DNA 聚合酶 β 在 DNA 修复作用中的分子机制

MOLECULAR MECHANISM OF DNA pol β IN DNA REPAIR

利用肝癌与正常肝细胞ＤＮＡｐｏｌβ（β酶）活力存在的差别，观察到γ射线照射对β酶活力无明显影响，肝癌细胞的β酶活力仍明显高于正常肝细胞，表明肝癌对照射ＤＮＡ损伤修复合成能力比正常强，其修复作用机制，经用免疫组化和胞浆斑点杂交法研究，显示肝癌细胞β酶活力的增高是由于基因过度表达及其转录（ｍＲＮＡ）水平的增强有关。

The difference of DNA pol β activity between hepatoma and hepatocytes was used to observe no obvious influence on their activity after γ irradiation The pol β activity of hepatoma was still greater than normal hepatocytes It showed that the repair synthesis ability to the iradiated DNA damage in hepatoma was greater than normal It was found that the molecular mechanism of pol β was that higher pol β activity in hepatoma was due to its gene over expression and higher transcription (mRNA) level by immunocytochemistry and cytoplasmic dot hybridization investigation