Restoration of T-dT repair at position 686 by removing a flanking triplet repeat.
Mismatch repair correction factors for errors created by M644G Pol ε in ATT3 (dark blue columns) and ATT0 (light blue columns) URA3 sequences. The T-dT mismatch at position 686 and the surrounding sequence context are shown below the chart: nascent strand above; template strand below. Triangles indicate the direction of synthesis. The three silent mutations made to convert ATT3 into ATT0 URA3 are underlined. Note that the polymerase active site encounters the triplet repeat in the ATT3 template strand after making the T-dT mismatch at position 686. ≤ Upper bound, estimated by increasing msh2Δ observation count from 0 to 1 for purposes of correction factor calculations.