小鼠完全生长卵母细胞耐受DNA双链断裂损伤的分子机制研究

项目名称： 小鼠完全生长卵母细胞耐受DNA双链断裂损伤的分子机制研究

项目编号： No.31501204

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 生物科学

项目作者： 林飞

作者单位： 南京大学

项目金额： 20万元

中文摘要： DNA损伤是细胞面临的常见威胁之一，当遭受严重DNA损伤时细胞将启动凋亡程序，维护基因组稳定性。我们的前期研究发现小鼠完全生长卵母细胞在遭受严重DSBs损伤时，不仅不发生凋亡，而且能够恢复减数分裂，表现为DNA损伤检验点缺失。这种特殊现象的分子机制尚不明确。本研究将全面检测严重DSBs卵母细胞凋亡分子事件的发生情况、完整分析DDR主要通路——p53通路的应答状况、研究GV期特殊染色质构象对卵母细胞凋亡发生的影响，以阐明完全生长卵母细胞耐受严重DSBs的分子机理。进一步分析GV期后卵母细胞的DNA损伤应答，确定GV期后DNA损伤检验点重建的时间。生殖细胞承担着遗传物质传递的重任，其基因组稳定性决定了个体生殖和物种繁衍的能力，因此对生殖细胞DNA损伤的研究具有重要理论和现实意义。本项目的研究结果将完善不同阶段卵母细胞DNA损伤应答的变化规律，对癌症放化疗影响女性生殖能力的研究具有借鉴作用。

中文关键词： 小鼠；卵母细胞；凋亡；DNA双链断裂损伤；p53通路

英文摘要： DNA damage is one of the most common insults that challenge cells. When the extent of DNA damage exceeded repair capacity of the cell, apoptosis will initiate to maintain the stability of the genome. Our previous results found that fully grown mouse oocyte with serious DSBs didn’t initiate apoptosis, and they did resume meiosis, which indicated the absence of DNA damage checkpoint. The molecular mechanism of this particular phenomenon has not been clarified. In this study, we will comprehensively check apoptosis events; completely analyze p53 pathway which is the major pathway in DDR and do research on the effects of special chromatin structure in GV stage on oocyte apoptosis, so as to clarify the molecular mechanism of tolerance of DSBs in fully grown oocyte. Further more, DNA damage response after GV stage in oocyte will also be studied to determine the time when DNA damage checkpoint is reestablished. Germ cells bear the responsibility of passing genetic material to next generation, so its genome stability determines the reproductive ability of individuals and species reproduction. Therefore the research on DNA damage in germ cells is of great important theoretical and practical significance. The results of this project will disclose the variation of DNA damage response in oocyte in different stages; it is meaningful to improve the basic theory of reproductive biology. At the time, it can be referenced for the research about the effect of cancer chemotherapy and radiotherapy on female reproductive capacity.

英文关键词： mouse;oocyte;apoptosis;DNA double-strand breaks ;p53 pathway