低剂量电离辐射引起拓扑异构酶Ⅱα蛋白和mRNA的表达变化  

Effection of low dose ionizing radiation on expressions of DNA topoisomeraseIIα protein and mRNA.

作　　者：李华[1] 刘雯[2] 左伋[2] 

机构地区：[1]上海中医药大学生物教研室,201203 [2]复旦大学医学院细胞与遗传医学系,200032

出　　处：《中国优生与遗传杂志》2007年第1期20-22,共3页Chinese Journal of Birth Health & Heredity

基　　金：国家自然科学基金资助项目(30100037)

摘　　要：目的探讨低剂量电离辐射引起DNA拓扑异构酶IIα(TOPO IIα)蛋白质和mRNA表达变化规律。方法用W estern b lot和RT-PCR的方法分别检测Hela细胞在接受低剂量电离辐射后不同时间、不同剂量和多次辐射的累积后蛋白质和mRNA的变化。结果细胞受5Gy的照射时,TOPOⅡα蛋白的表达较对照在4h已开始下降,12h降为最低,16h已开始恢复,mRNA在4h开始下降,8h降为最低,12h开始恢复,较蛋白的变化早;细胞受不同剂量照射后12h,TOPOⅡα蛋白和mRNA的表达均较对照降低,且下降程度随剂量增加而增加,且具有次数累加效应。结论低剂量电离辐射引起TOPO IIα表达的变化具时间效应、剂量效应和多次累加效应,mRNA的变化早于蛋白质的变化。Objective： To explore change rules of expressions of DNA topoisomeraseⅡα protein and mRNA in Hela cells treated with low dose ionizing radiation. Methods： The kinetics of TOPOⅡα protein was measured by western blot, and that of mRNA was measured by RT - PCR. Results ： A profound and transient decrease of TOPOⅡα protein and mRNA after low dose γ irradiation were detected. The decrease of protein began at 4h after irradiation, reached the lowest level at 12h, and began to return at 16h. The decrease of mRNA began at 4h after irradiation, reached the lowest level at 8h, and began to return at 12h. Given low dose γ -rays, the levels of protein and mRNA decrased along with the increase of dose. The level of decrease after several times irradiation was higher than that after only one time. Conclusion ： The observation indicates that the decrease of TOPOⅡα protein and mRNA after γ - irradiation is time - dependent and dose - dependent, and the effect of low dose γ - irradiation can be accumulated.

关 键 词：低剂量电离辐射 拓扑异构酶Ⅱα 蛋白表达 MRNA表达 

分 类 号：Q345[生物学—遗传学]