Dutta-Choudhury T A, Couri D, Stephens R E
Department of Pharmacology, Ohio State University College of Medicine, Columbus 43210.
Carcinogenesis. 1992 Jan;13(1):33-9. doi: 10.1093/carcin/13.1.33.
O6-Methylguanine-DNA methyltransferase (O6-MT) has been described as a DNA repair enzyme that reverses alkylation damage at the O6 position of guanine in DNA. We demonstrate that the concentration of this protein decreases immediately prior to DNA synthesis in cultured chick hepatocytes. If intracellular levels are experimentally depleted by treatment of cultures with O6-methylguanine, DNA synthesis occurs as an associated resultant. This effect is dose dependent and can be followed by discernible morphological changes of organoids in culture. Increased and altered growth caused by O6-methylguanine was quantified and was also found to be dose dependent. Therefore, O6-MT may play a role in the regulation of DNA synthesis.
O6-甲基鸟嘌呤-DNA甲基转移酶（O6-MT）被描述为一种DNA修复酶，可逆转DNA中鸟嘌呤O6位的烷基化损伤。我们证明，在培养的鸡肝细胞中，这种蛋白质的浓度在DNA合成之前立即降低。如果通过用O6-甲基鸟嘌呤处理培养物来实验性地耗尽细胞内水平，DNA合成就会作为相关结果发生。这种效应是剂量依赖性的，并且可以伴随着培养物中类器官明显的形态变化。由O6-甲基鸟嘌呤引起的生长增加和改变进行了定量，并且也发现是剂量依赖性的。因此，O6-MT可能在DNA合成的调节中起作用。
