School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA.
Mol Biol Evol. 2020 Aug 1;37(8):2322-2331. doi: 10.1093/molbev/msaa088.
Gene duplication serves a critical role in evolutionary adaptation by providing genetic raw material to the genome. The evolution of duplicated genes may be influenced by epigenetic processes such as DNA methylation, which affects gene function in some taxa. However, the manner in which DNA methylation affects duplicated genes is not well understood. We studied duplicated genes in the honeybee Apis mellifera, an insect with a highly sophisticated social structure, to investigate whether DNA methylation was associated with gene duplication and genic evolution. We found that levels of gene body methylation were significantly lower in duplicate genes than in single-copy genes, implicating a possible role of DNA methylation in postduplication gene maintenance. Additionally, we discovered associations of gene body methylation with the location, length, and time since divergence of paralogous genes. We also found that divergence in DNA methylation was associated with divergence in gene expression in paralogs, although the relationship was not completely consistent with a direct link between DNA methylation and gene expression. Overall, our results provide further insight into genic methylation and how its association with duplicate genes might facilitate evolutionary processes and adaptation.
基因复制通过为基因组提供遗传物质原料，在进化适应中起着至关重要的作用。复制基因的进化可能受到表观遗传过程的影响，如 DNA 甲基化，它会影响某些分类群中的基因功能。然而，DNA 甲基化影响复制基因的方式还不是很清楚。我们研究了具有高度复杂社会结构的昆虫——蜜蜂（Apis mellifera）中的复制基因，以调查 DNA 甲基化是否与基因复制和基因进化有关。我们发现，基因体甲基化水平在复制基因中明显低于单拷贝基因，这暗示了 DNA 甲基化在复制后基因维持中的可能作用。此外，我们发现基因体甲基化与旁系同源基因的位置、长度和分化时间有关。我们还发现，DNA 甲基化的分化与旁系同源基因表达的分化有关，尽管这种关系并不完全与 DNA 甲基化与基因表达之间的直接联系一致。总的来说，我们的研究结果进一步深入了解了基因甲基化，以及它与复制基因的关联如何促进进化过程和适应。
