FIGURE 6.

Calorimetric titrations of ING4-PHD with H3₁₀K4meX peptides. Shown are examples of the direct titrations of the H3₁₀K4me3, H3₁₀K4me2, and H3₁₀K4me1 peptides together with the displacement experiment for H3₁₀K4me0 using H3₁₀K4me1 as competing ligand. In all cases, the upper panels represent the heat effect associated with the peptide injections, and the lower panels represent the ligand concentration dependence of the heat released upon binding, after normalization and correction for the heats of dilution. The symbols correspond to the experimental data, and the continuous line corresponds to the best fit to a model of one set of identical binding sites (as described in the supplemental materials) for H3₁₀K4me3, -me2, and -me1 and to a complete displacement model for H3₁₀K4me0.