Correlation between suppressed meiotic recombination and the lack of DNA strand-breaks in the rRNA genes of Saccharomyces cerevisiae.
We have examined whether the suppressed homologous meiotic recombination within the rDNA of S. cerevisiae is reflected by a lack of possibly recombination-initiating strand-breaks in this part of the genome. Our findings indicate that bulk DNA in the ds-break repair deficient mutant rad52/rad52 accumulates a limited number of both ss- and ds-breaks during meiosis as compared to a RAD+/rad52 heterozygote. The rDNA-containing chromosome is however protected against these breaks, and thus this may be an explanation for the suppression of recombination in the rDNA. The fact that ds-breaks seem to be involved gives indirect support to the ds-break-repair model for recombination.
D004261:DNA Replication; D004271:DNA, Fungal / Q000235:genetics*; D004275:DNA, Ribosomal / Q000235:genetics* / Q000302:isolation & purification; D005800:Genes, Fungal; D007700:Kinetics; D008540:Meiosis; D009693:Nucleic Acid Hybridization; D012335:RNA, Ribosomal / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics*; D013104:Spheroplasts / Q000502:physiology
D004271:DNA, Fungal; D004275:DNA, Ribosomal; D012335:RNA, Ribosomal