Demethylation of H3K27 regulates polycomb recruitment and H2A ubiquitination.
Methylation of histone H3 lysine 27 (H3K27) is a posttranslational modification that is highly correlated with genomic silencing. Here we show that human UTX, a member of the Jumonji C family of proteins, is a di- and trimethyl H3K27 demethylase. UTX occupies the promoters of HOX gene clusters and regulates their transcriptional output by modulating the recruitment of polycomb repressive complex 1 and the monoubiquitination of histone H2A. Moreover, UTX associates with mixed-lineage leukemia (MLL) 2/3 complexes, and during retinoic acid signaling events, the recruitment of the UTX complex to HOX genes results in H3K27 demethylation and a concomitant methylation of H3K4. Our results suggest a concerted mechanism for transcriptional activation in which cycles of H3K4 methylation by MLL2/3 are linked with the demethylation of H3K27 through UTX.
Pubmed ID: 17761849 RIS Download
Cell Differentiation | Cell Line | Cell Line, Tumor | DNA-Binding Proteins | Embryonic Stem Cells | Genes, Homeobox | Histone Demethylases | Histones | Humans | Lysine | Methylation | Multigene Family | Neoplasm Proteins | Nuclear Proteins | Polycomb-Group Proteins | Promoter Regions, Genetic | Protein Processing, Post-Translational | Recombinant Proteins | Repressor Proteins | Signal Transduction | Transcription, Genetic | Transcriptional Activation | Tretinoin | Ubiquitin