Figure 2.

Extension of ³²P-labeled primers opposite G, O⁶-MeG, N²-EtG, 8-oxoG, and an abasic site by human wild-type pol ι (1–445) and variants in the presence of Mg²⁺. The primer (24-mer) was annealed with each of the five different 36-mer templates containing an unmodified G, O⁶-MeG, N²-EtG, 8-oxoG, or abasic site placed at the 25th position from the 3′-end. Reactions were done in the presence of 5 mM MgCl₂ for 15 min with DNA substrate (100 nM primer/template), all four dNTPs (50 μM each), and increasing concentrations of pol ι (0–50 nM) as indicated. The extension products were separated by denaturing gel electrophoresis and imaged using a phosphorimager.