Figure 2.
Nav1.5 variant R104W but not R121W exerts dominant-negative effect over WT channels. (a) Representative whole-cell INa traces recorded from TsA-201 cells transiently transfected with 100% WT Nav1.5, 50% WT + 50% empty vector, 100% R104W, 50% WT + 50% R104W, 100% R121W or 50% WT + 50% R121W. (b) Current density-voltage relationships of the listed conditions. (c) Steady-state inactivation (SSI, left) and activation (right) curves obtained using the Boltzmann equation. Patch clamp protocols are given under the respective curves. (d) Peak current densities of each group under unsaturated condition. Peak current density of WT + R104W is significantly lower than that of WT + empty vector, indicating the dominant-negative effect of R104W over WT channels. Values pertaining to the biophysical properties are shown in Table 2. Data are presented as mean ± SEM. ***, p < 0.001.