Effect of NEM on G317C channels. (A) The addition of 10 mM NEM to the trans compartment leads to a 95% decrease in current with no effect on gating. (B) Current trace before exposure to NEM depicted by dotted line; trace obtained 3 min after exposure is superimposed at the same scale (solid black line) and after normalizing to the peak current at −60 mV before reaction (gray line) to emphasize lack of effect on gating.