The transmission disadvantage of yeast mitochondrial intergenic mutants is eliminated in the mgt1 (cce1) background.
A trans-acting element, MGT1 (also called CCE1), has previously been shown to be required in Saccharomyces cerevisiae for the preferential transmission of petite mitochondrial DNA (mtDNA) molecules over wild-type mtDNA molecules. In the present study a possible role of this nuclear gene in the transmission of mtDNA from various respiration-competent mutants was studied. Several of these mutants, lacking one or the other of two biologically active mitochondrial intergenic sequences, were employed in genetic crosses. When these deletion mutants were crossed to the parental wild-type strain in the MGT1/CCE1 background, the progeny contained predominantly wild-type mtDNA molecules. When crosses were performed in the mgt1/cce1 background, the parental molecules interacted in zygotes and underwent homologous recombination but wild-type and intergenic-deletion alleles were transmitted with equal frequencies.
Piskur
J
J
Department of Genetics, Institute of Molecular Biology, University of Copenhagen, Denmark. jp@im.dtu.dk
D003433:Crosses, Genetic; D004271:DNA, Fungal / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D004706:Endodeoxyribonucleases / Q000235:genetics / Q000502:physiology*; D045565:Holliday Junction Resolvases; D008928:Mitochondria; D009154:Mutation; D011995:Recombination, Genetic / Q000235:genetics*; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins
D004271:DNA, Fungal; D004272:DNA, Mitochondrial; D029701:Saccharomyces cerevisiae Proteins; D004706:Endodeoxyribonucleases; C473486:CCE1 protein, S cerevisiae; D045565:Holliday Junction Resolvases