title: Histone H3 recognition and presentation by the WDR5 module of the MLL1 complex.
abstract: WDR5 is a core component of SET1-family complexes that achieve transcriptional activation via methylation of histone H3 on Nzeta of Lys4 (H3K4). The role of WDR5 in the MLL1 complex has recently been described as specific recognition of dimethyl-K4 in the context of a histone H3 amino terminus; WDR5 is essential for vertebrate development, Hox gene activation and global H3K4 trimethylation. We report the high-resolution X-ray structures of WDR5 in the unliganded form and complexed with histone H3 peptides having unmodified and mono-, di- and trimethylated K4, which together provide the first comprehensive analysis of methylated histone recognition by the ubiquitous WD40-repeat fold. Contrary to predictions, the structures reveal that WDR5 does not read out the methylation state of K4 directly, but instead serves to present the K4 side chain for further methylation by SET1-family complexes.
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Ruthenburg
authors.forename: Wooikoon
authors.initials: W
authors.lastname: Wang
authors.forename: Daina M
authors.initials: DM
authors.lastname: Graybosch
authors.forename: Haitao
authors.initials: H
authors.lastname: Li
authors.forename: C David
authors.initials: CD
authors.lastname: Allis
authors.forename: Dinshaw J
authors.initials: DJ
authors.lastname: Patel
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Verdine
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D018360:Crystallography, X-Ray; D020962:Heterotrimeric GTP-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D011495:Histone-Lysine N-Methyltransferase; D006657:Histones / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008745:Methylation; D008958:Models, Molecular; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes; D051788:Myeloid-Lymphoid Leukemia Protein / Q000737:chemistry / Q000378:metabolism; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation
chemical_list: D006657:Histones; D047908:Intracellular Signaling Peptides and Proteins; C497422:KMT2A protein, human; D046912:Multiprotein Complexes; D010455:Peptides; C502547:WDR5 protein, human; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase; D020962:Heterotrimeric GTP-Binding Proteins