TABLE 2.
Conversion tract parametersa
| Parameter | Mean value (95% CI) in the following background:
|
||
|---|---|---|---|
| WTb | msh2 msh3 mutantc | pms1 mutantd | |
| Orientation 1 | |||
| Minimal length (bp) | 252 (211, 293) | 364 (321, 407) | 304 (232, 376) |
| Maximal length (bp) | 298 (260, 336) | 406 (365, 447) | 350 (283, 417) |
| Average length (bp) | 275 (235, 315) | 385 (343, 428) | 327 (257, 397) |
| No. of mismatches converted | 14.4 (12, 16.8) | 21.2 (18.5, 23.9) | 17.6 (13.3, 21.9) |
| Orientation 2 | |||
| Minimal length (bp) | 212 (153, 271) | 319 (270, 368) | |
| Maximal length (bp) | 248 (186, 310) | 359 (308, 410) | |
| Average length (bp) | 230 (170, 290) | 339 (289, 389) | |
| No. of mismatches converted | 14.2 (10.3, 18.1) | 21.5 (18.4, 24.6) | |
The minimal, maximal, and average conversion tract lengths, as well as the number of mismatches converted, were determined according to the sister chromatid conversion model. The numbering system for nucleotide positions is that shown in Fig. 2A, where position 1 is the 5′-most nucleotide. The minimal extent of a given conversion tract was calculated as the sum of conversion tracts to the left and right of the invertible segment (see Fig. 6). For the substrates in orientation 1, each of the 5′ ends was distal, and each of the 3′ ends was proximal, to the invertible segment. The left and right conversion tract lengths were calculated individually by subtracting the position of the most distal mismatch converted (i.e., the most distal with respect to the invertible segment) from 350 bp. For the substrates in orientation 2, the 5′ and 3′ ends of the substrates were proximal and distal, respectively, to the invertible segment. The left and right conversion tract lengths were calculated individually by subtracting 6 bp from the position of the most distal mismatch converted. To determine the maximal length of a given conversion tract obtained by using either orientation 1 or orientation 2 substrates, the lengths of the identity intervals that flanked the minimal tract on either side were added to the minimal tract length. The average length of a given conversion tract was calculated as the mean of the minimal and maximal conversion tract lengths. The number of mismatches converted was counted manually for each recombinant according to the sister chromatid conversion model.
WT, wild type. The number of conversion tracts included in the analysis was 56 for orientation 1 substrates and 24 for orientation 2 substrates.
The number of conversion tracts included in the analysis was 52 for orientation 1 substrates and 25 for orientation 2 substrates.
Twenty-seven conversion tracts were included in the analysis.