FIGURE 7. The C-terminal Domain of Kir2.1 Mediates the Potentiating Effect of Rac1_DN.

A) Schematic of different Kir2.1/2.2 chimeric channels. 2.1_N-2.2, the N terminus of Kir2.1 fused to Kir2.2 at position 78. 2.2_N-2.1, Kir2.1 fused to Kir2.2 at position 121. B) Representative current traces from 2.1_N-2.2 transfected cells under control conditions or co-transfected with Rac1_DN. Superimposed current traces are shown for 200 ms voltage steps from -120 to -20 mV in 10 mV increments from a holding potential of -60 mV. C) Left Current-voltage traces of 2.1_N-2.2 under control conditions (filled squares) or co-transfected with Rac1_DN (open squares). Right: Normalized current densities measured in 2.1_N-2.2 transfected cells under control conditions and co-transfected with Rac1_DN, at –100 mV. D) Representative current traces from 2.2_N-2.1 transfected cells under control conditions or co-transfected with Rac1_DN. Scale bars: 50 ms and 250 pA. E) Left: Current-voltage traces of 2.2_N-2.1 under control conditions (filled squares) or co-transfected with Rac1_DN (open squares). Right: Normalized current densities measured in 2.2_N-2.1 transfected cells under control conditions and co-transfected with Rac1_DN, at -100 mV. Numbers above columns indicate number of cells in each condition. Asterisks denote significance with non-parametric t-tests, (p<0.05).