Mechanisms and Crosstalk of DNA Break Resection Pathways

DNA断裂切除途径的机制和串扰

• 批准号: 8973831
• 负责人: HENGYAO NIU
• 金额: $ 24.9万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8973831
• 关键词: Atomic Force Microscopy; Binding; Binding Proteins; Biochemical; Biochemical Genetics; Biochemistry; Cell Cycle; Chemicals; Chromosomal Breaks; Chromosomes; Complex; DNA; DNA Binding; DNA Damage; DNA Double Strand Break; DNA Repair; DNA Sequence Alteration; DNA damage checkpoint; Defect; Deposition; Disease; Double Strand Break Repair; Eukaryota; Excision; Exposure to; G1 Phase; Genetic; Genome; Health; Human; Ionizing radiation; Lead; Ligation; Malignant Neoplasms; Maps; Mediating; Mentors; Modeling; Molecular; Motor; Nonhomologous DNA End Joining; Pathway interactions; Phase; Process; Proteins; Rad51 recombinase; Radiation; Reaction; Regulation; Research; Research Design; Research Project Grants; Resected; Role; Saccharomyces cerevisiae; Surgical incisions; System; Tail; Testing; Training; Yeasts; attenuation; base; chromatin immunoprecipitation; cohort; homologous recombination; irradiation; mutant; nuclease; polypeptide; public health relevance; reconstitution; repaired; yeast two hybrid system

Project Summary Homologous recombination (HR) and non-homologous end joining (NHEJ) are conserved pathways for the repair of DNA double stranded breaks (DSBs) induced by ionizing radiation and genotoxic chemicals. HR utilizes a homologous template strand to repair damaged DNA in an error-free manner. NHEJ, which entails processing of the broken chromosome ends and their ligation, is often error-prone. HR is initiated by nucleolytic processing of the DNA break to yield 3' ssDNA tails for the recruitment of the repair machinery. Studies in the model eukaryote Saccharomyces cerevisiae have revealed multiple pathways of DNA break resection, two of which are responsible for long-range resection. DNA break processing is regulated during the cell cycle. Specifically, NHEJ proteins suppress it in G1, but this suppression is relieved during S and G2. In the K99 phase of this project, I will determine the mechanisms of polarity control and DNA end engagement during the end resection process. In the R00 phase, I will elucidate the functional crosstalk between the long-range resection paths that are dependent on Sgs1/Dna2 and Exo1 and will also examine how the restriction imposed by NHEJ proteins is overcome by DNA motor proteins in conjunction with the Mre11 complex. Given the remarkable degree of conservation of the DNA end resection mechanisms, the results from this project should provide a valuable experimental framework to guide similar endeavors in other eukaryotes, including humans.

项目摘要 同源重组（HR）和非同源末端连接（NHEJ）是保守的 通过电离引起的DNA双链断裂（DSB）修复DNA双链断裂（DSB）的途径 辐射和遗传毒性化学物质。人力资源利用同源模板链修复 以无错误的方式损坏DNA。 NHEJ，需要处理破损的处理 染色体末端及其连接通常容易出错。 HR是由核解度开始的 DNA断裂的处理以产生3'ssDNA尾巴以募集修复 机械。酿酒酵母的真核生糖果糖果的研究表明 DNA断裂切除的多个途径，其中两个是远程的原因 切除。在细胞周期中调节DNA断裂处理。具体来说，nhej 蛋白质在G1中抑制它，但是在S和G2期间可以缓解这种抑制。 在该项目的K99阶段，我将确定极性控制的机制和 DNA结束在结束切除过程中。在R00阶段，我将阐明 依赖于远程切除路径之间的功能串扰 SGS1/DNA2和EXO1，还将检查NHEJ施加的限制如何 DNA运动蛋白与MRE11复合物结合使用DNA运动蛋白可以克服蛋白质。 鉴于DNA终端切除机制的显着保存程度 该项目的结果应提供一个有价值的实验框架来指导 在包括人类在内的其他真核生物中类似的努力。