title: Influence of the nuclear gene tmp3 on the loss of mitochondrial genes in Saccharomyces cerevisiae.
abstract: The Saccharomyces cerevisiae tmp3 mutant is deficient in the mitochondrial enzyme complex that participates in the formation of one-carbon-group-tetrahydrofolate coenzymes, serine transhydroxymethylase, dihydrofolate reductase, and thymidylate synthetase, thus leading to multiple nutritional requirements of dTMP, adenine, histidine, and methionine. The tmp3 mutant quickly loses its mitochondrial genome even when grown on fully supplemented medium or on a high concentration of 5-formyl tetrahydrofolate, which replaces all the four requirements. A study of the loss of the mitochondrial genome by following several mitochondrial genetic markers showed that there was a preferential specific loss of a large region of the mitochondrial genome, covering mit ts983, Er, Cr, and mit ts982 up to OrI, and retention of the region of Pr and mit tscs1297. A kinetic study showed that there was a preferentially rapid loss of the region covering the mit+ alleles ts983 to tscs902 at the rate of 10% per generation.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002467:Cell Nucleus; D004271:DNA, Fungal / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D005819:Genetic Markers; D012696:Glycine Hydroxymethyltransferase / Q000235:genetics; D008928:Mitochondria / Q000378:metabolism; D009097:Multienzyme Complexes / Q000235:genetics*; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D013172:Spores, Fungal / Q000235:genetics; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics; D013940:Thymidylate Synthase / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D004271:DNA, Fungal; D004272:DNA, Mitochondrial; D005819:Genetic Markers; D009097:Multienzyme Complexes; D013762:Tetrahydrofolate Dehydrogenase; D013940:Thymidylate Synthase; D012696:Glycine Hydroxymethyltransferase