Fig. 5. Influence of KCNQ1 pore domain mutations on the DIDS-mediated slowdown of KCNQ1/KCNE1 channel deactivation. A. Effect of 10 µM DIDS on deactivation kinetics of wildtype and mutant KCNQ1/KCNE1 channels. τ_deactivation was calculated by fitting deactivation traces to a single exponential function (Q1 wt n = 7-11; S333A n = 5-10; V334A n = 3-6; F335A n = 12-22; A336C n = 7-20; I337A n = 11-28; S338A n = 4-7, ± SEM). Representative currents are shown as small inlay representations. Currents were recorded using the deactivation protocol (3) described in methods section. B. Table of deactivation effects by 10 µM DIDS of wildtype and mutant KCNQ1/KCNE1 channels.