Fig. 3.

DME and ROS1 excise 5-meC and thymine but not uracil. (A) Double-stranded oligonucleotide substrates containing 5-mec (M), T·G, or U·G mismatches in CpG (CXGG) and non-CpG (XCGG, XAG, and AXT) sequence contexts were incubated with purified DME (Upper) or ROS1 (Lower) as described in Materials and Methods. Reaction products were separated in a 12% denaturing polyacrylamide gel and visualized by autoradiography. (B) Double-stranded oligonucleotide substrates containing 5-meC (M), T·G, or U·G mismatches in a CpG sequence context were incubated for 24 h with purified WT DME or mutant DME D1562A (Upper) or WT ROS1 or mutant ROS1 D971A (Lower). Reaction products were separated in a 12% denaturing polyacrylamide gel and visualized by autoradiography.