Dynamics of BRCA1-Mediated Double-Strand Break Repair

BRCA1 介导的双链断裂修复动力学

• 批准号: 8990014
• 负责人: David Thomas Long
• 金额: $ 24.9万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-05-02 至 2017-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8990014
• 关键词: BRCA1 Mutation; BRCA1 gene; Bacteriophages; Biological Assay; Cells; Chromatin; Complex; DNA; DNA Damage; DNA Double Strand Break; DNA Repair; DNA analysis; DNA lesion; Development; Dissociation; Double Strand Break Repair; Eukaryotic Cell; Event; Excision; Foundations; Genetic Recombination; Genome Stability; Hereditary Breast Carcinoma; Hereditary Disease; Hypersensitivity; Image; Individual; Lead; Link; Malignant Neoplasms; Malignant neoplasm of ovary; Mechanics; Mediating; Mentors; Movement; Mutate; Pathway interactions; Patients; Phase; Play; Predisposition; Process; Proteins; Regulation; Role; S Phase; Signal Transduction; Sister Chromatid; Site; System; Techniques; Time; Tumor Suppressor Genes; Tumor Suppressor Proteins; Xenopus; clinically relevant; egg; homologous recombination; insight; malignant breast neoplasm; novel; repaired; research study; response; single molecule; tool; treatment strategy

Project Summary A variety of DNA lesions lead to the formation of DNA double-strand breaks (DSBs), either directly or as intermediates of repair. To counter the accumulation of DNA damage, eukaryotic cells employ a complicated network of pathways that promote damage recognition, checkpoint signaling, and DNA repair. Components of the DNA damage response network have been linked to various genetic disorders that are typified by hypersensitivity to DNA damaging agents and cancer predisposition. In particular, the breast cancer tumor suppressor BRCA1 has been described as a master regulator of genome stability due to its involvement in various aspects of the damage response. This proposal seeks to understand how BRCA1 regulates homologous recombination (HR) to promote error-free repair of DSBs. In S phase, the ends of a DSB are processed by the resection machinery to promote HR-mediated repair, which takes advantage of the newly replicated sister chromatid as a template for error-free repair. Having recently established that Xenopus egg extracts can recapitulate recombination-dependent repair of a DSB, this system will provide a powerful tool to elucidate the mechanism of BRCA1-mediated HR. To study the dynamic events of HR, a novel DSB repair system will be established that supports analysis by single-molecule imaging. New techniques have been developed that support real-time imaging in highly concentrated Xenopus egg extracts, providing a significant advantage over traditional single-molecule approaches that rely on purified components studied in isolation. Single-molecule imaging will be used to analyze BRCA1-dependent DSB repair in real time, providing a level of mechanistic insight not available with traditional ensemble approaches. In this way, the complex functions of BRCA1 can be dissected to determine how cells regulate different aspects of the DNA damage response.

项目总结