| Assay Method Information | |
| | Inhibition of SOS1 Nucleotide Exchange Activity |
| Description: | The purpose of this assay was to characterize the inhibitory activity of compounds on SOS1 nucleotide exchange of KRAS. Data was reported as IC50 values based on the TR-FRET signal.Note the Following Protocol Describes a Procedure for Monitoring the Inhibition of SOS1 Nucleotide Exchange Activity of Wild-Type KRAS in Response to a Compound of the Invention. Other KRAS Mutants and RAS Isoforms May be Employed.In assay buffer containing 20 mM HEPES, pH 7.5, 150 mM NaCl, 5 mM MgCl2, 0.05% Tween-20, 0.1% BSA, 1 mM DTT, concentration series of test compounds were generated spanning 100 μM to 1.7 nM over eleven 3-fold serial dilutions in a 384-well assay plate at a volume of 20 μL. The purified tagless catalytic domain of SOS1 (residues 564-1049) was first diluted in assay buffer at a concentration of 100 nM, and then 20 μL of the SOS1 containing solution was directly dispensed into compound plates. The SOS1/compound mixture was incubated at room temperature with constant mixing on an orbital shaker for 20 minutes to allow the reaction to reach equilibrium. A KRAS mixture was prepared by diluting 66.7 nM avi-tagged KRAS (residue 1-169), 3.33 nM Streptavidin-Tb and 333 nM EDA-GTP-DY-647P1 in assay buffer. This mixture was prepared immediately before addition to the SOS1/compound mixture to prevent intrinsic nucleotide exchange. Then 5 μL of the pre-incubated SOS1/compound mixture and 7.5 μL of the KRAS mixture were added sequentially in a 384-well low volume black round bottom plate and incubated at room temperature with constant shaking for 30 minutes. Time-resolved fluorescence was measured on a PerkinElmer Envision plate reader. DMSO and 10 μM of compound (i) were used as negative and positive controls, respectively. |
| Affinity data for this assay | |
|---|---|
| If you find an error in this entry please send us an E-mail | |