title: Assembly of the mitochondrial membrane system: nuclear suppression of a cytochrome b mutation in yeast mitochondrial DNA.
abstract: In a previous study, a mitochondrial mutant expressing a specific enzymatic deficiency in co-enzyme QH2-cytochrome c reductase was described (TZAGO-LOFF, FOURY and AKAI 1976). Analysis of the mitochondrially translated proteins revealed the absence in the mutant of the mitochondrial product corresponding to cytochrome b and the presence of a new low molecular weight product. The premature chain-termination mutant was used to obtain suppressor mutants with wild-type properties. One such revertant strain was analyzed genetically and biochemically. The revertant was determined to have a second mutation in a nuclear gene that is capable of partially suppressing the original mitochondrial cytochrome b mutation. Genetic data indicate that the nuclear mutation is recessive and is probably in a gene coding for a protein involved in the mitochondrial translation machinery.
mesh_terms: D003580:Cytochromes / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics*; D009154:Mutation; D014176:Protein Biosynthesis; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D013489:Suppression, Genetic
chemical_list: D003580:Cytochromes; D004272:DNA, Mitochondrial