Figure 5.

The full primed mechanism. It is shown for a receptor with two binding sites, such as the nicotinic receptor (Mukhtasimova et al., 2009). The agonist is denoted A. The two binding subunits are shown as R.R when both are in the resting conformation, as R.F when one is primed/flipped (green) and as F.F when both are primed/flipped. Open states (red) are denoted O′ if one subunit is flipped/primed and O′′ if both are. Equilibrium constants for binding are shown in brown, with primes to indicate the number of primed subunits.