中文摘要：

脂质体转染法将野生型人DNA聚合酶beta（pol β）重组绿色荧光蛋白表达载体转染人中国仓鼠卵巢细胞系（CHO），经G418筛选得到稳定高表达人野生型pol β的CHO细胞．通过RT-PCR方法检测转染细胞pol β mRNA的表达水平，流式细胞仪测细胞周期，软琼脂实验测细胞恶性增殖能力，6-TG实验测细胞自发突变率，以探讨转染细胞的生物学特性．结果显示，转染细胞pol β的mRNA的表达较空载体转染细胞、对照细胞增加，细胞周期多被阻滞在S期，细胞软琼脂集落形成率增高，白发突变率增加，表明pol β的过表达与细胞周期的分布、细胞恶性增殖程度、遗传稳定性相关．

英文摘要：

A recombined enhanced green fluorescent protein（GFP） vector pEGFP- AC3 carrying wide type DNA pol β gene was transfected into CHO cells by lipotransfection, and the stable transfectants were screened by G418. Stable overexpression of pol β in CHO was confirmed by RT- PCR, and its biological characteristics were analyzed from cell cycle, spontaneous mutation and cell soft agar growth. Expression level of polβ in the transfected cell increased significantly than the controls. The cell cycle distribution changed and most cells remained at S phage, And there was significant change in soft agar growths. Its spontaneous mutation rate was higher than that of the control cells. Overexpression of wild type polβ has some effect on the cell cycle distribution, malignant proliferation ability and genetic stability of cells.