TABLE 1

Spontaneous can1 mutations in the pol3-Y708A strain and its rev3Δ derivative

pol3-Y708Apol3-Y708A rev3Δ
MutationNo.MR (×10−8)bNo.MR (×10−8)bRate of Polζ-dependent mutations (×10−8)c
Base substitutions
    GC → AT1118235.413
    AT → GC81371.611
    GC → TA1627204.722
    GC → CG55920<0.2392
    AT → CG7120<0.2312
    AT → TA2948368.440
    Total126a2108620190
Small indels
    −181340.9312
    −223.340.932.4
    −30<1.720.47<1.3
    −40<1.720.47<1.3
    −50<1.720.47<1.3
    +146.7143.33.4
    +20<1.710.23<1.5
    +411.70<0.23≤1.7
    Total1525296.818
Large rearrangements (≥8 nucleotides)
    Deletions between short direct repeats152592214.0
    Other deletions0<1.710.23<1.5
    Duplications0<1.710.23<1.5
Complex mutations type I (≤6 nucleotides)d244010.2340
Complex mutations type II (≥7 nucleotides)d0<1.740.93<0.8
Total180a30021450250
  • a Two can1 mutants of the pol3-Y708A strain carried double base substitutions. The mutations were separated by 93 and 476 nucleotides in these mutants. These were counted as four individual base substitutions.

  • b Rate for each type of mutation was calculated as follows: MRi = (Mi/MT) × MR, where Mi is the number of mutations of the particular type, MT is the total number of mutations, and MR is the rate of Canr mutation in the corresponding strain determined by fluctuation analysis, 3 × 10−6 for the pol3-Y708A and 5 × 10−7 for the pol3-Y708A rev3Δ strain (Northam et al. 2006).

  • c Rate of Polζ-dependent mutations was calculated by subtracting the rate for the pol3-Y708A rev3Δ strain from the rate for the pol3-Y708A strain.

  • d Complex mutations type I are defined as replacements of one to six adjacent nucleotides with a different sequence no more than six nucleotides long. Complex mutations type II are defined as replacements where the original sequence or the new sequence or both are longer than six nucleotides.