Table 1. Effect of Cmr1 on mutation rates and chromosome loss.
| a. Mutation rates | |||
|---|---|---|---|
| Genotype | Strain |
Mutation rate (fold change*) |
|
| CanR (× 10−7) | Lys+ (× 10−7) | ||
| Wild type | IG106-4D | 3.8 | 4.5 |
| cmr1Δ | IG106-1C | 4.7 (1.2) | 16 (4)† |
| mlh1Δ | IG106-5A | 63 (17)† | 77420 (17204)† |
| cmr1Δ mlh1Δ | IG106-1D | 91 (24)† | 23790 (5278)†,‡ |
| msh2Δ | IG137- 66D | 56 (15)† | 30950 (6878)† |
| cmr1Δ msh2Δ | IG137-28C | 338 (89)†,‡ | 43530 (9673)† |
| mrc1Δ | IG172-7C | 16 (4)† | 6.2 (1.4) |
| cmr1Δ mrc1Δ | IG172-4B | 21 (6)† | 6.9 (1.5) |
|
b. Replication stress-induced mutation frequencies | |||
|---|---|---|---|
| Genotype | Strain |
Mutation frequency (fold change*) |
|
| CanR (× 10−7) | Lys+ (× 10−7) | ||
| Wild type | IG106-4D | 53 | 40 |
| cmr1Δ | IG106-1C | 34 (0.6) | 99 (2.5)† |
|
c. Rates of chromosome loss (BiM assay)70 | |||
|---|---|---|---|
| Genotype | Strains | Chromosome loss (× 10−2) (fold change*) | s.d. (× 10−2) |
| Wild type | ML8-9A × W4700-10C | 3.3 | 0.5 |
| cmr1Δ | IG79-6D × DP1 | 6.6 (2)† | 1.1 |
| rad52Δ | SMG259-3C × SMG259-11B | 7.5 (2.3)† | 1.6 |
| cmr1Δ rad52Δ | IG162-2D × IG184-11C | 14.5 (4.5)†,‡ | 3.3 |
| Wild type | ML8-9A × W4700-10C | 0.4 | 0.09 |
| cmr1Δ | IG79-6D × DP1 | 0.8 (2.1) | 0.7 |
| mrc1Δ | IG156-7D × IG179-3B | 3.1 (7.8)† | 0.8 |
| cmr1Δ mrc1Δ | IG156-9B × IG156-9C | 1.9 (4.8)† | 0.5 |
BiM, bimaters assay; MMS, methyl methanesulfonate.
(a) Spontaneous mutation rates. Forward (CanR) and frameshift (LYS214A) mutation rates were determined for IG106-4D (wt), IG106-1C (cmr1Δ), IG106-5A (mlh1Δ), IG106-1D (cmr1Δ mlh1Δ), IG137-66D (msh2Δ), IG137-28C (msh2Δ cmr1Δ), IG172-7C (mrc1Δ) and IG172-4B (mrc1Δ cmr1Δ). (b) Induced mutation frequencies. Fold change compared with wild type is indicated in parentheses. Replication stress-induced mutation frequencies were determined after growth in 0.03% MMS for 30 min. (c) Rates of chromosome loss (BiM assay). Diploid strains homozygous for the indicated gene deletions were grown on rich medium and subsequently tested for the ability to mate with a MATa tester strain (R113). Frequency of mating, derived from loss of the endogenous MATa locus, is used as a measure of chromosomal instability. The two sets of BiM assays were performed with different batches of media; s.d. of the rate is reported.
*Relative to wild type.
†Significant (P<0.05) compared with wild type.
‡Significant (P<0.05) difference between single and double mutant.