Different patterns of gene body DNA methylation in ESC and EpiSC
Résumé
DNA methylation is an epigenetic mark usually associated with repression of expression. However, this has been mainly shown when DNA methylation is localized in the promoter regions (see also abstract from "Veillard et al". With the possibility to generate whole-genome methylomes, it has become evident that most DNA methylated regions were within gene body, but no consistent roles have been yet assigned to this type of methylation, at least in mammalian species. To get insight into this phenomenon, we have compared the whole-genome methylomes of two types of mouse pluripotent cell lines, ESCs and EpiSCs. These two types of cells are considered as representing two states of pluripotency, the naïve and primed state and they display a number of phenotypic and functional differences. At first glance, their methylome did not differ significantly, however, a closer examination reveals striking differences of methylation in 5'UTR and 3'UTR as well as CpG island enrichment. Our study aims at investigating the functional significance of these differences.