Identification of New Genes Required for Meiotic Recombination in Saccharomyces cerevisiae

• Published in: Genetics (Austin) Vol. 133; no. 1; pp. 51 - 66
• Main Authors: Ajimura, M, Leem, S. H, Ogawa, H
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Genetics Soc America 01.01.1993; Genetics Society of America
• Subjects: Alleles; Biological and medical sciences; Chromosomes, Fungal; Classical genetics, quantitative genetics, hybrids; Deoxyribonucleic acid; Diploidy; DNA; DNA, Fungal - biosynthesis; Fundamental and applied biological sciences. Psychology; Fungal Proteins - genetics; Genes, Fungal; Genetic Complementation Test; Genetics; Genetics of eukaryotes. Biological and molecular evolution; Haploidy; Investigations; Meiosis; Methyl Methanesulfonate - toxicity; Mutagenesis; Mutation; Recombination, Genetic; Saccharomyces cerevisiae; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae - physiology; Spores, Fungal; Thallophyta, bryophyta; Ultraviolet Rays; Vegetals; Recombination; Yeast; Meiosis; Spores; Fungi; DNA; Chromosome DNA; Ascomycetes; Complementation; Mutation; Molecular cloning; Saccharomyces cerevisiae; Thallophyta
• ISSN: 0016-6731; 1943-2631; 1943-2631
• DOI: 10.1093/genetics/133.1.51

Mutants defective in meiotic recombination were isolated from a disomic haploid strain of Saccharomyces cerevisiae by examining recombination within the leu2 and his4 heteroalleles located on chromosome III. The mutants were classified into two new complementation groups (MRE2 and MRE11) and eight previously identified groups, which include SPO11, HOP1, REC114, MRE4/MEK1 and genes in the RAD52 epistasis group. All of the mutants, in which the mutations in the new complementation groups are homozygous and diploid, can undergo premeiotic DNA synthesis and produce spores. The spores are, however, not viable. The mre2 and mre11 mutants produce viable spores in a spo13 background, in which meiosis I is bypassed, suggesting that these mutants are blocked at an early step in meiotic recombination. The mre2 mutant does not exhibit any unusual phenotype during mitosis and it is, thus, considered to have a mutation in a meiosis-specific gene. By contrast, the mre11 mutant is sensitive to damage to DNA by methyl methanesulfonate and exhibits a hyperrecombination phenotype in mitosis. Among six alleles of HOP1 that were isolated, an unusual pattern of intragenic complementation was observed.