Investigating DNA double-strand break repair mechanisms in mammalian cells

研究哺乳动物细胞中 DNA 双链断裂修复机制

• 批准号: 10207031
• 负责人: Xiaohua Wu
• 金额: $ 44.38万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2026-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10207031
• 关键词: Address; Biological; Chromosomal Breaks; Chromosomal Rearrangement; DNA Damage; DNA Double Strand Break; Double Strand Break Repair; Equilibrium; Genetic Diseases; Genetic Recombination; Genomic Instability; Human Genome; Knowledge; Light; Malignant Neoplasms; Mammalian Cell; Mediating; Oncogenic; Other Genetics; Pathway interactions; Principal Investigator; Process; Repetitive Sequence; Reporter; Research; Role; Source; Stress; Structure; System; Variant; base; cancer cell; cancer genetics; coping; human disease; insight; prevent; repaired

Principal Investigator: Wu, Xiaohua Project Summary Gross chromosomal rearrangement (GCR) is a hallmark of cancer cells and the cause of structural variant formation in genetic disorders. DNA double-strand breaks (DSBs) are a major source to induce GCR, but the details on how the DSB repair process leads to genome instability in cancers and other genetic disorders remains elusive. Microhomologies are prevalent at chromosomal break junctions in cancer and other human diseases, suggesting that microhomology-mediated end joining (MMEJ) is one major player to mediate GCRs. Repetitive sequences are abundant, constituting about half of the human genome, which raises the question of how recombination between repetitive sequences is suppressed to prevent genome instability. In this proposal, we aim to investigate the mechanisms underlying MMEJ and repeat-mediated recombination in mammalian cells. We have established multiple EGFP-based DSB repair reporter systems, which enable us to study different DSB repair pathways in mammalian cells. By using newly established MMEJ reporters, we identified new players in the MMEJ pathway. We will investigate how these MMEJ players regulate MMEJ to balance its usage and its mutagenic consequences. We will also study the biological role of MMEJ in repairing replication- associated DSBs and in coping with replication and oncogenic stress, and address how MMEJ contributes to genome instability and the oncogenic process. Additionally, we will determine the mechanisms of repeat-mediated recombination in causing deletions and translocations, and study the role of heteroduplex rejection in preventing recombination among divergent repeats. These studies will generate much-needed new knowledge to fill the gap in our understanding of DSB repair mechanisms and the cause of genome instability that is associated with the oncogenic process and other genetic disorders.

主要研究者：吴晓华 项目摘要 大体染色体重排（GCR）是癌细胞的标志，并且染色体重排是癌细胞的特征。 遗传性疾病中结构变异形成的原因。DNA双链断裂 是诱导GCR的主要来源，但关于DSB修复过程如何导致 癌症和其他遗传疾病中的基因组不稳定性仍然难以捉摸。 微同源性在癌症和其他癌症中的染色体断裂连接处是普遍存在的。 人类疾病，表明微同源介导的末端连接（MMEJ）是一个主要的 玩家来调解GCR。重复序列是丰富的，构成了大约一半的 人类基因组，这提出了一个问题，如何重组之间的重复 序列被抑制以防止基因组不稳定。在本建议中，我们的目标是 研究MMEJ和重复介导的重组的潜在机制， 哺乳动物细胞 我们已经建立了多个基于EGFP的DSB修复报告系统， 使我们能够研究哺乳动物细胞中不同的DSB修复途径。通过使用newly 建立了MMEJ报告者，我们确定了MMEJ途径的新参与者。我们将 研究这些MMEJ球员如何调节MMEJ，以平衡其使用和诱变性 后果我们还将研究MMEJ在修复复制中的生物学作用- 相关的DSB和应对复制和致癌应激，并解决如何 MMEJ有助于基因组不稳定性和致癌过程。此外，我们将 确定重复介导的重组导致缺失的机制， 易位，并研究异源双链排斥在防止重组中的作用 在不同的重复中。这些研究将产生急需的新知识， 我们对DSB修复机制和基因组缺陷的原因的理解存在差距， 与致癌过程和其他遗传疾病相关的不稳定性。