TABLE 3.
Increased commitment to meiotic intrachromosomal recombination in xrn1-D208A dmc1 double mutants compared to xrn1Δ dmc1 double mutants
| Relevant genotypea | Frequency of His+ Ade− popouts (10−4) atb:
|
Frequency of His+ Ade+ convertants (10−4) atb:
|
||||
|---|---|---|---|---|---|---|
| 0 h | 7 h | 24 h | 0 h | 7 h | 24 h | |
| wt | 5.4 | 103 (100%) | 550 (100%) | 11.4 | 105 (100%) | 350 (100%) |
| wt* | 5.8 | 84 (82%) | 459 (83%) | 8.7 | 118 (112%) | 367 (105%) |
| dmc1 | 19.4 | 502 (487%) | 588 (107%) | 12.6 | 122 (116%) | 307 (88%) |
| dmc1* | 13.4 | 552 (536%) | 741 (135%) | 10.3 | 157 (150%) | 374 (107%) |
| xrn1Δ | 3.1 | 46 (45%) | 211 (38%) | 9.8 | 133 (126%) | 237 (68%) |
| xrn1-D208A | 3.9 | 158 (153%) | 298 (54%) | 15.6 | 121 (115%) | 224 (64%) |
| dmc1 xrn1Δ | 3.5 | 29 (28%) | 34 (6%) | 4.2 | 37 (35%) | 66 (19%) |
| dmc1 xrn1-D208A | 1.7 | 130 (126%) | 164 (30%) | 2.9 | 111 (106%) | 121 (35%) |
All strains carry his4-B::ADE2::his4-X on one homolog of chromosome III and his4-B on the other. They are isogenic derivatives of SK-1 strains: WDHY1450 (wt), WDHY1451 (wt*), WDHY1452 (dmc1), WDHY1543 (dmc1*), WDHY1454 (xrn1Δ), WDHY1455 (xrn1-D208A), WDHY1456 (dmc1 xrn1Δ), and WDHY1457 (dmc1 xrn1-D208A).
Four independent diploids for each genotype were sporulated, and the means are given. The differences between the values discussed in the text are statistically significant, since their standard deviations do not overlap. Commitment to meiotic recombination levels was measured as described in the text, and each meiotic value represents the meiotic frequency minus the mitotic (0-h) frequency (86). Numbers in parentheses indicate the frequency of recombination in the mutant as a percent of the wild-type frequency.