Fig. 6.

Effect of imposed potential on manganese- and zinc-induced currents. The oocytes were incubated in medium containing 100 mM Mes (pH 5.5) in the presence or absence of 1 mM MnCl₂ or ZnCl₂. The oocyte membrane was held at –25 mV and stepped to a series of test voltages from +50 mV to –125 mV in steps of 25 mV. The differential currents in the presence and absence of the metal were recorded. (A) DCT1. (B) D124A mutant. (C) D124A + Q126D mutant. Diamonds, ±ZnCl₂; squares, ±MnCl₂.