Splicing enhances recruitment of methyltransferase HYPB/Setd2 and methylation of histone H3 lysine 36. Homo sapiens

Several lines of recent evidence support a role for chromatin in splicing regulation. Here we show that splicing can also contribute to histone modification, which implies a bidirectional communication between epigenetics and RNA processing. Genome-wide analysis of histone methylation in human cell lines and mouse primary T cells reveals that intron-containing genes are preferentially marked with H3K36me3 relative to intronless genes. In intron-containing genes, H3K36me3 marking is proportional to transcriptional activity, whereas in intronless genes H3K36me3 is always detected at much lower levels. Furthermore, splicing inhibition impairs recruitment of H3K36 methyltransferase HYPB/Setd2 and reduces H3K36me3, whereas splicing activation has the opposite effect. Moreover, the increase of H3K36me3 correlates with the length of the first intron, consistent with the view that splicing enhances H3 methylation. We propose that splicing is mechanistically coupled to recruitment of HYPB/Setd2 to elongating RNA Polymerase II. Overall design: This experiment proposes to profile genome-wide binding profiles by ChIP-seq (Illumina, 36 bp tags) of RNA polymerase II (one biological replicate), the histone modification H3K36me3 (2 replicates) and a reference control input sample (genomic DNA after reverse cross-link, one replicate) in a human H1299 lung carcinoma cell line *** Raw data not provided for Samples GSM766322-GSM766324.