在基因组中的G-runs进化中反映的DNA损伤
1Institute of Chemical Biology and Fundamental Medicine of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia.
Vavilovskii zhurnal genetiki i selektsii
|January 15, 2026
概括
DNA氧化会损害遗传物质,其中8-oxoguanine (8-oxoG) 是一个关键的损伤. 这项研究揭示了瓜宁运行 (G-运行) 如何影响 prokaryotic 和人类基因组中的 8-oxoG 形成和突变发生.
科学领域:
- 遗传学和基因组学 遗传学和基因组学
- 分子生物学分子生物学
- DNA 修复和突变发生.
背景情况:
- DNA氧化是遗传损伤的一个重要来源.
- 8-oxoguanine (8-oxoG) 是一种主要的氧化损伤,导致G→T突变.
- 双链DNA的π系统促进了孔移动,局部化了5'-终端瓜运行 (G-运行) 的氧化损伤.
研究的目的:
- 为了研究G-run核酸背景对突变发生谱的体内影响.
- 分析 prokaryotic 和人类基因组中的G-run的特征.
- 探索G-run特性与8-oxoG形成/变异发生之间的关系.
主要方法:
- 在62个 prokaryotic 基因组和人类端粒到端粒基因组中对G-run 核酸背景的生物信息分析.
- 在长度和延长概率方面对G运行和聚氨酸运行 (A运行) 的比较分析.
- 检查与G运行相关的侧边核酸频率和突变模式.
主要成果:
- G-运行通常比A-运行更短,在原核生物中延长概率较低.
- 增加T频率的5'-侧面G-运行,特别是在有氧生物中,支持偏好的G→T替代.
- 人类基因组显示了双相G-run扩张和增加的5'-侧面C,与端粒重复中的潜在新型突变性过程有关.
结论:
- G-run 序列背景显著影响 8-oxoG 形成和 in vivo 突变发生.
- 这些发现与8oxoG诱导的G→T转换模型相一致,特别是在有氧生物中.
- 人类端粒G运行中独特的突变性模式表明未经特征的DNA聚合酶错误或修复机制.
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