多种环境刺激因素均可诱导氧化应激，从而导致DNA双链断裂损伤和蛋白质氧化损伤。分子伴侣Hsp90是蛋白质质量控制的重要分子，其多种底物蛋白与DNA双链损伤修复通路密切相关。MRE11-RAD50-NBS1（MRN）蛋白复合物是DNA双链断裂损伤修复通路的重要始动因子，但氧化应激下Hsp90对其协同调控机制亟待阐明。本课题组前期定量蛋白质组学结果表明：Hsp90α敲除株伴随MRN蛋白水平下降，氧化应激诱导的DNA双链断裂损伤加重。因此，本课题将MRN复合物作为底物蛋白，以CRISPR-Cas9技术建立Hsp90敲除及表达Hsp90ATPase 突变体细胞株，应用凝胶迁移实验和ChIP-seq检测MRN复合物的活性。从影响Hsp90 分子伴侣功能的四要素：量、修饰状态、共伴侣蛋白、ATPase 活性，阐明氧化应激中Hsp90 对MRN蛋白复合物相关DNA双链断裂损伤修复通路中的调控作用。

Environmental stimuli induce oxidative stress and directly lead to DNA double strand breaks (DSBs) and protein oxidative damage.Hsp90 is vital to keep the protein homeostasis, and many client proteins of Hsp90 are the key molecules, which are critical for DSBs repair. MRE11-RAD50-NBS1 (MRN) complex is the important initial sensor and adaptor for the DSBs repair procedure. Meanwhile, how Hsp90 assists the MRN related DSBs repair is still unknown. Our results indicate,Hsp90αis related to the decrease of MRN protein level, and exacerbates DSBs damage induced by oxidative stress. Hence, we will take MRE11/RAD50/NBS1 as the target, monitor the MRN activity by EMSA and ChIP-seq, and focus on the level, modification status, cochaperone, ATPase activity of Hsp90 to explore the role of Hsp90 in MRN related DSBs damage/repair induced by oxidative stress.