Fig. 3.

H3K36me2/3 represses cryptic transcription in yeast and human cells by recruiting different repressive chromatin modifiers. In yeast, H3K36me2 and H3K36me3 allosterically activate the Rpd3S HDAC complex to deacetylate chromatin and repress transcription initiation from gene bodies. In Drosophila, H3K36 is dispensable for repression of cryptic transcription. However, H3K36R Drosophila cells display increased global levels of H4 acetylation. H3K36me might therefore recruit or activate an HDAC in Drosophila similar as in yeast but this remains to be determined. In human cells, H3K36me3 has been reported to recruit DNMT3B leading the establishment of repressive DNA methylation in active gene bodies which inhibits cryptic transcription