牛泡沫病毒转录激活因子Borf1影响细胞周期相关基因的表达  

The Transcription Activator of Bovine Foamy Virus,Borf1,Influences the Expressions of Cell Cycle Related Genes

作　　者：刘力[1] 李健[1] 乔文涛[1] 陈启民[1] 耿运琪[1] 

机构地区：[1]南开大学分子微生物与技术教育部重点实验室,天津300071

出　　处：《南开大学学报（自然科学版）》2009年第3期33-37,共5页Acta Scientiarum Naturalium Universitatis Nankaiensis

基　　金：国家基础科学研究项目(2005CB522903)

摘　　要：Borf1蛋白是牛泡沫病毒编码的转录激活因子,可影响其自身及病毒结构基因的表达。但目前对Borf1在宿主细胞周期上的作用还未见研究报道。通过建立人胚肾293稳定表达Borf1的细胞系来研究其对宿主细胞的影响表明,在细胞内稳定表达Borf1可显著引发细胞在G1/G0的阻滞,并且降低S期细胞的比例。用半定量RT-PCR分析发现,Borf1可在mRNA水平下调周期蛋白cyclin A2,cyclin B1和cyclin E的表达。蛋白水平检测进一步核实这一结果。因此,Borf1通过影响周期相关蛋白表达,在G2-M及G1-S限制位点上发挥作用,进而引发细胞G1期阻抑。Borf1 is a transcription activator encoded by bovine foamy virus genome, and can activate the transcriptions of its own gene as well as viral structural genes. However, the effect of Borf1 on the expressions of cell cycle related genes has not been exploited. In current study, a human embryonic kidney 293 cell stably expressing Borf1 gene was established and used for the detection of the effect of Borf1 on the endogenous gene expressions in host cells. The results revealed that stably expressing Borfl significantly caused G1/G0 arrest, and in the same time reduced S phase population. Semi-quantitative RT-PCR demonstrated that Borf1 down-regulated the mRNA levels of cyclin A2, cyclin B1 and cyclin El. Western blot analysis on these cell cycle related genes further confirmed the above results. Thus, Borf1 may cause G1 arrest by influencing the expressions of a number of cell cycle related genes which may play critical roles at the restriction points during G2-M and G1-S transition.

关 键 词：Borf1蛋白 转录激活 细胞周期 G1期阻滞 周期蛋白 

分 类 号：Q753[生物学—分子生物学]