infections in mosquitoes. Anti-midgut mAbs ...
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.091447398
更新日期:2001-04-24 00:00:00
abstract::Reducing monosaccharides and oligosaccharides, after reductive amination, were separated and detected as their 3-(4-carboxybenzoyl)-2-quinolinecarboxaldehyde (CBQCA) derivatives by capillary electrophoresis/laser-induced fluorescence. Under optimized conditions, the minimum detectable quantities for monosaccharide sol...
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.88.6.2302
更新日期:1991-03-15 00:00:00
abstract::Herpes simplex virus type 1 (HSV-1) thymidine kinase is currently used as a suicide agent in the gene therapy of cancer. This therapy is based on the preferential phosphorylation of nucleoside analogs by tumor cells expressing HSV-1 thymidine kinase. However, the use of HSV-1 thymidine kinase is limited in part by the...
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.93.8.3525
更新日期:1996-04-16 00:00:00
abstract::We report direct evidence for the existence of an iron(IV)-hydroxide. Resonance Raman measurements on chloroperoxidase compound II (CPO-II) reveal an isotope ((18)O and (2)H)-sensitive band at nu(Fe-O) = 565 cm(-1). Preparation of CPO-II in H(2)O using H(2)(18)O(2) results in a red-shift of 22 cm(-1), while preparatio...
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.0603159103
更新日期:2006-08-15 00:00:00
abstract::Two mutants of Balb/c 3T3 cells defective in adhesiveness to substratum have been isolated. After exposure to a mutagen a cell population was treated with prostaglandin E1 and methylisobutylxanthine to elevate the cells 3':5'-cyclic AMP levels and adhesion to the substratum; then, loosley adherent cells were harvested...
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.73.2.544
更新日期:1976-02-01 00:00:00
abstract::Legionella pneumophila is the cause of Legionnaires' disease, which is a form of potentially fatal pneumonia. To identify genes required for virulence of the bacterium, a library of 1,386 L. pneumophila signature tagged transposon mutants was studied for guinea pig virulence. The mutants were screened in pools of 96 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.96.14.8190
更新日期:1999-07-06 00:00:00
abstract::Mutagen treatment of mouse P815 tumor cells produces tum- variants that are rejected by syngeneic mice because these variants express new surface antigens. These "tum- antigens" are recognized by cytolytic T lymphocytes but induce no detectable antibody response. Transfection of P815 cell line P1.HTR with DNA of tum- ...
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.85.7.2274
更新日期:1988-04-01 00:00:00
abstract::The rat mammary cell line Rama 25 [Bennett, D.C., Peachey, L.A., Durbin, H. & Rudland, P.S. (1978) Cell 15, 283--298] differentiates morphologically in vitro from a cuboidal form to a fusiform cell resembling myoepithelial cells. This differentiation occurs in all clonal isolates of the line. By using three different ...
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.75.12.6093
更新日期:1978-12-01 00:00:00
abstract::When we grasp and manipulate an object, populations of tactile nerve fibers become activated and convey information about the shape, size, and texture of the object and its motion across the skin. The response properties of tactile fibers have been extensively characterized in single-unit recordings, yielding importan...
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.1704856114
更新日期:2017-07-11 00:00:00
abstract::Phosphatidylinositol 3 (PI3)-kinase enhancer (PIKE) is a nuclear GTPase that enhances PI3-kinase activity in a GTP-dependent manner. Both PIKE-L and -A isoforms contain GTPase, pleckstrin homology (PH), ADP ribosylation factor-GTPase-activating protein, and two ankyrin repeats domains, and C-terminal ADP ribosylation ...
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.0507365102
更新日期:2005-11-15 00:00:00
abstract::Transferrin, a nonheme iron-binding protein, is polymorphic in most vertebrate species that have been examined. In pigeons, it is controlled by an autosomal gene, with two known codominant alleles, Tf(A) and Tf(B). The two alleles are found in nearly equal frequencies and the three genotypes are at Hardy-Weinberg equi...
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.69.2.326
更新日期:1972-02-01 00:00:00
abstract::Experimental work in animals has shown that memory formation depends on a cascade of molecular events. Here we show that variability of human memory performance is related to variability in genes encoding proteins of this signaling cascade, including the NMDA and metabotrobic glutamate receptors, adenylyl cyclase, CAM...
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.0510212103
更新日期:2006-03-14 00:00:00