2.5. Protein complex immunoprecipitation

Following the indicated drug treatments, cells were lysed with modified RIPA buffer (50 mM Tris‐HCl, 1% NP‐40, 0.25% Na deoxycholate, 150 mM NaCl, 1 mM ethylenediaminetetraacetic acid). Protein (250 µg) was incubated overnight with rotation with 2.5 µg of indicated antibodies (Cell Signaling Technology): BIM (2933), BCL‐xL (2764), or MCL‐1 (94296). Immunocomplexes were recovered with 20 µL protein G agarose beads (Cell Signaling Technology). Protein complexes were separated and solubilized by boiling in 2× Laemmli buffer.