Abstract

5-Methyl-2'-deoxycytidine (mC) at CpG sites plays a key role in the epigenetic gene regulation, cell differentiation, and carcinogenesis. Despite the importance of mC for normal cell function, CpG dinucleotides are known as mutagenesis hotspots. Deamination of mC yields T, causing C→T transitions. However, several recent studies demonstrated the effect of epigenetic modifications of C on the fidelity and efficiency of DNA polymerases and excision repair enzymes. The review summarizes the available data that indicate the existence of deamination-independent mechanisms of mutagenesis at CpG sites.

中文翻译：

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复制和修复过程中 mCpG 位点突变的替代机制

摘要

CpG 位点的 5-甲基-2'-脱氧胞苷 (mC) 在表观遗传基因调控、细胞分化和癌发生中发挥着关键作用。尽管 mC 对正常细胞功能很重要，但 CpG 二核苷酸被称为诱变热点。mC 脱氨基产生 T，引起 C→T 转变。然而，最近的几项研究证明了 C 表观遗传修饰对 DNA 聚合酶和切除修复酶的保真度和效率的影响。该综述总结了现有数据，表明 CpG 位点存在不依赖脱氨基的诱变机制。