Figure 1.

Effect of the AP endonuclease HAP1 upon the 8-oxoG DNA glycosylase activity of hOGG1. (A) hOGG1 glycosylase activity on a 34mer [8-oxoG:C] duplex ³²P-labelled at the 5′-end on the lesion-containing strand. A limiting amount (2.5 fmol) of hOGG1 was incubated under standard assay conditions with the double-stranded oligonucleotide substrate (50 fmol) and increasing amounts of HAP1. Reactions were stopped by treatment with 10 mM EDTA and 0.2 N NaOH and heating for 30 min at 90°C as described in Materials and Methods. The products of the reactions were separated by denaturing 20% PAGE. (B) Quantification of the results from the gel displayed in (A).