title: Investigation of the methylation of Numb by the SET8 protein lysine methyltransferase.
abstract: It has been reported that the Numb protein is methylated at lysine 158 and 163 and that this methylation is introduced by the SET8 protein lysine methyltransferase [Dhami et al., (2013) Molecular Cell 50, 565-576]. We studied this methylation in vitro using peptide arrays and recombinant Numb protein as substrates. Numb peptides and protein were incubated with recombinant SET8 purified after expression in E. coli or human HEK293 cells. However, no methylation of Numb by SET8 was detectable. SET8 methylation of Histone H4 and p53 peptides and proteins, which were used as positive controls, was readily observed. While SET8 methylation of Numb in cells cannot be ruled out, based on our findings, more evidence is needed to support this claim. It appears likely that another not yet identified PKMT is responsible for the reported methylation of Numb in cells.
authors.affiliation: Institute of Biochemistry, Stuttgart University, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
authors.forename: Sara
authors.initials: S
authors.lastname: Weirich
authors.affiliation: Institute of Biochemistry, Stuttgart University, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
authors.forename: Denis
authors.initials: D
authors.lastname: Kusevic
authors.affiliation: Institute of Biochemistry, Stuttgart University, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
authors.forename: Srikanth
authors.initials: S
authors.lastname: Kudithipudi
authors.affiliation: Institute of Biochemistry, Stuttgart University, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
authors.forename: Albert
authors.initials: A
authors.lastname: Jeltsch
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D057809:HEK293 Cells; D011495:Histone-Lysine N-Methyltransferase / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008745:Methylation; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry; D011994:Recombinant Proteins; D016415:Sequence Alignment; D013379:Substrate Specificity
chemical_list: D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C113026:NUMB protein, human; D010446:Peptide Fragments; D011994:Recombinant Proteins; D011495:Histone-Lysine N-Methyltransferase; C470730:KMT5A protein, human