Understanding and Targeting the DNA Repair Network in Cancer

描述（由申请人提供）：基因组不稳定性是癌细胞的特征。同源重组（HR）介导的DNA修复代表了一种无错误的修复机制，以保持基因组的完整性，并确保遗传信息的高保真传输。我的长期目标是建立一个成功的和可持续的独立研究计划，在使用基因组和蛋白质组学方法研究HR修复方面具有核心竞争力。在我的独立职业生涯中，我希望从事（1）基础研究，以了解HR介导的DNA修复及其在肿瘤发生中的功能障碍;（2）基于机制的转化研究，将HR修复的根本突破转化为癌症预防，诊断，诊断和治疗的临床应用。 我提出的研究的总体目标，这将奠定我的独立研究生涯的基础，是了解新的核功能的人Ago 2，在RNA干扰途径的核心蛋白，在HR修复和基因组维护。基于我的初步数据，我假设，在DNA损伤反应的背景下，通过微调的调节机制，通过翻译后修饰，可能通过ATM/ATR激酶依赖的磷酸化，人核Ago 2调节HR修复双链断裂招募DNA修复蛋白在损伤位点通过蛋白质-蛋白质相互作用。我将通过一个结合机制和功能研究的综合平台，通过追求3个具体目标来验证这一假设：（1）确定Ago 2作为HR修复中的新型调节剂的功能。(2)表征HR修复中DNA损伤诱导的Ago 2翻译后修饰。(3)确定Ago 2在防止基因组不稳定性和肿瘤发生中的核功能。这项研究意义重大，因为它挑战了目前人类Ago 2主要在细胞质中发挥作用的研究范式。本研究将阐明两种进化上保守的基因组防御机制，小调控RNA途径和DNA损伤反应途径，如何通过Ago 2蛋白的功能参与HR修复过程中的DNA损伤。

DESCRIPTION (provided by applicant): Genomic instability is a characteristic of cancer cells. Homologous recombination (HR)-mediated DNA repair represents an error-free repairing mechanism to maintain genomic integrity and ensure high-fidelity transmission of genetic information. My long-term goal is to establish a successful and sustainable independent research program with a core competency in the study of HR repair using genomic and proteomic approaches. In my independent career, I wish to pursue (1) fundamental studies to understand HR-mediated DNA repair and its dysfunction in tumorigenesis and (2) mechanism-based translational studies to translate fundamental breakthroughs in HR repair into clinical applications in cancer prevention, diagnosis, prognostication, and therapy. The overall objective of my proposed research, which will lay the foundation for my independent research career, is to understand the novel nuclear function of human Ago2, a core protein in RNA interference pathways, in HR repair and genome maintenance. Based on my preliminary data, I hypothesize that in the context of DNA damage response, via fine-tuned regulatory mechanisms by posttranslational modifications, potentially through ATM/ATR kinase-dependent phosphorylation, human nuclear Ago2 regulates HR repair of double-strand breaks by recruiting DNA repair proteins at damage sites via protein-protein interactions. I will test this hypothesis by pursuing 3 specific aims through an integrated platform that combines mechanistic and functional studies: (1) Determine the function of Ago2 as a novel regulator in HR repair. (2) Characterize posttranslational modifications of Ago2 induced by DNA damage in HR repair. (3) Determine the nuclear function of Ago2 in preventing genomic instability and tumorigenesis. The proposed research is significant because it challenges the current research paradigm that human Ago2 functions predominantly in the cytoplasm. This study will shed light on how 2 evolutionarily conserved genome defense mechanisms, the small regulatory RNA pathways and DNA damage response pathway, converge at DNA lesions in the process of HR repair via the functional involvement of Ago2 protein.