Fluorescence Polarization Assay (FPA): The assays were performed in black flat-bottom 384-well plates. The final assay volume was 50 μl prepared from additions of Gst-Bcl-2 (Bcl-2: GENBANK® Accession No. P10415), fluoresceinated 18-mer BIM peptide (NH2-YYANFEDGIRRLEQAIWI-[FAM]) (SEQ ID NO: 1), and test compounds in assay buffer consisting of 20 mM Sodium Phosphate, 1 mM EDTA, 50 mM NaCl, and 0.05% Pluronic Acid. The reaction was incubated at room temperature for 60 minutes and fluorescence polarization of the reaction was detected on the LJL Plate Reader. Inhibition data were calculated from mP values generated by the no protein control reactions for 100% inhibition and vehicle-only reactions for 0% inhibition. The final concentrations of reagents in the assay were 4.9 nM BCL-2, 5 nM fluoresceinated 18-mer BIM peptide and 1% DMSO.
Fluorescence Resonance Energy Transfer Assay (FRET): The assays were performed in black flat-bottom 384-well plates. The final assay volume was 55 μl prepared from additions of Biotin-Bcl-xL (Bcl-xL: GENBANK® Accession No. Q07817), fluoresceinated 18-mer BIM peptide (NH2-YYANFEDGIRRLEQAIWI-[FAM]) (SEQ ID NO: 1), Streptavidin-Terbium FRET detection reagent, and test compounds in assay buffer consisting of 20 mM Sodium Phosphate, 1 mM EDTA, 50 mM NaCl, and 0.05% Pluronic Acid. The reaction was incubated at room temperature for 60 minutes. After 60 minutes, 5 μL of Streptavidin-Terbium FRET detection reagent (Perkin Elmer) was added to the reaction mixture and incubated at room temperature in the dark for 30 mins. The FRET signal generated by the reaction was detected on the Envision Plate Reader Inhibition data were calculated from FRET values generated by the no protein control reactions for 100% inhibition and vehicle-only reactions for 0% inhibition. The final concentration of reagents in the assay was 10 nM Bcl-xL, 5 nM fluo