Fig. 3.
(A) Fluorescence response and gating currents of H486Anap in response to pulses from −90 mV to potentials between −140 and 150 mV. (B) Fluorescence voltage (FV, red circles), gating charge voltage (QV, black squares), and conductance voltage (GV, blue triangles) relations of H486Anap. QV and GV were fitted to Boltzmann relations (QV: V1/2 = −47.2 mV, dV = 16.2 mV; GV: V1/2 = 75.7mV, dV = 20.9 mV). The FV was fitted to a sum of two Boltzmann relations (V1/2,1 = 0.5 mV, dV1 = 14.2 mV, V1/2,2 = 75.7 mV, dV2 = 16.4 mV. (C) Comparison of time dependence between conductance (black) and fluorescence (red) of H486Anap. Fluorescence changes are observed in the absence of ion conduction and clearly precede ion conduction at −20 mV and +40 mV, respectively.