Dixon Groves B, Bay Line K, Matz Mikhail V
Institute for Cell and Molecular Biology, University of Texas Austin, Austin, USA.
BMC Genomics. 2014 Dec 15;15(1):1109. doi: 10.1186/1471-2164-15-1109.
In invertebrates, genes belonging to dynamically regulated functional categories appear to be less methylated than "housekeeping" genes, suggesting that DNA methylation may modulate gene expression plasticity. To date, however, experimental evidence to support this hypothesis across different natural habitats has been lacking.
Gene expression profiles were generated from 30 pairs of genetically identical fragments of coral Acropora millepora reciprocally transplanted between distinct natural habitats for 3 months. Gene expression was analyzed in the context of normalized CpG content, a well-established signature of historical germline DNA methylation. Genes with weak methylation signatures were more likely to demonstrate differential expression based on both transplant environment and population of origin than genes with strong methylation signatures. Moreover, the magnitude of expression differences due to environment and population were greater for genes with weak methylation signatures.
Our results support a connection between differential germline methylation and gene expression flexibility across environments and populations. Studies of phylogenetically basal invertebrates such as corals will further elucidate the fundamental functional aspects of gene body methylation in Metazoa.
在无脊椎动物中，属于动态调节功能类别的基因似乎比“管家”基因甲基化程度更低，这表明DNA甲基化可能调节基因表达可塑性。然而，迄今为止，缺乏支持这一假设的跨不同自然栖息地的实验证据。
从30对基因相同的珊瑚鹿角珊瑚片段中生成基因表达谱，这些片段在不同的自然栖息地之间相互移植3个月。在标准化的CpG含量背景下分析基因表达，CpG含量是历史种系DNA甲基化的一个公认特征。与甲基化特征强的基因相比，甲基化特征弱的基因更有可能基于移植环境和起源群体表现出差异表达。此外，甲基化特征弱的基因因环境和群体导致的表达差异幅度更大。
我们的结果支持种系甲基化差异与跨环境和群体的基因表达灵活性之间的联系。对珊瑚等系统发育基础无脊椎动物的研究将进一步阐明后生动物基因体甲基化的基本功能方面。
