Structural analysis of a carcinogen-induced genomic rearrangement event.
Structural analysis of a carcinogen-induced genomic rearrangement event.
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致癌物诱导的基因组重排事件的结构分析。
DOI：
10.1073/pnas.89.3.942
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发表时间：
1992
影响因子：
11.1
通讯作者：
Emanuel,BS
中科院分区：
文献类型：
--
作者：
Barr,FG;Davis,RJ;Eichenfield,L;Emanuel,BS
我们探索了仓鼠成纤维细胞培养系统中基因组重排的机制，其中通过化学致癌剂处理诱导内源性胸苷激酶基因5'端重排。克隆并测序了一个重排断点周围的野生型区域。利用该序列信息，通过逆聚合酶链式反应从相应的重排细胞系中克隆致癌物诱导的重排。断点片段测序后，通过未重排 DNA 的第二次反向聚合酶链反应分离野生型重排伴侣 (RP15)。将重排断点的序列与野生型 RP15 和 5' 胸苷激酶基因区域进行比较，发现断点处有短重复，以及每个重排伙伴中附近富含 A + T 的区域。脉冲场电泳分析表明，这种重排是 35 KB 的间质缺失。对未重排的亲代细胞中的 RP15 区域进行 Southern 印迹分析，显示出一个去甲基化的 CpG 岛和一个与重排删除的区域中的断点相邻的 DNase I 超敏位点复合物。因此，这些研究揭示了重排断点附近有趣的序列和染色质特征，并表明核组织在致癌物诱导的基因组重排机制中的作用。
We have explored the mechanism of genomic rearrangement in a hamster fibroblast cell culture system in which rearrangements are induced 5' to the endogenous thymidine kinase gene by chemical carcinogen treatment. The wild-type region around one rearrangement breakpoint was cloned and sequenced. With this sequence information, the carcinogen-induced rearrangement was cloned from the corresponding rearranged cell line by the inverse polymerase chain reaction. After the breakpoint fragment was sequenced, the wild-type rearrangement partner (RP15) was isolated by a second inverse polymerase chain reaction of unrearranged DNA. Comparison of the sequence of the rearrangement breakpoint with the wild-type RP15 and 5' thymidine kinase gene regions revealed short repeats directly at the breakpoint, as well as nearby A + T-rich regions in each rearrangement partner. Pulsed-field electrophoresis analysis demonstrated that this rearrangement is an interstitial deletion of 35 kilobases. Southern blot analysis of the RP15 region in unrearranged parental cells showed a demethylated CpG island and a complex of DNase I-hypersensitive sites adjacent to the breakpoint in the region deleted by the rearrangement. Therefore, these studies reveal interesting sequence and chromatin features near the rearrangement breakpoints and suggest a role for nuclear organization in the mechanism of carcinogen-induced genomic rearrangement.