在RER+瘤细胞中的超变性和不匹配修复缺陷
R Parsons1, G M Li, M J Longley
1Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710.
Cell
|December 17, 1993
概括
复制错误 (RER+) 的结肠直肠瘤由于缺陷的DNA不匹配修复,突变率高出100倍. 这项研究确定了癌细胞中这种突变表型的生物化学基础.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 在瘤学瘤学.
背景情况:
- 微卫星序列改变在零星结直肠瘤和遗传性非多重性结直肠癌 (HNPCC) 中很常见.
- 这些变化与复制错误阳性 (RER+) 现型有关,但根本原因尚不清楚.
研究的目的:
- 研究RER+结直肠瘤细胞中微卫星不稳定的分子基础.
- 为了确定RER+细胞是否表现出DNA不匹配修复中的缺陷.
主要方法:
- 实验室试验用于测量RER+和RER-瘤细胞中 (CA) n重复的突变率.
- 不匹配修复试验使用微卫星和基基不匹配异重复体进行.
主要成果:
- 在RER+瘤细胞中,突变率至少是RER-细胞的100倍.
- 在RER+细胞中发现了链特异性DNA不匹配修复的严重缺陷,影响了早期修复步骤.
结论:
- RER+结肠直肠瘤具有真正的突变表型.
- 在DNA不匹配修复中发现的缺陷为微卫星不稳定提供了生化基础,可能会导致癌症发展中的其他突变 (转变和转变).
相关概念视频
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01:38Nucleotide Excision Repair
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