ABT-737 exhibits greater potency at displacing BimSΔC from Bcl-2 than from Bcl-xL or Bcl-w. Flp-In T-REx 293 cells with single copy integration of an inducible bicistronic construct expressing mCherry-BimSΔC and eGFP-Bcl-2, Bcl-xL or Bcl-w were imaged live every 25 minutes on treatment of ABT-737 at a 10-point dose range from 5nM to 100μM. (A) Displacement of mCherry-BimSΔC from the mitochondria was measured at 350 minutes after compound addition and normalized to DMSO controls at t = 0. (B) EC50 values were estimated by fitting mitochondrial displacement of mCherry-BimSΔC in response to ABT-737 to sigmoid curves and averaged for 2 to 4 biologic replicates. P values comparing Bcl-2 with Bcl-xL and Bcl-w were .0009 and .028, respectively. Error bars represent SE, and P values were calculated using a Student t test.
