Academy of Fundamental and Interdisciplinary Science, Harbin Institute of Technology, Harbin 150080, China.
Genomics. 2012 Jan;99(1):10-7. doi: 10.1016/j.ygeno.2011.10.004. Epub 2011 Oct 25.
DNA methylation changes in repetitive elements (REs) are associated with the regulation of gene transcription, embryonic development, differentiation and carcinogenesis. However, genome-wide analysis of DNA methylation of human REs is lacking. Here, we performed genome-wide methylation analysis of REs in nine repeat types in human embryonic stem cells (H1) and fetal fibroblasts (IMR90), and found that the potential for changes in the DNA methylation of REs was different among the nine repeat types and within different genomic regions. DNA methylation changes in the nine repeat types were related to the GC content and CpG density of the sequence contexts. The differentially methylated REs and targeted genes of different repeat types were associated with gene silencing in the transition from H1 to IMR90 cells. Our results suggest that a quarter of REs are involved in the reprogramming of DNA methylation which may play important epigenetic roles during cellular differentiation.
重复元件 (REs) 中的 DNA 甲基化变化与基因转录的调控、胚胎发育、分化和癌变有关。然而，人类重复元件的全基因组 DNA 甲基化分析仍有待研究。在这里，我们对人类胚胎干细胞 (H1) 和胎儿成纤维细胞 (IMR90) 中的九种重复类型的重复元件进行了全基因组甲基化分析，发现九种重复类型和不同基因组区域中重复元件的 DNA 甲基化变化潜力不同。九种重复类型的 DNA 甲基化变化与序列背景的 GC 含量和 CpG 密度有关。不同重复类型的差异甲基化重复元件和靶向基因与 H1 向 IMR90 细胞转化过程中的基因沉默有关。我们的研究结果表明，四分之一的重复元件参与了 DNA 甲基化的重编程，这可能在细胞分化过程中发挥重要的表观遗传作用。
