Fig. 4.

Gβγ inhibition abolishes Kv7.4 currents without change in PIP₂ levels. A In-cell Western analysis showing influence of Gβγ inhibitors on PIP₂ level in HEK293 Kv7.4 cells (n = 11–22). B Mean I-V relationships of HEK293 Kv7.4 currents evoked from holding potential −60 mV before and after application of M201 (50 μM). C Mean data for the effect for mechanistically different inhibitors of Gβγ on whole-cell K⁺ currents recorded at +20 mV (n = 5–7). D Representative inside-out patch recording showing inhibitory action of 50 μM M201 on single channel activity. Subpanels b and c are representative 1.5-s segments of channel openings before and after drug application taken from long-term recording (a). Closed and open states are denoted by C and O1. E Representative inside-out patch recording showing inhibitory action of 10 μM Grk2i on single channel activity. Subpanels b and c are expanded 2.8-s segments of channel openings before and after drug application taken from long-term recording (a). Closed state and multiple open states are denoted by C and O1–O3. F Mean apparent open probability for Kv7.4 channels in control conditions (green column, n = 14) and after application of three different Gβγ inhibitors, M201, gallein and Grk2i (n = 4–6)