摘要
目的:探讨X射线对G_1和G_2期细胞双链DNA断裂损伤修复的动力学影响。方法:采用3%多聚甲醛或70%乙醇固定受X射线放射细胞的M059J、M059K和Hela,用流式细胞仪分选G_1和G_2期Hela细胞,以脉冲场电泳分析双链DNA断裂修复动力学。结果:乙醇固定不影响X射线放射引起的双链DNA断裂修复动力学,可用于固定Hela细胞G_1和G_2期的分选,且G_2期细胞双链DNA断裂修复速率显著慢于G_1期细胞。结论:G_1和G_2期细胞中的双链DNA断裂可能采用不同的修复方式。G_1期细胞主要采用快速的末端连接修复方式,而G_2期细胞主要采用相对较慢的同源性重组修复方式。
Objective:To study DNA Double Stand Breaks(DSB) repair kinetics in X-ray irradiated G1 and G2 cells. Methods:X-ray irradiated M059J, M059K and Hela cells were fixed with 70% ethanol or 3% paraformaldehyde, and G1 and G2 Hela ceils were sorted by flow cytometry. DSB repair kinetics was analyzed by pulsed field gel electrophoresis. Results: No significant effects of DSB repair kinetics were found in ethanol fixed cells compared to their non-fixed counterpart, and ethanol fixed Hela cells were suitable for sorting G1 and G2 cells. Furthermore, a slower repair kinetics in G2 cells were found than in G1 cells. Conclusion:G1 and G2 phase cells might recruit distinct repair pathways to deal with X ray induced DSBs. DSBs in G1 cells might prefer to be repaired by nonhomologous end-joining(NHEJ) while DSBs in G2 cells might prefer to be repaired by homjol ogous recombination(HRR).
出处
《中国临床医学》
北大核心
2007年第6期895-899,共5页
Chinese Journal of Clinical Medicine
关键词
非同源性末端连接
同源性重组
双链DNA断裂
细胞周期
X射线放射
Nonhomologous end-joining (NHEJ)
Homologous recombination (HRR)
DNA double strand breaks (DSBs)
Cell cycle
Ionizing radiation.