中文摘要：

目的利用反义阻断REV3基因表达的人胚肾上皮细胞（HEK293-M-REV3^-）检测其对紫外线（UVB）的敏感性及细胞动力学的改变，评价hREV3基因在紫外线诱发突变中的作用。方法体外培养HEK293-M-REV3^-细胞，利用MTT法检测hREV3缺陷细胞系对UVB的敏感性，采用流式细胞技术DNA含量分析法检测细胞周期及DNA倍体指数（DI值）的变化，计算增殖指数PI值。结果HEK293-M-REV3^-细胞系对UVB的IC50为47．97mJ／cm^2，其敏感性明显比对照细胞高，流式细胞技术检测结果显示，自发状态下HEK293-M-REV3^-细胞系的S期比例增加，UVB处理后细胞G2-M期延长，随着处理后培养时间的延长，细胞周期停滞现象更明显，细胞的PI相应的有所改变。结论阻断hREV3基因表达，细胞对紫外线等物质敏感性增加，提示REV3基因参与哺乳动物细胞易误性跨损伤修复，易引起突变形成，原因可能与细胞周期的改变有关，由于REV3基因的低表达，细胞不能跨越损伤而使细胞周期停滞于致突变物质作用敏感的S期或G2-M期，引起DNA复制叉停滞，最终引起的结果是细胞的凋亡或死亡。

英文摘要：

Objective To evaluate the roles of REV3 in mutagenesis of mammalian cell. Methods HEK293 - M - REV3^ - cell was cultured in vitro, HEK - 293 - M - REV3^ - cells were untreated or treated with DNA damaging agent UVB irradiation, followed by flow cytometry to determine the cell cycle distribution and proliferation index （PI）. MTT assay was used to detect the sensitivity of UVB. Results HEK293 - M - REV3^- cell line was more sensitive than control lines to UVB irradiation, the ICso was 47.97mJ/cm^2. This study revealed that suppression of REV3 delayed spontaneous S phase progression. When treated with UVB, HEK - 293 - M - REV3^- cells were arrested at G2 - M phase of the cell cycle and resulting in an increased PI. Following the extension of the period of cultivation, the phenomenon of standstill became more obvious, PI had changed relatively. Conclusion This study suggests that hREV3 gene participates in error- prone repair, and it＇s responsible for the mutagenesis, and the mutagenesis connection with the change of the cell cycle.