Repair of Damaged Chromosomes Mediated by the Bacterial RecN Protein

细菌 RecN 蛋白介导的受损染色体修复

• 批准号: 8694055
• 负责人: SHELLEY LUSETTI
• 金额: $ 26.28万
• 依托单位: NEW MEXICO STATE UNIVERSITY LAS CRUCES
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-05 至 2018-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8694055
• 关键词: ATP Hydrolysis; ATP phosphohydrolase; Affinity; Bacteria; Bacterial Genome; Binding; Biochemical; Biochemistry; Biological; Catalysis; Chromosomal Instability; Chromosomal Rearrangement; Chromosome Deletion; Chromosomes; Congenital Abnormality; DNA; DNA Binding; DNA Double Strand Break; DNA Repair; DNA Repair Pathway; DNA-dependent ATPase; Data; Double Strand Break Repair; Genetic; Genetic Recombination; Genetic Screening; Genome; Goals; Housekeeping; Housing; Hydrolysis; In Vitro; Investigation; Kinetics; Lead; Maintenance; Malignant Neoplasms; Mediating; Metabolism; Modeling; Molecular; Mutation; Nucleotides; Organism; Orthologous Gene; Pathway interactions; Physical condensation; Pilot Projects; Play; Point Mutation; Positioning Attribute; Premature aging syndrome; Process; Property; Protein Family; Proteins; Reaction; Rec A Recombinases; Research Proposals; Role; Sister Chromatid; Substrate Specificity; Tumor Suppressor Proteins; Work; biophysical properties; cohesin; cohesion; ds-DNA; in vitro activity; in vivo; member; mutant; nucleotide analog; public health relevance; recombinase; recombinational repair; reconstitution; repaired

DESCRIPTION (provided by applicant): The overall goal of this research proposal is to reveal the molecular function of RecN, a protein critical to the repair of DNA double-stranded breaks (DSBs) in bacteria. Bacterial RecN proteins share significant homology to the Structural Maintenance of Chromosomes (SMC) family of proteins. Eukaryotic SMC proteins have essential (although not fully understood) housekeeping and tumor suppressor roles in a variety of DNA metabolic processes such as chromosomal condensation, sister chromatid cohesion and recombinational DNA repair. Although extensive genetic evidence underscores the importance of RecN proteins to bacterial genome maintenance, there has been little substantive biochemical investigation into their function and, consequently, the specific reactions requiring RecN have not been identified. We have successfully identified several in vitro activities mediated by the RecN protein including a cohesin function and the stimulation of recombination. We are now positioned to decipher mechanistic details of RecN function in recombinational DNA repair pathways, utilizing a combination of biochemical, biophysical and biological approaches. This project has three specific aims. First, we will further characterize the biochemical and biophysical properties of the RecN protein related to substrate binding and catalysis. Next, we will determine the role of RecN in mediating recombinational repair by using both in vitro pathway reconstitution and genetic screens. And, finally, we will determine the contribution of multiple sequence motifs conserved in all bacterial RecN proteins and shared by eukaryotic SMC orthologs. We anticipate that the results from this work will provide valuable models for understanding the molecular role that eukaryotic SMC proteins play in genome maintenance.

描述（由申请人提供）：该研究建议的总体目标是揭示RECN的分子功能，RECN的分子功能是细菌中DNA双链断裂（DSB）至关重要的蛋白质。细菌RECN蛋白与染色体（SMC）蛋白质家族的结构维持具有重要同源性。真核SMC蛋白在多种DNA代谢过程中，例如染色体凝结，姐妹染色性剂和重组DNA修复中必不可少的（尽管尚未完全了解）管家和抑制肿瘤的作用。尽管广泛的遗传证据强调了RECN蛋白对细菌基因组维持的重要性，但对其功能的实质性生化研究很少，因此，尚未鉴定出需要RECN的特定反应。我们已经成功地鉴定了由RECN蛋白介导的几种体外活性，包括粘蛋白功能和刺激重组。现在，我们可以利用生化，生物物理和生物学方法的组合来分解重组DNA修复途径中RECN功能的机械细节。该项目具有三个特定的目标。首先，我们将进一步表征与底物结合和催化有关的RECN蛋白的生化和生物物理特性。接下来，我们将通过使用体外途径重建和遗传筛选来确定RECN在介导重组修复中的作用。最后，我们将确定在所有细菌RECN蛋白中保守的多个序列基序的贡献，并通过真核SMC直系同源物共享。我们预计这项工作的结果将为理解真核SMC蛋白在基因组维持中起的分子作用提供宝贵的模型。