芬科尼贫血路径修复了由菌素诱导的DNA跨链交叉链接
Maria Altshuller1, Xu He1, Elliot J MacKrell1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA.
bioRxiv : the preprint server for biology
|February 14, 2024
概括
肠道细菌毒素可利巴克丁 (colibactin) 导致与癌症相关的DNA链间交叉链 (ICLs). 我们的研究揭示了细胞如何使用Fanconi贫血路径和转化合成来修复这些ICL,为癌症进展提供了洞察力.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 科利巴克丁是人类肠道中的细菌基因毒素,有助于结直肠癌和炎症性肠病.
- 科利巴克会诱导DNA链间交叉链 (ICLs),阻碍DNA复制.
- 已知解决ICL的细胞机制,但它们在 colibactin 耐药性中的作用尚不清楚.
研究的目的:
- 为了研究大肠杆菌素诱导的ICLs的复制合修复.
- 阐明参与耐受 colibactin DNA 损伤的途径.
主要方法:
- 使用了Xenopus蛋提取物用于生物化学研究.
- 使用带有特定部位的 colibactin-ICL 的工程塑.
- 分析了复制分叉停滞,复制体动力学和DNA修复途径激活.
主要成果:
- 在 colibactin-ICLs 的复制停止触发了复制体分解和 Fanconi 贫血路径的激活.
- 芬科尼贫血途径解开了ICLs,产生了双链断裂和单向导.
- 通过Polη和Polκ-REV1-Polζ复合物的转化合成修复了单添加管,有时引入T>N突变.
结论:
- 这项研究提供了一个生物化学框架,以了解细胞对菌素诱导的DNA损伤的耐受性.
- 这些发现阐明了复制,ICL修复和转化合成之间的相互作用,以应对临床相关的基因毒素.
- 已识别的修复途径和相关突变为我们提供了有关菌素在癌症发展中的作用的见解.
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