title: Alternative splicing yields protein arginine methyltransferase 1 isoforms with distinct activity, substrate specificity, and subcellular localization.
abstract: PRMT1 is the predominant member of a family of protein arginine methyltransferases (PRMTs) that have been implicated in various cellular processes, including transcription, RNA processing, and signal transduction. It was previously reported that the human PRMT1 pre-mRNA was alternatively spliced to yield three isoforms with distinct N-terminal sequences. Close inspection of the genomic organization in the 5'-end of the PRMT1 gene revealed that it can produce up to seven protein isoforms, all varying in their N-terminal domain. A detailed biochemical characterization of these variants revealed that unique N-terminal sequences can influence catalytic activity as well as substrate specificity. In addition, our results uncovered the presence of a functional nuclear export sequence in PRMT1v2. Finally, we find that the relative balance of PRMT1 isoforms is altered in breast cancer.
authors.affiliation: Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Goulet
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Gauvin
authors.forename: Sophie
authors.initials: S
authors.lastname: Boisvenue
authors.forename: Jocelyn
authors.initials: J
authors.lastname: Côté
mesh_terms: D017398:Alternative Splicing / Q000235:genetics*; D000595:Amino Acid Sequence; D001943:Breast Neoplasms / Q000378:metabolism; D045744:Cell Line, Tumor; D017124:Conserved Sequence; D005091:Exons / Q000235:genetics; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic; D015894:Genome, Human / Q000235:genetics; D006262:Health; D006801:Humans; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D007930:Leucine / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D011484:Protein-Arginine N-Methyltransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D013379:Substrate Specificity
chemical_list: D007527:Isoenzymes; D012097:Repressor Proteins; C099988:PRMT1 protein, human; D011484:Protein-Arginine N-Methyltransferases; D007930:Leucine