Probst H, Riedinger H J, Gekeler V
Physiologisch-chemisches Institut, Universität Tübingen, Federal Republic of Germany.
Exp Cell Res. 1989 Feb;180(2):563-8. doi: 10.1016/0014-4827(89)90084-0.
Labeling with bromodeoxyuridine and analysis by isopycnic banding for emergence of DNA-helices density-labeled in both strands (HH-DNA) were used to examine whether transient controlled hypoxia induces significant overreplication in the DNA of cultured Ehrlich ascites cells within a single cell cycle. Diverse situations of the hypoxic period (4-8 h) within the BrdUrd labeling time (8-16 h) were tested. If transversal of more than one complete cell cycle by very fast cycling individual cells was avoided by using short BrdUrd labeling periods or by addition of colcemid, HH-DNA was never detected. This indicates that hypoxia does not induce significant overreplication under the conditions chosen and, in particular, that the burst of replicon initiations occurring after reoxygenation of hypoxic cells principally is not due to overreplication.
用溴脱氧尿苷进行标记，并通过等密度梯度离心分析双链均被密度标记的DNA螺旋（HH-DNA）的出现情况，以此来检测短暂的可控性缺氧是否会在单个细胞周期内诱导培养的艾氏腹水癌细胞DNA发生显著的过度复制。测试了在溴脱氧尿苷标记时间（8-16小时）内缺氧期（4-8小时）的不同情况。如果通过使用短的溴脱氧尿苷标记期或添加秋水仙酰胺来避免非常快速循环的单个细胞跨越一个以上完整的细胞周期，就从未检测到HH-DNA。这表明在所选择的条件下，缺氧不会诱导显著的过度复制，特别是缺氧细胞复氧后发生的复制子起始爆发主要不是由于过度复制。
