Mre11/Rad50/Nbs1 Structural Biology for DNA Damage Responses

Mre11/Rad50/Nbs1 DNA 损伤反应的结构生物学

• 批准号: 9055648
• 负责人: PAUL RUSSELL
• 金额: $ 41.15万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-01 至 2020-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9055648
• 关键词: ATM Gene Mutation; ATP phosphohydrolase; Address; Advanced Development; Advanced Malignant Neoplasm; Antibodies; Binding; Binding Proteins; Biochemical; Biochemical Genetics; Biochemistry; Biological; Biological Assay; Biology; Cancer Etiology; Cell Death; Cells; Cellular biology; Chemicals; Chromosomal Instability; Chromosomes; Complex; Coupled; DNA; DNA Binding; DNA Damage; DNA Double Strand Break; DNA Integration; DNA Repair; DNA Repair Pathway; DNA replication fork; Defect; Development; Eukaryota; Fission Yeast; Funding; Future; Genetic; Genomic Instability; Health; Human; Hydrolysis; Immunodeficiency and Cancer; Inherited; Knowledge; Lead; Link; Malignant Neoplasms; Mediating; Medicine; Meiosis; Molecular; Molecular Conformation; Mutagenesis; Mutate; Mutation; Neurodegenerative Disorders; Nijmegen Breakage Syndrome; Nonhomologous DNA End Joining; Normal Cell; Outcome; Pathway interactions; Patients; Phenotype; Play; Predisposition; Process; Proteins; Radiation; Radiation Tolerance; Recruitment Activity; Research Project Grants; Resistance; Resolution; Roentgen Rays; Role; Signal Pathway; Signal Transduction; Structural Biochemistry; Structure; Structure-Activity Relationship; Technology; Telomere Maintenance; Testing; Therapeutic Intervention; United States National Institutes of Health; Work; Yeasts; ataxia telangiectasia mutated protein; ataxia-telangiectasia like disorder; base; cancer cell; cancer therapy; chemotherapy; design; endoexonuclease; endonuclease; genetic analysis; human disease; inhibitor/antagonist; insight; killings; microbial; mutant; nuclease; recombinational repair; repaired; response; small molecule; structural biology; success; telomere; tool; yeast genetics

 DESCRIPTION (provided by applicant): Defects in the Mre11-Rad50-Nbs1 (MRN) complex results in human disease including cancer, and severe DNA damage phenotypes in yeast. MRN, acting with CtIP, is essential for the repair of double- stranded DNA breaks (DSBs) by homologous recombinational repair (HRR), as well as acting in meiosis, antibody hypermutation, telomere maintenance, rescue of stalled replication forks, and DNA damage signaling through ATM kinase. Yet, the mechanistic basis for diverse MRN functions is poorly understood. We propose three Specific Aims to understand MRN, CtIP and ATM structural biochemistry, activities, conformations and interactions relevant for DSB repair and signaling. We will couple advanced biophysical technologies, including atomic-resolution crystal structures and small- angle X-ray scattering in solution, with mutagenesis, biochemistry and yeast genetic analyses. Our integrated approaches will test hypotheses that dynamic MRN conformations and macromolecular interfaces control biological responses at DSBs. In particular, our results will significantly advance knowledge of 1) Mre11 DNA-binding and nuclease mechanisms and their importance for DNA repair pathway choice and progression. 2) How Rad50 binds to DNA and uses its ATPase activity to both handoff DNA to Mre11 and allosterically regulate Mre11 nuclease activities. 3) A Rad50 patient mutation that will advance our understanding of therapeutically targetable Rad50 protein features. 4) Catalytic and non-catalytic roles of CtIP. 5) How MRN recruits and activates ATM at DSBs. Our latest Mre11 inhibitor results and work from others in the field suggest that MRN roles in DSB repair and signaling are viable targets for the development of advanced adjunct cancer therapies, which work by synthetic lethality with current radiation and chemotherapies along with weaknesses in other DNA repair or signaling pathways arising from either inhibitors or cancer-specific genetic defects. Thus, our integrated results will provide a molecular framework for understanding cancer etiologies from DNA repair defects and for the design of advanced cancer therapies targeted against specific MRN activities. Collectively, project results will connect MRN, CtIP and ATM to cellular outcomes and human disease-states by defining interactions, conformations and mechanisms critical for genetic integrity, cancer therapy resistance, and future cancer treatments.

 描述（由申请方提供）：Mre 11-Rad 50-Nbs 1（MRN）复合物中的缺陷导致人类疾病，包括癌症和酵母中的严重DNA损伤表型。与CtIP一起作用的MRN对于通过同源重组修复（HRR）修复双链DNA断裂（DSB）以及在减数分裂、抗体超突变、端粒维持、停滞复制叉的拯救和通过ATM激酶的DNA损伤信号传导中起作用是必不可少的。然而，各种MRN功能的机械基础知之甚少。我们提出了三个具体的目标，以了解MRN，CtIP和ATM的结构生物化学，活动，构象和相互作用相关的DSB修复和信号。我们将把先进的生物物理技术（包括原子分辨率晶体结构和溶液中的小角X射线散射）与突变、生物化学和酵母遗传分析结合起来。我们的综合方法将测试假设，动态MRN构象和大分子界面控制生物反应在DSBs。特别是，我们的研究结果将显着推进1）Mre 11 DNA结合和核酸酶机制及其对DNA修复途径选择和进展的重要性的认识。2)Rad 50如何与DNA结合并利用其ATP酶活性将DNA传递给Mre 11并变构调节Mre 11核酸酶活性。3)Rad 50患者突变将促进我们对治疗靶向Rad 50蛋白特征的理解。4)CtIP的催化和非催化作用。第五章） MRN如何在DSB招募和激活ATM。我们最新的Mre 11抑制剂结果和该领域其他人的工作表明，MRN在DSB修复和信号传导中的作用是开发高级辅助癌症疗法的可行靶点，该疗法通过与当前放疗和化疗的合成致死性沿着抑制剂或癌症特异性遗传缺陷引起的其他DNA修复或信号传导途径的弱点而起作用。因此，我们的综合结果将为理解DNA修复缺陷的癌症病因学和针对特定MRN活动的先进癌症疗法的设计提供分子框架。总的来说，项目结果将通过定义对遗传完整性、癌症治疗抗性和未来癌症治疗至关重要的相互作用、构象和机制，将MRN、CtIP和ATM与细胞结果和人类疾病状态联系起来。