Figure 2.
Conserved αCys-263 in the finger domain is proximal to the finger–thumb domain interface. Mutant or wildtype α subunits with wildtype β and γ subunits were expressed in Xenopus oocytes, and currents were measured by two-electrode voltage clamp at −100 mV. Oocytes were treated with 4 μm Cu-Phe for 15 s, followed by 110-Na buffer for 60 s and 10 mm DTT for 60–90 s. A and B, representative recordings. C, inhibition by Cu-Phe was determined by comparing the amiloride-sensitive current at the end of Cu-Phe washout with the amiloride-sensitive current before the addition of Cu-Phe. Bars, mean of each group. *, p < 0.05; **, p < 0.01 versus wildtype by Kruskal–Wallis rank sum test (p < 0.0001) followed by Dunn test for multiple comparisons with p values adjusted with the Benjamini–Hochberg method. NS, not significant.