title: tRNAs undermethylation in a met-regulatory mutant of Saccharomyces cerevisiae.
abstract: A study of in vivo and in vitro methylation of tRNAs in regulatory mutants affected in methionine-mediated repression (eth2, eth3, eth10) has led to the following results: 1) The eth2-2 carrying strain presents a great undermethylation of its tRNAs of the same order of magnitude as observed during methionine starvation of methionine auxotrophs. 2) This undermethylation leads to a shift of the tRNAIII met peak on a BD cellulose column, while tRNAIII met peak is unchanged. 3) The study of a double mutant strain carrying eth2 and met2 mutations has shown that this undermethylation is a consequence of the high internal pool of methionine. 4) Undermethylation unequally affects the different bases and the different tRNA species.
mesh_terms: D002250:Carbon Radioisotopes; D002848:Chromatography, DEAE-Cellulose; D002855:Chromatography, Thin Layer; D004591:Electrophoresis, Polyacrylamide Gel; D004794:Enzyme Repression; D006238:Haploidy; D008715:Methionine / Q000096:biosynthesis*; D008745:Methylation; D009154:Mutation; D009711:Nucleotides / Q000032:analysis; D012343:RNA, Transfer / Q000378:metabolism*; D012436:S-Adenosylmethionine / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D014316:Tritium; D012359:tRNA Methyltransferases / Q000378:metabolism
chemical_list: D002250:Carbon Radioisotopes; D009711:Nucleotides; D014316:Tritium; D012436:S-Adenosylmethionine; D012343:RNA, Transfer; D008715:Methionine; D012359:tRNA Methyltransferases