The expression of Bcl-2 family proteins at the whole cell level and subcellular distribution. Resting CEM and CEM/VLB₁₀₀ cells were dissolved with 1% Triton X-100 containing lysis buffer. Protein extract (50 μg/lane) was loaded on to 12% SDS-PAGE, transferred to nitrocellulose membrane, and probed with indicated anti–Bcl-2 family protein antibodies. β-Actin served as protein quality control with each experiment. The density of each band was analyzed by densitometry. For whole cell lysate, the ratio CEM:CEM/VLB₁₀₀ for Bcl-X_S = 29:71 (1:2.4); ratio CEM:CEM/VLB₁₀₀ for Bad = 38:62 (1:1.6). For mitochondria protein, ratio CEM:CEM/VLB₁₀₀ for Bcl-X_S = 3:97 (1:32); ratio CEM:CEM/VLB₁₀₀for Bad = 38:62 (1:1.6); ratio CEM:CEM/VLB₁₀₀ for Bax = 12:88 (1:7.3). For the cytosol proteins, ratio CEM:CEM/VLB₁₀₀ for Bax = 62:38 (1.6:1).