title: A nuclear mutation affecting mitochondrial transcription in Saccharomyces cerevisiae.
abstract: Mitochondrial transcription was studied in a nuclear temperature-sensitive pet mutant of Saccharomyces cerevisiae. The mitochondrial RNA levels in vivo and the in vitro transcriptional activities of isolated mitochondria were analysed. In comparison to the wild-type an overall reduction of mitochondrial gene expression together with a changed expression pattern was observed for the mutant, indicating a defect in mitochondrial RNA synthesis. These findings were supported by studies with a purified DNA-protein complex from yeast mitochondria. This complex was able to synthesize ribosomal and messenger RNAs in an in vitro system. Proteins from wild-type and mutant transcription complexes were tested for their DNA-binding abilities; one of the proteins identified in the wild type had either lost this ability or was absent in the mutant.
mesh_terms: D002467:Cell Nucleus; D004591:Electrophoresis, Polyacrylamide Gel; D008928:Mitochondria / Q000378:metabolism*; D009154:Mutation; D009693:Nucleic Acid Hybridization; D012331:RNA, Fungal / Q000032:analysis; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D012331:RNA, Fungal