活性基因的DNA甲基化,也被称为基因体甲基化,存在于许多动物和植物基因组中。尽管如此,这种甲基化的转录和发育作用仍然知之甚少。这里,我们探索蜜蜂DNA甲基化的动态范围,基因体甲基化的模型生物。
我们的数据表明,在蜜蜂发育过程中,基因体内的CG甲基化在全球范围内波动。然而,这些变化不会引起基因表达改变。有趣的是,尽管发生了全球性的变化,完整基因或外显子的组织特异性CG甲基化模式很少见,暗示发育过程中基因甲基化的稳健维持。此外,我们表明CG甲基化维持在体细胞中波动,同时在精子细胞中达到最大保真度。最后,与普遍存在的CG甲基化不同,我们发现非CG甲基化,特别是在蜜蜂头,类似于哺乳动物脑组织的甲基化。
基于这些结果,我们认为,如果将基因体CG甲基化保持在足以维持功能的水平,则可以在发育过程中振荡。此外,我们的数据表明,非CG甲基化增强是动物神经系统的保守调节因子.
DNA methylation of active genes, also known as gene body methylation, is found in many animal and plant genomes. Despite this, the transcriptional and developmental role of such methylation remains poorly understood. Here, we explore the dynamic range of DNA methylation in honey bee, a model organism for gene body methylation.
Our data show that CG methylation in gene bodies globally fluctuates during honey bee development. However, these changes cause no gene expression alterations. Intriguingly, despite the global alterations, tissue-specific CG methylation patterns of complete genes or exons are rare, implying robust maintenance of genic methylation during development. Additionally, we show that CG methylation maintenance fluctuates in somatic cells, while reaching maximum fidelity in sperm cells. Finally, unlike universally present CG methylation, we discovered non-CG methylation specifically in bee heads that resembles such methylation in mammalian brain tissue.
Based on these results, we propose that gene body CG methylation can oscillate during development if it is kept to a level adequate to preserve function. Additionally, our data suggest that heightened non-CG methylation is a conserved regulator of animal nervous systems.