Fig. 5. Conformational changes at the electromechanical coupling interface.

a, b Structures of the transmembrane region corresponding to the Closed (a) and Open (b) conformations. S4 and S5 helices are either sky blue (Closed state) or salmon (Open state). Residues I284 and V296 (denoted as spheres) demarcate the intracellular gating interface (in yellow) that undergoes helix coil. c Superposition showing the side view of S1–S5 helices of the Closed (sky blue) and Open (salmon) states. The P-loop and the S6 transmembrane helices were removed for clarity. Structures were aligned to helices S1 and S2.