Fig. 4.

Correlated motions are identified between residues in the extracellular ligand-binding and intracellular G-protein-coupling sites of the apo M2 receptor. Shown is a dynamic map of color-coded residue cross-correlations for the QNB-bound (lower triangle) and apo (upper triangle) forms of the M2 receptor calculated from the dual-boost aMD simulations. Residues in the TM1 to TM7 helices are indicated by bars on the top and right. Axis breaks correspond to residues 218–376 that are missing in the ICL3 region.