TABLE 2.
Requirement for M26, Spc1, Mts1, and Mts2 in hot spot meiotic recombination
| Relevant genotypea
|
Ade+ recombination frequency (104)b
|
Hot spot ratioc | |||
|---|---|---|---|---|---|
| mts1/mts1 | mts2/mts2 | spc1/spc1 | M375 × M210 | M26 × M210 | |
| +/+ | +/+ | +/+ | 6.8 ± 1.5 | 78 ± 9.0 | 11 |
| −/− | +/+ | +/+ | 6.5 ± 1.1 | 5.0 ± 0.6 | 0.8 |
| +/+ | −/− | +/+ | 4.4 ± 0.9 | 4.8 ± 0.9 | 1.1 |
| +/+ | +/+ | −/− | 5.2 ± 1.4 | 3.3 ± 1.0 | 0.6 |
| −/− | −/− | +/+ | 9.6 ± 4.0 | 9.6 ± 4.0 | 1.0 |
| −/− | +/+ | −/− | 5.5 ± 2.6 | 6.7 ± 1.2 | 1.2 |
| +/+ | −/− | −/− | 4.9 ± 3.3 | 4.3 ± 2.1 | 0.9 |
Plus signs indicate mts1+, mts2+, or spc1+; minus signs indicate deleted mts1 (mts1-D15::his3+ or mts1-D15::ura4+) (Table 1) (20), deleted mts2 (mts2-D1::his3+) (20), or deleted spc1 (spc1::ura4+) (38). All strains also have the genotype leu1-32 ura4-D18 his3-D1 (Table 1).
See Fig. 1 for positions of ade6 alleles. Standard genetic crosses (12, 14, 37) were conducted, and spores were plated on supplemented NBA minimal medium containing adenine (100 μg/ml) to determine the total viable spore titer (T) and on NBA medium lacking adenine to determine the ade6+ recombinant titer (R). At least 100 colonies of each type were counted for each cross. The recombination frequency for each experiment is R/T. Data are means ± standard deviations of recombination frequencies from four experiments.
Ratio of recombination frequency from the M26 × M210 (hot spot) cross to that from the M375 × M210 (basal recombination) cross.