Publications

• S-adenosylmethionine-dependent methylation in Saccharomyces cerevisiae. Identification of a novel protein arginine methyltransferase.

  Niewmierzycka A., Clarke S.

  We used sequence motifs conserved in S-adenosylmethionine-dependent methyltransferases to identify 26 putative methyltransferases from the complete genome of the yeast Saccharomyces cerevisiae. Seven sequences with the best matches to the methyltransferase consensus motifs were selected for furthe ... >> More

  We used sequence motifs conserved in S-adenosylmethionine-dependent methyltransferases to identify 26 putative methyltransferases from the complete genome of the yeast Saccharomyces cerevisiae. Seven sequences with the best matches to the methyltransferase consensus motifs were selected for further study. We prepared yeast disruption mutants of each of the genes encoding these sequences, and we found that disruption of the YJL125c gene is lethal, whereas disruptions of YCR047c and YDR140w lead to slow growth phenotypes. Normal growth was observed when the YDL201w, YDR465c, YHR209w, and YOR240w genes were disrupted. Initial analysis of protein methylation patterns of all mutants by amino acid analysis revealed that the YDR465c mutant has a defect in the methylation of the delta-nitrogen atom of arginine residues. We propose that YDR465c codes for the methyltransferase responsible for this recently characterized type of protein methylation, and we designate the enzyme as Rmt2 (protein arginine methyltransferase). In addition, we show that the methylation of susceptible residues in Rmt2 substrates is likely to take place on nascent polypeptide chains and that these substrates exist in the cell as fully methylated species. Interestingly, Rmt2 has 27% sequence identity over 138 amino acids to the mammalian guanidinoacetate N-methyltransferase, an enzyme responsible for methylating the delta-nitrogen of the small molecule guanidinoacetate. << Less

  J. Biol. Chem. 274:814-824(1999) [PubMed] [EuropePMC]

• The arginine methyltransferase Rmt2 is enriched in the nucleus and co-purifies with the nuclear porins Nup49, Nup57 and Nup100.

  Olsson I., Berrez J.M., Leipus A., Ostlund C., Mutvei A.

  Arginine methylation is a post-translational modification of proteins implicated in RNA processing, protein compartmentalization, signal transduction, transcriptional regulation and DNA repair. In a screen for proteins associated with the nuclear envelope in the yeast Saccharomyces cerevisiae, we ... >> More

  Arginine methylation is a post-translational modification of proteins implicated in RNA processing, protein compartmentalization, signal transduction, transcriptional regulation and DNA repair. In a screen for proteins associated with the nuclear envelope in the yeast Saccharomyces cerevisiae, we have identified the arginine methyltransferase Rmt2, previously shown to methylate the ribosomal protein L12. By indirect immunofluorescence and subcellular fractionations we demonstrate here that Rmt2 has nuclear and cytoplasmic localizations. Biochemical analysis of a fraction enriched in nuclei reveals that nuclear Rmt2 is resistant to extractions with salt and detergent, indicating an association with structural components. This was supported by affinity purification experiments with TAP-tagged Rmt2. Rmt2 was found to co-purify with the nucleoporins Nup49, Nup57 and Nup100, revealing a novel link between arginine methyltransferases and the nuclear pore complex. In addition, a genome-wide transcription study of the rmt2Delta mutant shows significant downregulation of the transcription of MYO1, encoding the Type II myosin heavy chain required for cytokinesis and cell separation. << Less

  Exp. Cell Res. 313:1778-1789(2007) [PubMed] [EuropePMC]

• Yeast ribosomal protein L12 is a substrate of protein-arginine methyltransferase 2.

  Chern M.-K., Chang K.-N., Liu L.-F., Tam T.-C.S., Liu Y.-C., Liang Y.-L., Tam M.F.

  Type III protein-arginine methyltransferase from the yeast Saccharomyces cerevisiae (RMT2) was expressed in Escherichia coli and purified to apparent homogeneity. The cytosolic, ribosomal, and ribosome salt wash fractions from yeast cells lacking RMT2 were used as substrates for the recombinant RM ... >> More

  Type III protein-arginine methyltransferase from the yeast Saccharomyces cerevisiae (RMT2) was expressed in Escherichia coli and purified to apparent homogeneity. The cytosolic, ribosomal, and ribosome salt wash fractions from yeast cells lacking RMT2 were used as substrates for the recombinant RMT2. Using S-adenosyl-l-methionine as co-substrate, RMT2 methylated a protein in the ribosome salt wash fraction. The same protein in the ribosomal fraction was also methylated by RMT2 after pretreating the sample with endonuclease. Amino acid analysis affirmed that the labeling products were delta-N-monomethylarginines. The methylated protein from the ribosomal or the ribosome salt wash fraction was isolated by two-dimensional gel electrophoresis and identified as ribosomal protein L12 by mass spectrometry. Using synthetic peptides, recombinant L12, and its mutant as substrates, we pinpointed Arg(67) on ribosomal protein L12 as the methyl acceptor. L12 was isolated from wild type yeast cells that have been grown in the presence of S-adenosyl-l-[methyl-(3)H]methionine and subjected to amino acid analysis. The results indicate that L12 contains delta-N-monomethylarginines. << Less

  J. Biol. Chem. 277:15345-15353(2002) [PubMed] [EuropePMC]