Figure 2.

DNMT3A^WT tetramer interface mutants show highly variable response to p53^WT inhibition. Crystal structure of a DNMT3A^WT-DNMT3L complex (adapted from PDB code 5YX2) denoting critical residues for DNMT3A^WT oligomerization (A) (36, 50). Although the extent of p53^WT inhibition varies across DNMT3A^WT mutants harboring a single alanine substitution within the tetramer interface, the DNMT3A^R736A was unresponsive to p53^WT inhibition (B and C). All reactions consisted of 150 nm DNMT3A^WT and were initiated by the addition of 5 μm bp poly(dI-dC). For co-incubations, DNMT3A^WT and p53^WT (1:1) were preincubated for 1 h at 37 °C prior to starting the reaction by the addition of substrate DNA. Fold-inhibition was calculated by product formed by DNMT3A (WT and mutants) divided by product formed by DNMT3A (WT and mutants) without p53^WT. All reactions were performed in duplicates. In B, a Student's unpaired t test was used to compare values within each set of reactions; **, p < 0.01; ns, p > 0.05. For C, a one-way analysis of variance was used to compare the values of each mutant to WT (****, p < 0.001) and across all samples (orange ****, p < 0.001). Data reflect the mean ± S.D. of 3 experiments.