缺陷的不匹配结合和在耐受DNA损伤的细胞中的突变表型
P Branch1, G Aquilina, M Bignami
1Imperial Cancer Research Fund, Clare Hall Laboratories, South Mimms, Herts, UK.
Nature
|April 15, 1993
概括
细胞可以通过失去DNA不匹配修复活动来对破坏DNA的化剂产生抵抗力. 这种缺陷允许对O6-甲基瓜因 (m6-G),一种细胞毒性DNA损伤的耐受性,并导致突变表型.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 修复DNA修复DNA的修复
背景情况:
- 化剂如N-甲基-N-氨酸尿素会导致DNA损伤,形成O6-甲基氨酸 (m6-G).
- 对这些药物的获得性耐药性与对m6-G的耐受性有关,如果不修复,则具有细胞毒性.
- DNA不匹配修复 (MMR) 对基因组忠实性至关重要,它可以纠正基因不匹配和某些DNA损伤.
研究的目的:
- 调查DNA不匹配修复在获得抗化剂耐药性的作用.
- 为了确定涉及处理细胞毒性DNA病变的特定DNA不匹配结合活性.
- 了解MMR缺陷,m6-G耐受性和突变表型之间的联系.
主要方法:
- 对抗N-甲基-N-酸尿素的人类和仓鼠细胞系的发展和表征.
- 对抗性细胞系中DNA不匹配结合活性的检测.
- 表型分析,包括突变体表型评估.
主要成果:
- 鉴定了耐受N-甲基-N-酸盐的细胞系.
- 证明这些抗性细胞系在特定的DNA不匹配结合活动中有缺陷.
- 表明这种G.T错配结合活动的丧失赋予了一个突变的表型.
结论:
- 在DNA不匹配修复中的缺陷,特别是GT不匹配的结合,有助于获得对化剂的耐药性.
- 这种DNA不匹配结合活性的丧失导致对细胞毒性DNA损伤的耐受性,如m6-G.
- 麻疹病毒缺乏导致突变表型,突出其在维持基因组稳定性中的作用.
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