In situ introduction of positive charge to the inner cavity decreases spermine-dependent rectification. (A–D) Representative currents illustrating rectification induced by spermine in WT-N160D, and in V129C, L157C, and L164C mutant channels (mutation in second half of N160D-N160D dimer background), before and after complete modification by MTSEA+ (modification not shown). Two separate voltage protocols are shown for WT-N160D. One or the other is used for each cysteine mutant construct. Current scale indicates 0.5 nA in each case. (E) Steady-state current in spermine relative to control (Grel) plotted vs. voltage, fitted with Boltzmann functions (no offset) as indicated.
In situ introduction of positive charge to the inner cavity decreases spermine-dependent rectification. (A–D) Representative currents illustrating rectification induced by spermine in WT-N160D, and in V129C, L157C, and L164C mutant channels (mutation in second half of N160D-N160D dimer background), before and after complete modification by MTSEA+ (modification not shown). Two separate voltage protocols are shown for WT-N160D. One or the other is used for each cysteine mutant construct. Current scale indicates 0.5 nA in each case. (E) Steady-state current in spermine relative to control (Grel) plotted vs. voltage, fitted with Boltzmann functions (no offset) as indicated.
