Time-Resolved Fluorescence-based Lanthascreen Assay: Kinase inhibition assays (10 μL) were performed at 20° C. in 384-well plate format. Compound IC50 values were determined at the apparent Km for ATP (20 μM) based on a radiometric assay (Invitrogen) using 8 or 10 point curves in duplicate. The final reaction conditions contained 400 nM fluorescein-IkBα substrate (DRHDSGLDSMKDE), 20 μM ATP, 2 nM or 8 nM IKKε or TBK1 kinase respectively, and 3% DMSO in kinase assay buffer consisting of 50 mM HEPES (pH 7.5), 10 mM MgCl, 1 mM EGTA, 0.01% Brij-35.Compound dilutions were prepared from 10 mM DMSO stocks by dilution into DMSO. Compound dilution series were further diluted in kinase assay buffer to give a 12% DMSO stock, the final concentration in the assay being 3% DMSO.The kinase phosphorylation assay was initiated by the addition of the kinase and the reaction was allowed to proceed for 1 h or 2.5 h for IKKε and TBK-1 kinase respectively.
Time-Resolved Fluorescence-based Lanthascreen Assay: Kinase inhibition assays (10 μL) were performed at 20° C. in 384-well plate format. Compound IC50 values were determined at the apparent Km for ATP (20 μM) based on a radiometric assay (Invitrogen) using 8 or 10 point curves in duplicate. The final reaction conditions contained 400 nM fluorescein-IkBα substrate (DRHDSGLDSMKDE), 20 μM ATP, 2 nM or 8 nM IKKε or TBK1 kinase respectively, and 3% DMSO in kinase assay buffer consisting of 50 mM HEPES (pH 7.5), 10 mM MgCl, 1 mM EGTA, 0.01% Brij-35.Compound dilutions were prepared from 10 mM DMSO stocks by dilution into DMSO. Compound dilution series were further diluted in kinase assay buffer to give a 12% DMSO stock, the final concentration in the assay being 3% DMSO.The kinase phosphorylation assay was initiated by the addition of the kinase and the reaction was allowed to proceed for 1 h or 2.5 h for IKKε and TBK-1 kinase respectively.