(A) BH3-only protein tBID directly activates BAX-mediated liposomal release, which is effectively suppressed by treatment with anti-apoptotic MCL-1ΔNΔC and BCL-XLΔC.
(B) MCL-1 SAHBD selectively inhibited MCL-1ΔNΔC suppression of tBID-induced BAX activation.
(C) ABT-737 selectively inhibited BCL-XLΔC suppression of tBID-induced BAX activation.
(D) The activity profile of MIM1 in the liposomal release assay mirrored the MCL-1 selectivity of MCL-1 SAHBD.
Liposomal assays were conducted in triplicate for each condition and repeated with an independent preparation of recombinant BAX with similar results.