Department of Biochemistry, University of Oxford, Oxford, U.K.
MRC London Institute of Molecular Biology, London, U.K.
Biochem Soc Trans. 2022 Jun 30;50(3):1179-1190. doi: 10.1042/BST20210725.
DNA methylation is an epigenetic modification with a very long evolutionary history. However, DNA methylation evolves surprisingly rapidly across eukaryotes. The genome-wide distribution of methylation diversifies rapidly in different lineages, and DNA methylation is lost altogether surprisingly frequently. The growing availability of genomic and epigenomic sequencing across organisms highlights this diversity but also illuminates potential factors that could explain why both the DNA methylation machinery and its genome-wide distribution evolve so rapidly. Key to this are new discoveries about the fitness costs associated with DNA methylation, and new theories about how the fundamental biochemical mechanisms of DNA methylation introduction and maintenance could explain how new genome-wide patterns of methylation evolve.
DNA 甲基化是一种具有非常悠久进化历史的表观遗传修饰。然而，在真核生物中，DNA 甲基化的进化速度惊人地快。甲基化在不同谱系中的全基因组分布迅速多样化，而且 DNA 甲基化的丧失也非常频繁。随着跨生物基因组和表观基因组测序的日益普及，这凸显了这种多样性，但也揭示了可能解释为什么 DNA 甲基化机制及其全基因组分布进化如此之快的潜在因素。关键是与 DNA 甲基化相关的适应成本的新发现，以及关于 DNA 甲基化引入和维持的基本生化机制如何解释新的全基因组甲基化模式进化的新理论。
