Twists and turns of DNA methylation

摘要

DNA methylation, the post-replicative transfer of a methyl group to the C5 position of cy-tosine bases, was the first epi-genetic modification identified and has been intensively studied for more than half a century. By now it is clear that Dnmtl, the major eukaryotic DNA methyl-transferase, faithfully maintains genome-wide methylation patterns and plays an essential role in the epigenetic network controlling gene expression and genome stability during development. However, the molecular mechanisms that ultimately control DNA methylation still remain elusive.