甲基醇通过Rev1相关的滑动和错配变异单链DNA
bioRxiv : the preprint server for biology
|April 1, 2025
概括
甲基醇 (MG) 是一种反应性化物,通过破坏单链DNA,导致酵母中的DNA突变. 这种与癌症相关的突变性过程依赖于特定的DNA修复途径,并且当排毒受损时会升高.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 甲基醇 (MG) 是一种来自新陈代谢和外部来源的反应性化物.
- MG与生物分子发生反应,形成病变并导致癌症等疾病.
- 人们对MG的体内突变性和在基因组不稳定性中的作用知之甚少.
研究的目的:
- 在体内研究甲基酸盐 (MG) 对单链DNA (ssDNA) 的致变性.
- 阐明MG诱导的突变发生背后的机制.
- 评估MG相关突变在人类癌症中的相关性.
主要方法:
- 用酵母作为模型系统来研究诱导的ssDNA上的MG突变发生.
- 在glioxalase 1 (Glo1) 酶和化物灭剂 (aminoguanidine) 的存在和不存在下评估了MG突变发生.
- 研究了转化聚合酶Rev1在MG突变发生中的作用,并分析了突变丰富的瘤数据集.
主要成果:
- 在酵母中,MG强有力的致变sDNA,特别是在富含关氨酸的基因中.
- 在Glo1缺乏酵母中,MG突变显著增加,而aminoguanidine则降低.
- 链滑落和错配是关键机制,需要Rev1,而特定的MG诱导的突变在人类瘤中得到丰富.
结论:
- 甲基醇是一种直接的突变原体,通过ssDNA损伤引起基因组不稳定.
- 氧酶系统 (Glo1) 对于排毒MG和预防突变发生至关重要.
- 转基因诱导的突变与致癌相关,并可能导致各种癌症的突变负担.
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