5-Bromodeoxyuridine-dependent increase in sister chromatid exchange formation in Bloom's syndrome is associated with reduction in topoisomerase II activity.
5-Bromodeoxyuridine-dependent increase in sister chromatid exchange formation in Bloom's syndrome is associated with reduction in topoisomerase II activity.
复制标题
布卢姆综合征中 5-溴脱氧尿苷依赖性姐妹染色单体交换形成的增加与拓扑异构酶 II 活性的降低有关。
DOI：
10.1016/0014-4827(87)90242-4
复制
发表时间：
1987
影响因子：
3.7
通讯作者：
Latt,SA
中科院分区：
文献类型：
--
作者：
Heartlein,MW;Tsuji,H;Latt,SA
Bloom's syndrome is characterized by a high sister chromatid exchange (SCE) frequency, the basis for which is not yet understood. Immunofluorescent detection of SCE formation in dermal fibroblasts was employed over a wide range of 5-bromodeoxyuridine (BrdU) substitution into template DNA to show that this SCE elevation reflects both an increased baseline SCE frequency and an exaggerated increment in SCE formation as BrdU substitution increases. The impact of BrdU on SCE formation in Bloom's syndrome is paralleled by its ability to reduce the activity in nuclear extracts of topoisomerase II, an enzyme important for DNA replication and interchange. The extractable topoisomerase II activity of Bloom's syndrome fibroblasts, as measured by unknotting of page P4 DNA, is much more strongly inhibited by cell growth in medium containing BrdU than is that of normal fibroblasts. The results are consistent with the hypothesis that much of the BrdU-dependent component of SCE formation in Bloom's syndrome may be mediated by an effect of BrdU substitution of template DNA on topoisomerase II activity.
