Nav1.9-BAD-GFP channels produce currents comparable with untagged Nav1.9 channels.
A, schematic representation of the Nav1.9-BAD-GFP construct showing locations of the BAD (orange loop) and the C-terminal GFP tag (green star). The BAD domain is biotinylated by a co-transfected bacterial biotin ligase, BirA, which allows channel detection using a streptavidin-conjugated fluorophore CF-640R (red star). B, representative current traces recorded from superior cervical ganglion neurons expressing either Nav1.9 (green) or Nav1.9-BAD-GFP (gray). C, comparison of voltage dependence of activation for Nav1.9 (green, n = 9) and Nav1.9-BAD-GFP (gray, n = 8) channels. D, comparison of voltage dependence of steady-state fast inactivation for Nav1.9 (green, n = 9) or Nav1.9-BAD-GFP (gray, n = 8) channels. Error bars, S.E.