FIGURE 3.
Interaction of Vps75-Rtt109 with (H3-H4)2 probed using NMR spectroscopy-based hydrogen/deuterium exchange measurements. A, per amino acid ratio of histone H3 amide proton occupancies after exchange in D2O for 10 min in the absence and presence of Vps75 (black squares) or Vps75-Rtt109 (red dots). Analysis was possible for 42 histone H3 amino acids whose signals are resolved in the NMR spectra and could be assigned. Shown are the average ratios and error bars for standard deviations from triplicate experiments. B, residues protected from solvent exchange by Vps75-Rtt109 are color-coded on the surface of the (H3-H4)2 tetramer (from PDB identification code 1EQZ), with the N-terminal tail of H3 in red and residues from the two C-terminal α-helices and interhelical region in yellow (corresponding to a region where H/D exchange ratio values are less than 0.6 for 10 residues).