Pfeifer G P, Drahovsky D
FEBS Lett. 1986 Oct 20;207(1):75-8. doi: 10.1016/0014-5793(86)80015-1.
Mammalian DNA-cytosine 5-methyltransferases methylate cytosines in deoxyinosine containing DNA polymers more rapidly than in other synthetic or naturally occurring DNAs. The initial methylation rate of poly(dI-dC) X poly(dI-dC) is about 10-times higher than that of poly-(dG-dC) X poly(dG-dC) or of the native Micrococcus luteus DNA. In competitive binding experiments, DNA methyltransferase has about 10-fold higher affinity for the dI-containing alternating DNA polymer than for poly(dG-dC) X poly(dG-dC). The observed high methyl accepting capacity of poly(dI-dC) X poly(dI-dC) may be a useful methodological advance to determine de novo DNA methyltransferase activity in extracts of mammalian cells.
哺乳动物DNA胞嘧啶5 - 甲基转移酶使含脱氧肌苷的DNA聚合物中的胞嘧啶甲基化的速度比其他合成或天然存在的DNA更快。聚（dI-dC）×聚（dI-dC）的初始甲基化速率比聚（dG-dC）×聚（dG-dC）或天然的藤黄微球菌DNA的初始甲基化速率高约10倍。在竞争性结合实验中，DNA甲基转移酶对含dI的交替DNA聚合物的亲和力比对聚（dG-dC）×聚（dG-dC）的亲和力高约10倍。观察到的聚（dI-dC）×聚（dI-dC）的高甲基接受能力可能是确定哺乳动物细胞提取物中从头DNA甲基转移酶活性的一项有用的方法学进展。
