Figure 2. Rate–equilibrium (R–E) plots for mutations of loop 9 in the α subunit.

f₂ is the forward, channel-opening rate constant (s⁻¹) and E₂ is the diliganded gating equilibrium constant. Values have been normalized by the wt value (filled circles). In each panel, the x-axis range reflects the mutational sensitivity of the position with regard to E₂. Only positions 174, 175 and 176 show significant changes in gating upon mutation.