Recombination frequencies at the CUP1, rDNA, and SUP4-o loci
| CUP1a: 5-FOAR/total ×106 | rDNAb: 5-FOAR/total ×105 | SUP4-oc: 5-FOAR Ade− CanR/total ×107 | |
|---|---|---|---|
| WT | 3.7 (± 0.96)d | 16 (± 3.8) | 2.1 (± 1.1) |
| pif1e | 88 (± 12) | 29 (± 6.6) | 16 (± 7.1) |
| rrm3 | 100 (± 27) | 140 (± 66) | 4.3 (± 3.2) |
| sgs1 | 78 (± 6.1) | 130 (± 28) | 25 (± 6.1) |
| top3 | 188 (± 43) | 220 (± 71) | 180 (± 47) |
| sgs1 top3 | 84 (± 26) | 40 (± 24) | 46 (± 6.4) |
↵a The CUP1 locus consists of six to seven 2.0-kb direct repeats in the assay strain (W1588-4C background) as determined by gel blot analysis and phosphorimager quantitation (data not shown).
↵b The rDNA locus contains 150–200 9.2-kb direct repeats in tandem as well as a replication fork barrier in each repeat.
↵c The SUP4-o locus contains five ∼330-bp δ repeats in both direct and inverse orientations as well as replication pause sites (Rothstein et al. 1987).
↵d See materials and methods for details of how each assay was performed. Each value represents the deletion frequency between direct repeats at the indicated locus and is the average of a minimum of five experiments in which independent segregants were used. Standard deviations are given in parentheses.
↵e Null mutant strains were used except in the case of the SUP4-o assay in which case the pif1-m2 strain was used for technical reasons (see materials and methods). Strains used in this analysis were constructed by crossing the appropriate mutation into the appropriate assay strain: W3831-1B (CUP1 assay), W3480-4C (rDNA assay), or W1868-8B (SUP4-o assay). The sgs1 and top3 deletions were derived from a W1958 segregant. The pif1 deletion was derived from strain J1129. The pif1-m2 mutation was derived from strain W3972-7C. The rrm3 deletion was derived from strain J1132.