Endogenous retroviruses (ERVs) are widely dispersed in mammalian genomes, and are silenced in somatic cells by DNA methylation. Here, an ERV silencing pathway independent of DNA methylation is shown to operate in embryonic stem cells. The pathway involves the histone H3K9 methyltransferase ESET and might be important for ERV silencing during the stages in embryogenesis when DNA methylation is reprogrammed.
- Toshiyuki Matsui
- Danny Leung
- Yoichi Shinkai