DNMT1-Interacting RNAs Block Gene-Specific DNA Methylation
5-methylcytosine is found in the context of paired symmetrical methylation of a CpG site. In normal somatic cells, most CpG sites are heavily methylated, while CpG islands (sites of CpG clusters) in germ-line tissues and located near promoters, remain unmethylated thus allowing gene expression to occur. When a CpG island in the promoter region of a gene is methylated, expression of the gene is repressed. The addition of methyl groups is controlled at several different levels in cells and is [more…]
