Fig. 5

Mutant channels display biophysical coupling with WT sodium channel. a Steady-state inactivation for the R1629Q mutant and WT expressed in HEK293 cells. The theoretical curve (dotted line) is obtained by averaging the WT and the R1629Q mutant curves together. The dotted line corresponds to the expected theoretical curve if each channel behaved independently. Data show that co-expression of the two channels together does not behave as expected for two independent channels (theoretical curve) and therefore suggests coupling of the two channels. b Steady-state inactivation of WT and R1629Q mutant in HEK293 cells in presence of the 14-3-3 inhibitor difopein. Data show that the steady-state inactivation in presence of difopein now behaves as the theoretical curve for independent channels. Data are presented as mean ± SEM. Right panel displays representative current recordings for each conditions listed