Abstract:
:The polymerase chain reaction was used to amplify DNA surrounding the codon 12 region of the c-Ki-ras gene from C3H/10T1/2 cells and from a number of 3-methylcholanthrene (MCA)-transformed derivatives of these cells. Sequence analysis demonstrated that tumorigenic MCAC116/39 cells, known by DNA-mediated transfection to contain an activated c-Ki-ras oncogene, had a G----T transversion in the first position of codon 12 of this gene, resulting in a Gly12----Cys mutation. A combination of polymerase chain-reaction amplification and oligonucleotide hybridization demonstrated that three additional tumorigenic MCA transformants of C3H/10T1/2 cells had an identical mutation in the c-Ki-ras gene. In contrast, this mutation was not present in an MCA-induced C3H/10T 1/2 transformant that was not tumorigenic. The molecular specificity of this MCA-induced mutation resulting in C3H/10T1/2 tumorigenic transformants should provide an excellent system in which to study the roles of transcription, replication, repair, and exogenous factors in the establishment and expression of transformation and tumorigenicity.
journal_name
Proc Natl Acad Sci U S Aauthors
Chen AC,Herschman HRdoi
10.1073/pnas.86.5.1608subject
Has Abstractpub_date
1989-03-01 00:00:00pages
1608-11issue
5eissn
0027-8424issn
1091-6490journal_volume
86pub_type
杂志文章abstract::Many "workers" in north temperate colonies of the eusocial paper wasp Polistes fuscatus disappear within a few days of eclosion. We provide evidence that these females are pursuing an alternative reproductive strategy, i.e., dispersing to overwinter and become nest foundresses the following spring, instead of helping ...
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.95.23.13737
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.71.2.278
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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.81.7.2107
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1995-03-28 00:00:00
abstract::Caseinolytic proteases (ClpPs) are large oligomeric protein complexes that contribute to cell homeostasis as well as virulence regulation in bacteria. Although most organisms possess a single ClpP protein, some organisms encode two or more ClpP isoforms. Here, we elucidated the crystal structures of ClpP1 and ClpP2 fr...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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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.75.12.6240
更新日期:1978-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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abstract::We developed a method for rapidly generating thermostable enzyme variants. Our strategy is to introduce the gene coding for a given enzyme from a mesophilic organism into a thermophile, Bacillus stearothermophilus. Variants that retain the enzymatic activity at the higher growth temperatures of the thermophile are the...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1986-02-01 00:00:00
abstract::Data are presented that demonstrate that a dose of 10 R of x-rays to mature oocytes in Drosophila causes a significant increase, more than double the spontaneous frequency, of inherited translocations. The dose-frequency relationship appears to fit best a linear response between 10 and 50 R. From 50 to 500 R, the freq...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1971-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Plasma samples exhibiting alloalbuminemia on electrophoresis at pH 8.6 were requested from clinical laboratories throughout Sweden. Nine variants, each representing a different single point mutation, were found in 100 apparently unrelated Swedes. The overall prevalence of alloalbuminemia was estimated at 1:1700. Mutat...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1992-09-01 00:00:00
abstract::Previous reports have shown that γδ T cells are important for the elimination of malaria parasites in humans and mice. However, how γδ T cells are involved in protective immunity against blood-stage malaria remains unknown. We infected γδ T-cell-deficient (TCRδ-KO) mice and control wild-type mice with Plasmodium bergh...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2010-11-16 00:00:00
abstract::Vascular flow through tissues is regulated via a number of homeostatic mechanisms. Localized control of tissue blood flow, or autoregulation, is a key factor in regulating tissue perfusion and oxygenation. We show here that the net balance between two hypoxia-inducible factor (HIF) transcription factor isoforms, HIF-1...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1996-12-10 00:00:00
abstract::Prediction of the native tertiary structure of a globular protein from the primary sequence will require a potential energy model that can discriminate all nonnative structures from the native structure(s). A successful model must distinguish not only alternate structures that are very nonnative but also alternate str...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1995-01-31 00:00:00
abstract::We describe a molecular resistance biomarker to gefitinib, epithelial membrane protein-1 (EMP-1). Gefitinib is a small-molecule inhibitor that competes for the ATP-binding site on EGF receptor (EGFR) and has been approved for patients with advanced lung cancers. Treatment with gefitinib has resulted in clinical benefi...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2005-08-16 00:00:00
abstract::Blocking CD28-B7 T-cell costimulation by systemic administration of CTLA4Ig, a fusion protein which binds B7 molecules on the surface of antigen-presenting cells, prevents rejection and induces tolerance in experimental acute allograft rejection models. We tested the effect of CTLA4Ig therapy on the process of chronic...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1996-10-29 00:00:00
abstract::Antarctic ozone depletion is associated with enhanced chlorine from anthropogenic chlorofluorocarbons and heterogeneous chemistry under cold conditions. The deep Antarctic "hole" contrasts with the generally weaker depletions observed in the warmer Arctic. An unusually cold Arctic stratospheric season occurred in 2011...
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.1319307111
更新日期:2014-04-29 00:00:00