Figure 7.

Influence of gapped DNA on the bypass of a major groove DNA lesion with mutants of pol β. Replication on an unadducted template with K234A, Y271A, N279A, and R283K, (panels A, D, G, and J, respectively). The efficiencies of bypass and measurement of incorporation beyond the control dA templating base were calculated at different dTTP concentrations in the absence or presence of a downstream strand (square and triangle symbols, respectively). Bypass efficiencies were calculated as outlined in Experimental Procedures. All reactions included 10 fmol of pol β and were carried out for 5 min. Bypass with a C₁₀S BPDE-dA adducted template with K234A, Y271A, N279A, and R283K, (panels B, E, H, and K, respectively). Bypass with a C₁₀R BPDE-dA adducted template with K234A, Y271A, N279A, and R283K, (panels C, F, I, and L, respectively).