FIGURE 5.

Interaction between BAK and MCL-1 in the presence of IGEPAL. A, Coomassie-stained SDS-gels showing the supernatant (top) and proteins retained by the Ni²⁺-NTA resin (bottom) under the conditions indicated. Conditions 1–3, respectively, mean that cMCL-1, FLAG-BAK-HMK-His₆, or their combination was loaded. Arrows labeled A show the position of FLAG-BAK-HMK-ΔTM-His₆, and arrows labeled B show the position of cMCL-1. The red frame highlights the cMCL-1 retained by FLAG-BAK-HMK-ΔTM-His₆ in the presence of IGEPAL. B, ¹H-¹⁵N HSQC spectra of ¹⁵N-labeled cMCL-1 in 0.1% IGEPAL without (black) and with (red) unlabeled cBAK.