Fig. 3

Mcl-1 inhibits Bim BH3-dependent oligomerization of Bak, which is overcome by obatoclax and Noxa BH3. a Bim BH3 but not Noxa BH3 nor obatoclax induce Bak oligomerization. Bak was conjugated onto liposomes and the liposomes treated with the indicated concentration of BH3 peptides or obatoclax or vehicle (1 % DMSO, lane 1). Liposome-conjugated Bak proteins were crosslinked with 0.5 mM BS³ and the samples analyzed by immunoblot with anti-Bak antibody. Migration of molecular weight markers is indicated. (*) denotes oligomers of Bak. b, c Mcl-1 (3-fold molar excess over Bak) inhibits Bim BH3-induced Bak oligomerization. Treatments and analysis were as in (a), in the presence of Noxa BH3 (b) or obatoclax (c) or vehicle alone, as indicated. Shown are representative blots from at least 3 independent experiments