Fig. 8. Functional importance of the Leu9′ residue in ZAC.

A. Representative traces for Zn²⁺-evoked currents in ZAC^L9′I-expressing oocytes (top), and averaged concentration-response relationships exhibited by Zn²⁺ at WT ZAC, ZAC^L9′A, ZAC^L9′V, ZAC^L9′I and ZAC^L9′T (means ± S.E.M., n = 6–8) (bottom). B. Resting membrane potentials (left) and leak currents (right) recorded from oocytes expressing WT ZAC, ZAC^L9′A, ZAC^L9′T, ZAC^L9′V and ZAC^L9′I. Data are given as mean ± S.E.M. values (n = 40–60). C. Representative traces for Zn²⁺- and TC (100 μM)-evoked currents in WT ZAC- and ZAC^L9′I-expressing oocytes (top), and averaged current amplitudes evoked by a saturating concentration of Zn²⁺ and by TC (100 μM) in WT ZAC-, ZAC^L9′A-, ZAC^L9′V-, ZAC^L9′I-, and ZAC^L9′T-oocytes (means ± S.E.M., n = 6–8) (bottom). 10 mM Zn²⁺ were used for WT ZAC and 1 mM Zn²⁺ were used for ZAC^L9′A, ZAC^L9′V, ZAC^L9′I and ZAC^L9′T. D. Degrees of spontaneous activity [defined as: I_{100 uM TC}/ (I_{Zn2+ max} + I_{100 uM TC})] (left) and total current amplitude windows (defined as: I_{Zn2+ max} + I_{100 uM TC}) (right) exhibited by WT ZAC, ZAC^L9′A, ZAC^L9′V, ZAC^L9′I and ZAC^L9′T expressed in oocytes.