(A) IP3R type 1 single channel recordings at 0 mV in planar lipid bilayers with 250 nM Ca2+ and 2 μM IP3 in the cis (cytosolic) compartment (zero-current level marked). Current traces at the expanded time scale are shown in the bottom panel. Purified Bcl-2 (0.1 μM), added to the cis compartment, blocked channel activity. Subsequent addition of peptide 2 (10 μM) reversed Bcl-2’s inhibition of channel activity.
(B) Shown is a single channel recording documenting that significant reduction of channel activity is detected within less than 3 min after Bcl-2 addition.
(C) Summary of multiple experiments (mean ± SEM) measuring effects of Bcl-2 and peptides on IP3R channel open probability. n = number of individual channels examined. Symbols represent mean ± SEM. *p < 0.05.