title: Specificity analysis-based identification of new methylation targets of the SET7/9 protein lysine methyltransferase.
abstract: We applied peptide array methylation to determine an optimized target sequence for the SET7/9 (KMT7) protein lysine methyltransferase. Based on this, we identified 91 new peptide substrates from human proteins, many of them better than known substrates. We confirmed methylation of corresponding protein domains in vitro and in vivo with a high success rate for strongly methylated peptides and showed methylation of nine nonhistone proteins (AKA6, CENPC1, MeCP2, MINT, PPARBP, ZDH8, Cullin1, IRF1, and [weakly] TTK) and of H2A and H2B, which more than doubles the number of known SET7/9 targets. SET7/9 is inhibited by phosphorylation of histone and nonhistone substrate proteins. One lysine in the MINT protein is dimethylated in vitro and in vivo demonstrating that the product pattern created by SET7/9 depends on the amino acid sequence context of the target site.
authors.affiliation: Biochemistry Laboratory, School of Engineering and Science, Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany.
authors.forename: Arunkumar
authors.initials: A
authors.lastname: Dhayalan
authors.forename: Srikanth
authors.initials: S
authors.lastname: Kudithipudi
authors.forename: Philipp
authors.initials: P
authors.lastname: Rathert
authors.forename: Albert
authors.initials: A
authors.lastname: Jeltsch
mesh_terms: D000595:Amino Acid Sequence; D019295:Computational Biology / Q000379:methods*; D057809:HEK293 Cells; D011495:Histone-Lysine N-Methyltransferase / Q000378:metabolism*; D006657:Histones / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008745:Methylation; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D010766:Phosphorylation; D013379:Substrate Specificity
chemical_list: D006657:Histones; D010446:Peptide Fragments; D011495:Histone-Lysine N-Methyltransferase