title: Fine-structure analysis of intercellular and intracellular mitochondrial diversity in Saccharomyces cerevisiae.
abstract: Crosses were made between haploid wild-type and suppressive petite strains of bakers' yeast to obtain zygotes for analysis of mitochondrial heterogeneity. Wild-type x petite zygotes contained about 40% noncristate mitochondria when immediate mating mixtures were examined. The frequency of defective mitochondria had decreased to an average of 9.2% in 1-week-old zygote isolate cultures, and to 4.4% in slant cultures 1.5 years after initial zygote isolation. The latter value was not significantly different from values obtained with wild x wild zygotes of either age. The noncristate mitochondria were of two types: one lacking inner membrane invaginations or elaborations and the other containing concentrically arranged loops of inner membrane. The significance of these two types of respiration-deficient mitochondria is unknown. The gradual decrease in frequency of noncristate mitochondria, perhaps due to selection pressures in mixed chondriomes, was discussed as a further indication of the semiautonomous nature of the yeast organelle.
mesh_terms: D003227:Conjugation, Genetic; D003433:Crosses, Genetic; D003593:Cytoplasm; D003576:Electron Transport Complex IV / Q000378:metabolism; D004721:Endoplasmic Reticulum; D006651:Histocytochemistry; D006824:Hybridization, Genetic; D008566:Membranes; D008854:Microscopy, Electron; D008928:Mitochondria / Q000378:metabolism; D010641:Phenotype; D012440:Saccharomyces / Q000166:cytology* / Q000201:enzymology
chemical_list: D003576:Electron Transport Complex IV