Single-channel conductance of D964K, E994Q, and H958Q. (A–D) Representative recordings of single-channel openings of WT TRPM2, D964K, E994Q, and H958Q at +80 mV in inside-out patches. The external (pipette) solution was normal Tyrode's solution; the internal (bath) solution was nominal Ca²⁺-free solution with 200 µM ADPR. (E–H) Single-channel conductances obtained by linear regression of single-channel current amplitude at the indicated voltages. The conductance is 59.9 ± 1.0 pS for D964K (n = 8), 49.5 ± 0.4 pS (n = 4) for E994Q, and 57.8 ± 1.1 pS (n = 4) for H958Q.