Current recordings in oocytes expressing mutated hAE1. (A) The representative electric signal of oocytes injected with the different hAE1 mutants following voltage clamp protocol. Oocytes were incubated in MBS. (B) The current-voltage curves of oocytes injected with mutant hAE1 (━) compared with wt hAE1 expressing oocytes (----) are plotted. Presented data are means (± SEM) of n oocytes coming from different batches: n = 10 for L687P; n = 11 for D705Y; n = 15 for S731P; n = 23 for H734R; and n = 21 for wt hAE1. (C) Calculated I/V curves giving the features of the current due to hAE1 point mutations only. These calculated I/V curves were obtained by subtracting the mean basal current of wild-type hAE1-injected oocytes (corresponding to dotted line in panel B) to the mean current induced by expression of hAE1 mutations (corresponding to plain line in panel B).