title: A novel methyltransferase required for the formation of the hypermodified nucleoside wybutosine in eucaryotic tRNA.
abstract: We demonstrate that the product of the yeast open reading frame YML005w is required for wybutosine (yW) formation in the phenylalanine-accepting tRNA of the yeast Saccharomyces cerevisiae. tRNA isolated from a deletion mutant of the YML005w gene accumulates 4-demethylwyosine (ImG-14), a precursor lacking three of the methyl groups of the yW hypermodified base. Since the amino acid sequence of the YML005w gene contains the signature motifs of the seven beta-strand methyltransferases, we now designate the gene TRM12 for tRNA methyltransferase. Using pulse-chase labeling of intact yeast cells with S-adenosyl-L-[methyl-(3)H]methionine, we show that the methylesterified form of yW is metabolically stable.
authors: Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA 90095-1560, USA.
authors: Hamid R
authors: HR
authors: Kalhor
authors: Mahmud
authors: M
authors: Penjwini
authors: Steven
authors: S
authors: Clarke
mesh_terms: D000595:Amino Acid Sequence; D015254:DNA Modification Methylases / Q000737:chemistry / Q000378:metabolism; D008745:Methylation; D008969:Molecular Sequence Data; D009705:Nucleosides / Q000096:biosynthesis* / Q000737:chemistry; D012343:RNA, Transfer / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D012359:tRNA Methyltransferases / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D009705:Nucleosides; C467591:wybutosine; D012343:RNA, Transfer; D015254:DNA Modification Methylases; D012359:tRNA Methyltransferases