title: Protein substrates of the arginine methyltransferase Hmt1 identified by proteome arrays.
abstract: Arginine methylation on nonhistone proteins is associated with a number of cellular processes including RNA splicing, protein localization, and the formation of protein complexes. In this manuscript, Saccharomyces cerevisiae proteome arrays carrying 4228 proteins were used with an antimethylarginine antibody to first identify 88 putatively arginine-methylated proteins. By treating the arrays with recombinant arginine methyltransferase Hmt1, 42 proteins were found to be possible substrates of this enzyme. Analysis of the putative arginine-methylated proteins revealed that they were predominantly nuclear or nucleolar in localization, consistent with the localization of Hmt1. Many are involved in known methylarginine-associated functions, such as RNA processing and ribonucleoprotein complex biogenesis, yet others are of newer classes, namely RNA/DNA helicases and tRNA-associated proteins. Using ex vivo methylation and MS/MS, a set of 12 proteins (Brr1, Dia4, Hts1, Mpp10, Mrd1, Nug1, Prp43, Rpa43, Rrp43, Spp381, Utp4, and Npl3), including the RNA helicase Prp43 and tRNA ligases Dia4 and Hts1, were all validated as Hmt1 substrates. Interestingly, the majority of these also had human orthologs, or family members, that have been documented elsewhere to carry arginine methylation. These results confirm arginine methylation as a widespread modification and Hmt1 as the major arginine methyltransferase in the S. cerevisiae cell.
authors.affiliation: Systems Biology Initiative, School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, Australia.
authors.forename: Jason K K
authors.initials: JK
authors.lastname: Low
authors.affiliation: Department of Genetics, Stanford University School of Medicine, Palo Alto, CA, USA.
authors.forename: Hogune
authors.initials: H
authors.lastname: Im
authors.affiliation: Systems Biology Initiative, School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, Australia.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Erce
authors.affiliation: Systems Biology Initiative, School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, Australia.
authors.forename: Gene
authors.initials: G
authors.lastname: Hart-Smith
authors.affiliation: Department of Genetics, Stanford University School of Medicine, Palo Alto, CA, USA.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Snyder
authors.affiliation: Systems Biology Initiative, School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, Australia.
authors.forename: Marc R
authors.initials: MR
authors.lastname: Wilkins
mesh_terms: D000595:Amino Acid Sequence; D001120:Arginine / Q000378:metabolism*; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D063990:Gene Ontology; D008745:Methylation; D058977:Molecular Sequence Annotation; D008969:Molecular Sequence Data; D040081:Protein Array Analysis; D025941:Protein Interaction Mapping; D011499:Protein Processing, Post-Translational; D011484:Protein-Arginine N-Methyltransferases / Q000235:genetics / Q000378:metabolism*; D020543:Proteome / Q000235:genetics / Q000378:metabolism*; D020365:RNA Helicases / Q000235:genetics / Q000378:metabolism; D012326:RNA Splicing; D012343:RNA, Transfer / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
chemical_list: D020543:Proteome; D016601:RNA-Binding Proteins; D011994:Recombinant Proteins; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D012343:RNA, Transfer; D001120:Arginine; C475182:HMT1 protein, S cerevisiae; D011484:Protein-Arginine N-Methyltransferases; D004265:DNA Helicases; D020365:RNA Helicases
keywords: Arginine methylation; Hmt1 methyltransferase; Post-translational modification; Proteome arrays; Saccharomyces cerevisiae