Detection of carcinogen-induced DNA breaks by nick translation in permeable cells.
Detection of carcinogen-induced DNA breaks by nick translation in permeable cells.
复制标题
通过通透性细胞中的切口平移检测致癌物诱导的 DNA 断裂。
DOI：
10.1016/0006-291x(83)90317-0
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发表时间：
1983
影响因子：
3.1
通讯作者：
H. Okamoto
中科院分区：
文献类型：
--
作者：
K. Nose;H. Okamoto
与E.用大肠杆菌DNA聚合酶I（pol. I）原位检测化学致癌物引起的DNA断裂。用不同剂量的N-甲基-N′-硝基-N-亚硝基胍（MNNG）处理的正常人成纤维细胞用溶血素透化，并在[3 H] dCTP和pol. I存在下进行切口平移。掺入的放射性随MNNG浓度的增加而增加，并与聚（ADP-核糖）合成酶活性成正比。其他DNA损伤剂如博来霉素或4-硝基喹啉1-氧化物也会导致切口平移速率增加。当MNNG处理过的细胞在不含MNNG的新鲜培养基中培养时，在可渗透细胞中切口平移速率的增加变得较少，并且这种减少通过添加阿非迪霉素或阿糖胞苷而被消除。缺口平移法可能是一种有用的手段，估计内在的DNA断裂与致癌物质处理的细胞。
A nick-translation reaction with E. coli DNA polymerase I (pol. I) was used to detect in situ DNA breaks produced by chemical carcinogens. Normal human fibroblasts treated with N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) in various doses were permeabilized with lysolecithin, and were nick translated in the presence of [3 H] dCTP and pol. I. The radioactivity incorporated increased with MNNG concentration, and was directly proportional to the poly (ADP-ribose) synthetase activity. Other DNA-damaging agents such as bleomycin or 4-nitroquinoline 1-oxide also caused the nick translation rate to increase. When MNNG-treated cells were cultured in fresh medium containing no MNNG, the increase in the rate of nick translation in permeable cells became less and this decrease was abolished by addition of aphidicolin or cytosine arabinoside. The nick translation method described here may be a useful means for estimating intrinsic DNA breaks in cells treated with carcinogens.