Figure 2.

Incorporation of pyrimidine nucleotides opposite tT and base-adducted tT in a DNA template by hPol η and comparison with the corresponding 2′-deoxynucleotides as analyzed by 15% TBE-urea PAGE. The gel images depict incorporation of (A) dCTP and (B) dTTP opposite tT, top, O⁴-Me tT, center, and O⁴-Et tT, bottom (right panels), as well as opposite the corresponding dTs (left panels). In each assay, 10 nM hPol η was incubated with 150 nM DNA template:primer at 37 °C, followed by addition of 50 μM dCTP or dTTP. At the indicated time points, aliquots were removed and mixed with quencher. In each panel, the first lane is the 5′-FAM-labeled primer band before annealing with the template. Each replication experiment is done in triplicates as independent sets of experiments.