Gavery Mackenzie R, Roberts Steven B
Brief Funct Genomics. 2014 May;13(3):217-22. doi: 10.1093/bfgp/elt054. Epub 2014 Jan 7.
The function of DNA methylation in species such as bivalves where the limited amount of DNA methylation is predominantly found in gene bodies remains unclear. An emerging possible explanation is that the role of gene body DNA methylation is dependent on gene function, a potential phenomenon that has arisen from selective pressure on lineage-specific life history traits. In genes contributing to phenotypes that benefit from increased plasticity, the absence of DNA methylation could contribute to stochastic transcriptional opportunities and increased transposable element activity. In genes where regulated control of activity is essential, DNA methylation may also play a role in targeted, predictable genome regulation. Here, we review the current knowledge concerning DNA methylation in bivalves and explore the putative role of DNA methylation in both an evolutionary and ecological context.
在双壳贝类等物种中，DNA甲基化的功能尚不清楚，因为有限的DNA甲基化主要存在于基因体中。一个新出现的可能解释是，基因体DNA甲基化的作用取决于基因功能，这是一种由对谱系特异性生活史特征的选择压力产生的潜在现象。在有助于从增加的可塑性中受益的表型的基因中，DNA甲基化的缺失可能有助于随机转录机会和增加转座元件活性。在活性调控至关重要的基因中，DNA甲基化也可能在靶向、可预测的基因组调控中发挥作用。在这里，我们综述了关于双壳贝类DNA甲基化的当前知识，并在进化和生态背景下探讨了DNA甲基化的假定作用。
