Supplementary Figure 4: The effects of IbTx on pmBK channel activity and expression.
From: Nuclear BK channels regulate gene expression via the control of nuclear calcium signaling
(a) Outward potassium channel currents were recorded in whole-cell patch clamp to show that paxilline (10 μM) had no additive effect on pmBK channel blockade by IbTx (100 μM). The recording solution contains 1mM 4-AP, 1μM TTX, and 5μM glybenclamide. (b) The effects of IbTx (100 μM) and IbTx (100 μM)+paxilline (10 μM) on action potentials. IbTx broadened the action potential by blocking BK channels. Paxilline did not show additive effects. (c) Pre-incubation (10 min) of IbTx did not affect BK channel expression on plasma membrane. Membrane proteins were isolated as described in Methods section. Na/K ATPase was used as loading control. The full-length blots for c are presented in Supplementary Figure 7.
