Function of RecO Protein in Recombination and Repair in E. coli

RecO 蛋白在大肠杆菌重组和修复中的功能

• 批准号: 9412816
• 负责人: Cynthia Luisi-DeLuca
• 金额: $ 50.5万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-08-15 至 2001-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9412816&HistoricalAwards=false
• 关键词: Function; RecO; Protein; Recombination; Repair

9412816 Abstract The bacterium E. coli provides a good model system for the study of genetic recombination. The ease with which it is maintained and genetically manipulated has allowed the isolation and analysis of a large number of recombination deficient mutants and the subsequent identification and analysis of the genes and respective gene products. Many of the genes involved in homologous recombination are also required for some aspect of DNA repair. There are at least three distinct recombination pathways termed RecBCD, RecE, and RecF which differ from each other with respect to the gene product(s) required. Both the RecBCD and RecF pathways function in wild type cells, and both are believed to require the recA gene product. At least twelve additional recombination genes are involved in some aspect of RecF pathway recombination, yet very little is known about the interaction between the RecF pathway gene products and how they function together in recombination. All RecF pathway mediated recombination requires the recO and recR gene products. In addition, both gene products are essential for DNA repair following UV irradiation or mitomycin C exposure. Purified RecO protein shares some biochemical activities with RecA protein including D-loop formation, and RecO can substitute for RecA in vivo, suggesting that the two proteins are functionally similar. The goal of this research is to further investigate the function of RecO protein in vivo, and to identify and characterize the biochemical properties associated with RecO in vitro that are relevant to RecO function in recombination and DNA repair. *** One aspect of DNA metabolism that is not well characterized at the molecular level is general recombination. Recombination mechanisms are essential to generate genetic diversity, to maintain cell viability after DNA damage, and to accurately segregate chromosomes during meiosis. %%%

9412816摘要大肠杆菌为研究基因重组提供了一个良好的模型系统。它的维护和基因操作的简单性使得大量重组缺陷突变的分离和分析以及随后对基因和相应基因产物的鉴定和分析成为可能。参与同源重组的许多基因在DNA修复的某些方面也是必需的。至少有三种不同的重组途径，称为RecBCD、Ress和RecF，它们对于所需的基因产物(S)是不同的。RecBCD和recf通路都在野生型细胞中发挥作用，都被认为需要recA基因产物。至少有12个额外的重组基因参与了RECF途径重组的某些方面，但对RECF途径基因产物之间的相互作用以及它们在重组过程中如何共同发挥作用还知之甚少。所有recf途径介导的重组都需要reco和recr基因产物。此外，这两种基因产物对于紫外线照射或丝裂霉素C暴露后的DNA修复都是必不可少的。纯化的Reco蛋白与RecA蛋白具有D-环形成等生化活性，在体内可替代RecA，提示两者在功能上相似。本研究的目的是进一步研究RECO蛋白在体内的功能，并在体外鉴定和鉴定与RECO重组和DNA修复功能相关的生化特性。*DNA代谢的一个方面在分子水平上没有得到很好的描述，那就是普遍的重组。重组机制对于产生遗传多样性，在DNA损伤后保持细胞活力，以及在减数分裂过程中准确分离染色体是必不可少的。%%%