title: Characterization of the PRMT gene family in rice reveals conservation of arginine methylation.
abstract: Post-translational methylation of arginine residues profoundly affects the structure and functions of protein and, hence, implicated in a myriad of essential cellular processes such as signal transduction, mRNA splicing and transcriptional regulation. Protein arginine methyltransferases (PRMTs), the enzymes catalyzing arginine methylation have been extensively studied in animals, yeast and, to some extent, in model plant Arabidopsis thaliana. Eight genes coding for the PRMTs were identified in Oryza sativa, previously. Here, we report that these genes show distinct expression patterns in various parts of the plant. In vivo targeting experiment demonstrated that GFP-tagged OsPRMT1, OsPRMT5 and OsPRMT10 were localized to both the cytoplasm and nucleus, whereas OsPRMT6a and OsPRMT6b were predominantly localized to the nucleus. OsPRMT1, OsPRMT4, OsPRMT5, OsPRMT6a, OsPRMT6b and OsPRMT10 exhibited in vitro arginine methyltransferase activity against myelin basic protein, glycine-arginine-rich domain of fibrillarin and calf thymus core histones. Furthermore, they depicted specificities for the arginine residues in histones H3 and H4 and were classified into type I and Type II PRMTs, based on the formation of type of dimethylarginine in the substrate proteins. The two homologs of OsPRMT6 showed direct interaction in vitro and further titrating different amounts of these proteins in the methyltransferase assay revealed that OsPRMT6a inhibits the methyltransferase activity of OsPRMT6b, probably, by the formation of heterodimer. The identification and characterization of PRMTs in rice suggests the conservation of arginine methylation in monocots and hold promise for gaining further insight into regulation of plant development.
authors.affiliation: State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Ayaz
authors.initials: A
authors.lastname: Ahmad
authors.forename: Yuzhu
authors.initials: Y
authors.lastname: Dong
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Cao
mesh_terms: D001120:Arginine / Q000378:metabolism*; D017124:Conserved Sequence / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics*; D006657:Histones / Q000378:metabolism; D008745:Methylation; D005810:Multigene Family / Q000235:genetics*; D012275:Oryza / Q000201:enzymology* / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics; D011485:Protein Binding / Q000235:genetics; D021381:Protein Transport; D011484:Protein-Arginine N-Methyltransferases / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000201:enzymology; D013379:Substrate Specificity
chemical_list: D006657:Histones; D010940:Plant Proteins; D001120:Arginine; D011484:Protein-Arginine N-Methyltransferases