CHEMBL5730175

Fluorescence Polarization (FP) Assay: Experiments were performed in 96-well Microfluor 2 black plates (Waltham, Mass.), and the samples were read by a Synergy 2 plate reader (Biotek, Winooski, Vt.). The fluorescence polarization (FP) was measured at room temperature with an excitation wavelength at 485 nm and an emission wavelength at 535 nm. The FP saturation experiment was performed in an assay buffer of 137 mM of NaCl, 2.7 mM of KCl, 10 mM of Na2HPO4, 2 mM of KH2PO4, 100 ug/mL of bovine gamma globulin, and 0.01% Triton-X 100. The final reaction volume is 100 uL. The competitive FP assays used 2.5 nM of Tcf4 fluorescence tracer, 10 nM of β-catenin, and different concentrations of the tested inhibitors in 100 uL of assay buffer. Each assay plate was covered black and gently mixed on an orbital shaker for 3 h to reach equilibrium before polarization values were read. For each inhibitor competition assay, the negative controls (equivalent to 0% inhibition) refer to 2.5 nM of Tcf4 fluorescence tracer and 10 nM of β-catenin, but no tested peptide inhibitor was presented. The positive controls (equivalent to 100% inhibition) refer to only 2.5 nM of Tcf4 fluorescence tracer in a final volume of 100 uL.