XRCC1在MMS致人细胞DNA单链断裂修复中的作用

Role of XRCC1 in DNA Single-strand Break Repair in Human Bronchial Epithelial Cells

【目的】阐明人X线修复交叉互补基因1(XRCC1)在人支气管上皮细胞DNA单链断裂修复(SSBR)中的作用。【方法】以XRCC1蛋白缺陷细胞株为模型,用标准断裂剂甲基磺酸甲酯(MMS)染毒,检测细胞存活、微核形成、彗星实验及细胞周期变化等方法测定细胞遗传毒性。【结果】XRCC1蛋白水平的降低使细胞对DNA损伤剂的杀细胞效应敏感度增加、微核形成增加、DNA单链损伤修复能力降低以及引起明显的细胞周期阻滞。【结论】结果提示XRCC1基因在DNA单链损伤修复及基因组稳定性方面起着重要的作用。

[ Objective] To elucidate the role of X-ray repair cross complementing group 1 （XRCC1） in SSB repair （SSBR） in human bronchial epithelial cells. [Methods] On the basis of XRCCl-defective cell model through RNA interference, alkylating agent methyl methanesulfonate （MMS） was used to act on the cell. MTT assay, micronuclei formation, comet assay and cell cycle change were performed respectively to detect the genotoxicity of MMS. [ Results ] A reduction in XRCC 1 protein levels resulted in hypersensitivity to the cell killing effects of MMS, enhanced formation of micronuclei, decreased SSBR capacity and delay in cell cycle progression following exposure to MMS. [ Conclusion ] The results demonstrate XRCC1 is required for efficient SSBR and genomic stability inhuman cells.