Fig. 2.

Extension of a ³²P-labeled 24-mer primer opposite G and AP site at position 25 by human Y-family and B-family DNA polymerases. Primer (24-mer) was annealed with each of the two different 36-mer templates (Table 1) containing an unmodified G or AP site (tetrahydrofuran) placed at the 25th position from the 3′-end (see Fig. 1). Reactions were done for 10 min with increasing concentrations of (a) Y-family DNA polymerases: pols η (0 − 5 nM), ι (0 − 10 nM), κ (0 − 50 nM) or REV1 (0 − 50 nM) and (b) B-family DNA polymerases: pols α (0 − 16 nM) or δ (0 − 20 nM)/PCNA (300 nM), with a constant concentration of DNA substrate (100 nM primer/template) as indicated. ³²P-labeled 24-mer primer was extended in the presence of all four dNTPs. The reaction products were analyzed by denaturing gel electrophoresis with subsequent phosphoimaging analysis.