HIV-1 Tat蛋白对DNA修复基因及细胞周期相关基因表达的影响  

Effects of HIV-1 Tat protein on expression of DNA repair genes and cell cycle related genes

作　　者：孙薏[1] 周平坤[2] 匡红[1] 张聪[1] 呼永河[1] 冯怀志[1] 李硕[1] 徐勤枝[2] 陈健[1] 

机构地区：[1]解放军第452医院,四川成都610021 [2]军事医学科学院放射与辐射医学研究所,北京100850

出　　处：《西南国防医药》2009年第12期1161-1164,F0004,共5页Medical Journal of National Defending Forces in Southwest China

基　　金：国际原子能机构合作项目(12510/RO);国家自然科学基金项目(30400120)

摘　　要：目的:探讨HIV-1 Tat蛋白对DNA修复基因及细胞周期相关基因表达影响。方法:使用包含102个与DNA损伤修复和细胞周期相关的基因微阵列检测人横纹肌肉瘤细胞(TE671)及已转染tat基因的TE671细胞(TT2)基因表达谱的改变;使用半定量RT-PCR分析DNA-PKcs在mRNA水平表达;Western印迹法检测DNA-PKcs表达变化;荧光染色法检测电离辐射后细胞凋亡。结果:在基因芯片的检测中,发现与DNA损伤修复及细胞周期调控相关的6个基因CdC25C、KIF2C、CdC20、DNA-PKcs、CTS1、WEE1在转染tat基因的细胞中表达下调;DNA-PKcs的表达在表达Tat蛋白细胞中不论是在mRNA和蛋白水平均被抑制;接受电离辐射后,表达Tat蛋白的细胞凋亡增加。结论:HIV-1 Tat蛋白使细胞对电离辐射敏感,部分通过抑制DNA-PKcs表达来降低DNA双链断裂的修复能力,本研究为了解AIDS合并肿瘤患者对放射治疗敏感性提供了重要实验数据。Objective： To explore effects of HIV - I Tat protein on expression of DNA repair genes and cell cycle related genes. Methods ： A human rhabdomyosarcoma cell lines TE671 and TI＇2 cells transfected with tat gene of the HIV - 1 strain were employed in this study. Microarray, which contains the oligonueleotide probes corresponding to 102 human DNA repair genes and cell cycle - related genes, was used to analyze the changes of gene expression in above two cell lines. The DNA - PKcs expression on mRNA and protein level was analyzed by RT - PCR and Western blot, respectively;the extent of apoptosis induced by ionizing radiation in Tat - expressing cells was detected by fluorescence staining. Results： Microarray assay demonstrated that cell cycle related genes CdC25C, KIF2C, CdC20, DNA - PKes, CTS1 and WEE1 were down - regulated in Tat - expressing TI＇2 cells;DNA - PKcs expression was inhibited whether on mRNA or on protein level. Furthermore, the extent of apoptosis induced by ionizing radiation in Tat - expressing cells was significantly higher than that in control cells. Conclusion ： HIV - 1 Tat protein may sensitize cells to ionizing radiation via at least partially depressing DNA - PKcs expression to lower repair ability of a cell following DNA double - strand break. Dysregulated cell cycle checkpoint in Tat - expressing cells could provide new information to understand the radiation responsiveness of AIDS patients with cancer to radiotherapy.

关 键 词：HIV-1 TAT 寡居核苷酸芯片 电离辐射 基因表达 细胞周期 

分 类 号：R512.91[医药卫生—内科学]