Methylation of the Arginine 2 in Histone H3 Controls Deposition of Lysine 4 Tri-Methylation

摘要

In a recent study, Kirmizis et al. demonstrated that H3R2 is methylated not only in mammals but also in Saccharomyces cerevisiae. By using a specific H3R2me2a antibody in a ChIP-on-Chip analysis the authors determined the distribution of the methylation throughout the yeast genome, finding an enrichment of H3R2me2a at all heterochromatic genes, at inactive euchromatic genes, and at the 3'-end of moderately transcribed genes.The presence of H3R2 methylation inversely correlates with the presence of H3K4 tri-methylation (H3K4me3) in all cases, reflecting the fact that H3R2 methylation disrupts the ability of the Set1- complex to methylate H3K4 by preventing the Set1-methyltransferase subunit Sppl from binding to to histone H3. These results show that H3R2 methylation controls the distribution of H3K4me3 and provide the first mechanistic insight into the function of arginine methylation on chromatin.