Figure 2.

Structural and mechanistic basis of a potential GPCR voltage sensor as derived by MD simulations. Depolarised V_m drives outward migration of an internal cation bound near D^2.50 towards the extracellular space, crossing the ligand binding pocket. The observed gating charges for this transition are in excellent agreement with experimental values. Upon repolarisation or hyperpolarisation, the cation is attracted back into the allosteric binding pocket. The trajectory of a cation under depolarisation is colour-coded according to the simulation time, proceeding from red to blue.