Table 3.
Frequency of large deletions between direct repeats
| WT Pol δ | Exo− Pol δ | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Repeat + inverted repeat | Repeat only | Repeat + inverted repeat | Repeat only | ||||||
| Number | Frequencya | Number | Frequency | Number | Frequency | Number | Frequency | ||
| Pol δ only | 80 | 240 | 1 | 3.0 | 50 | 250 | 5 | 25 | |
| + RPA | 3 | 6.8 | 1 | 2.3 | 6 | 23 | 0 | ≤3.8 | |
| + PCNA + RFC | 4 | 9.1 | 2 | 4.6 | 4 | 16 | 5 | 20 | |
| + RPA + PCNA + RFC | 0 | ≤2.7 | 0 | ≤2.7 | 0 | ≤4.3 | 0 | ≤4.3 | |
These large deletions involve loss of multiple nucleotides between direct repeats of two or more bases. Those listed as involving an inverted repeat could theoretically be stabilized by a ‘stem’ of at least two correct base pairs, in rare cases allowing for one mismatch, e.g. a T–G mismatch.
aWhile error rates for single base events in Table 2 are expressed as ‘errors per nucleotide incorporated’, the values for deletion of multiple bases are expressed here simply as mutant frequencies (× 10−5).