The Polycomb protein Ezl1 mediates H3K9 and H3K27 methylation to repress transposable elements in Paramecium

Abstract

H3K9me3 and H3K27me3 chromatin silencing marks are usually deposited by different SET-domain proteins. Here the authors show that the Enhancer-of-zeste-like protein Ezl1, from the unicellular eukaryote Paramecium tetraurelia, catalyzes methylation of histone H3 in vitro and in vivo with an apparent specificity toward K9 and K27, and controls the repression of transposable elements.