Figure 3: Spore viability and meiotic recombination in exo1∆ and rqh1∆ single and double mutants.

(a) Schematic showing the meiotic recombination assay at ade6 (yellow) and its common outcomes. The positions of ade6 and the artificially introduced markers ura4⁺-aim2 (green) and his3⁺-aim (blue) on chromosome 3 are indicated (in bp). The point mutation in ade6-3083 is shown in red, and ade6-L469 labelled in light blue. The ade6-3083 allele is a strong hotspot for meiotic DSB formation, whereas ade6-L469 is a non-hotspot, and therefore the former acts as the recipient of genetic information in crosses. (b) Viability of progeny from wild type and mutant crosses; ALP649xALP688 (WT, n = 10), MCW3748xMCW3749 (exo1∆, n = 10), MCW3387xMCW3388 (rqh1∆, n = 10), MCW4479xMCW4480 (exo1∆ rqh1∆, n = 10). (c) Frequency of Ade⁺ gene conversions in wild type and mutant crosses; MCW3202xMCW3200 (WT, n = 21), MCW4268xMCW4269 (exo1∆, n = 11), MCW3385xMCW3384 (rqh1∆, n = 10), MCW4270xMCW4271 (exo1∆ rqh1∆, n = 13). (d) Frequency of crossovers between ura4⁺-aim2 and his3⁺-aim in wild type and mutant meioses; crosses as in (c). (e) Frequency of gene conversions associated with a crossover in wild type and mutant crosses; crosses as in (c). Data are represented as mean ± standard deviation and n indicates the number of independent crosses.