[
Nat Genet,
2009]
The global patterning of histone lysine methylation has been scrutinized over the years in an effort to uncover unique features indicative of chromatin function. A study in Caenorhabditis elegans now shows that nucleosomes covering exons and introns on active genes are differentially marked by H3K36 trimethylation, suggesting a new mode of communication between chromatin and pre-mRNA processing.