CHEMBL3706336

Inhibition Assay: A partial protein of only a kinase domain of RET protein was purchased from Carna Biosciences Inc., Japan. The phosphorylation activity toward a peptide substrate was investigated using an EZ reader (Caliper). Test compounds were each mixed with a protein solution to give 8 final concentrations from 100 nM to 0.03 nM, followed by addition of a mixed liquid of ATP and substrate peptide (Caliper) and reaction for 30 minutes. The ATP concentration used was 100 µM. A reaction liquid which contained protein but no test compound (in which the solvent DMSO alone was added at 0.8% in place of the test compound) was prepared, followed by reaction in the same manner with or without ATP addition. In the absence of the test compound, the phosphorylation peptide peak without ATP addition and with ATP addition was assumed to be 100% inhibition and 0% inhibition, respectively.