title: Steady state analysis of mitochondrial RNA after growth of yeast Saccharomyces cerevisiae under catabolite repression and derepression.
abstract: The steady state levels of mitochondrial rRNAs, 5 tRNAs, the 9 S RNA, and the RNA products from the genes coding for subunits 6 and 9 of the ATP synthase, cytochrome b, and subunit 1 of cytochrome oxidase have been determined after growth of yeast under conditions of respiratory repression or derepression. The analysis indicates that the mitochondrial rRNAs are present in 2000 or 9000 copies/cell in repressed or derepressed yeast, respectively. The levels of the other RNAs also differed to a similar extent, with the exception of the level of the tRNAfMet which differs by only 1.7-fold. The levels of the individual protein coding RNAs varied from 480 copies/cell for the Oli-1 RNA to 100 copies/cell for the Oli-2 RNA under derepressive conditions and from 130 copies/cell to 33 copies/cell for the same RNAs in glucose repressive conditions. The levels of the tRNAs varied even more markedly, ranging from 4200 copies/cell for the tRNAPhe to 240 copies/cell for the tRNACys after growth in derepressive conditions and from 800 copies/cell for the tRNAfMet to 30 copies/cell for the tRNACys of glucose repressed yeast. These results indicate that glucose repression uniformly decreases the levels of the individual mitochondrial RNAs studied. This decrease is related to a lower synthesis of mitochondrial RNA in the glucose repressed cells as compared to derepressed cells.
mesh_terms: D005800:Genes, Fungal; D005947:Glucose / Q000494:pharmacology*; D007700:Kinetics; D010957:Plasmids; D012313:RNA / Q000235:genetics* / Q000378:metabolism; D000077278:RNA, Mitochondrial; D012343:RNA, Transfer / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D014158:Transcription, Genetic
chemical_list: D000077278:RNA, Mitochondrial; D012313:RNA; D012343:RNA, Transfer; D005947:Glucose