Assay Method Information

Assay Name:  Measurement of Inhibitory Activity Against RET (V804L, V804M)
Description:  Regarding the conditions for measurement of in vitro inhibitory activity of compounds against RET (V804L or V804M) (i.e., RET with V804L or V804M mutation) kinase activity, the website of AnaSpec states that Srctide (GEEPLYWSFPAKKK) corresponds to the substrate peptide for reaction to measure RET kinase activity. Thus, the amino acid sequence was partly modified and biotinylated to prepare biotinylated peptides (biotin-EEPLYWSFPAKKK). The purified recombinant human RET (V804L or V804M) protein used in the test was purchased from Eurofins.To measure the inhibitory activity, first, the test compounds were individually diluted with dimethyl sulfoxide (DMSO) stepwise. Subsequently, RET (V804L or V804M) protein, the substrate peptides (the final concentration: 250 nM), magnesium chloride (the final concentration: 10 mM), ATP (the final concentration: 10 μM), and a solution of a test compound in DMSO (the final concentration of DMSO: 5%) were added to a buffer for kinase reaction (13.5 mM Tris, pH of 7.5, 2 mM dithiothreitol, 0.009% Tween-20). Each of the mixtures was incubated at 25° C. for 120 minutes to perform a kinase reaction. EDTA was then added thereto to give a final concentration of 40 mM so that the reaction was terminated. A detection solution containing Eu-labeled antiphosphotyrosine antibody PT66 (PerkinElmer) and SureLight APC-SA (PerkinElmer) was added thereto, and each mixture was allowed to stand at room temperature for 2 hours or more. Finally, the intensity of fluorescence under excitation light with a wavelength of 337 nm was measured with a PHERAstar FS (BMG Labtech) at the two wavelengths of 620 nm and 665 nm. The phosphorylation level was calculated from the ratio of the fluorescence intensity at the two wavelengths, and the compound concentration at which phosphorylation was inhibited by 50% was defined as the IC50 value (nM).
Affinity data for this assay
 

If you find an error in this entry please send us an E-mail