TABLE 5

Meiotic segregation patterns of the arg4-17 marker

Sporulation temperatureStrainRelevant genotypeNo. tetradsAb tetrads (%)PMS tetradsb (%)PMS/Ab events (%)
30°PD83WT3359.600
No. 5msh2Δ798.9557
JSY175pol30-52741.41.4100c
18°MW103/JSY338aWT7427.50.11.7
JSY240/JSY343amsh2Δ502161167
JSY346pol30-2013368.61.516d
JSY354pol30-201 msh2Δ184113.835e
JSY230mlh1Δ192136.850
SJR2577 × SJR2578mlh1-QLF226201050f
SJR2705 × SJR2706bWT165131.29.1
SJR2705 × SJR2707bmsh6-FFAA,Δ51-251305141.611g
  • The columns of % events are as follows: % Ab tetrads, percentage of total tetrads with aberrant (non-4:4) segregation; % PMS tetrads, percentage of total tetrads with one or more PMS events, excluding tetrads with one gene conversion event and one PMS event (7:1, 1:7); % PMS/Ab events, percentage of aberrant events that are PMS events, calculated as described by Stone and Petes (2006). Two-tailed Fisher's exact tests were used to determine P-values and P-values were considered significant when <0.05. WT, wild type.

  • a Data from Stone and Petes (2006). MW103/JSY338 and [JSY240/JSY343, JSY230] are isogenic to PD83 and No. 5, respectively, except for mutations at the HIS4 locus, which have no significant effect on segregation of the arg4-17 marker. Data from MW103/JSY338, JSY240/JSY343, and JSY230 are shown because spore colonies from these strains were examined microscopically for small sectors on medium lacking arginine, while spore colonies from 18° sporulations of PD83 and No. 5 were not.

  • b Alleles were encoded by the following plasmids: MSH6 by pRDK3572 and msh6-FFAA,Δ51-251 by pRDK4758 (Shell et al. 2007). To ensure that the plasmid was present during meiosis, only those tetrads that had at least one Leu+ spore were scored.

  • c Significant increase from PD83 (P = 0.03) but no significant difference from No. 5 (P = 1) in the number of PMS vs. the number of non-PMS aberrant events.

  • d Significant increase from MW103/JSY338 (P = 0.02) and significant decrease from JSY240/JSY343 (P < 0.001) in the number of PMS vs. the number of non-PMS aberrant events.

  • e Significant increase from MW103/JSY338 (P < 0.001), significant decrease from JSY240/JSY343 (P = 0.01), and no significant change from JSY346 (P = 0.18) in the number of PMS vs. the number of non-PMS aberrant events.

  • f Significant increase from MW103/JSY338 (P < 0.001) and no significant change from JSY230 (P = 1) in the number of PMS vs. the number of non-PMS aberrant events.

  • g No significant difference from SJR2705 × SJR2706 (P = 1).