Inhibition of NIK in human HT-29 cells assessed as LTalpha/beta2-induced p100 processing to NFkappaB2 preincubated for 30 mins before LTalpha/beta2 stimulation measured after 5 hrs
Inhibition Assay: The ability of the nuclear factor-kappa B (NF-kB)-inducing kinase (NIK) to catalyze the hydrolysis of adenosine-5'-triphosphate (ATP) was monitored using the Transcreener ADP (adenosine-5'-diphosphate) assay (BellBrook Labs). Purified NIK (0.2-1 nM) derived from a baculovirus-infected insect cell expression system was incubated with test compounds for 1-3.5 hours in 50 mM 2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid buffer (pH 7.2) containing 10 mM MgCl.sub.2, 2 mM dithiothreitol, 10 uM ATP, 0.01% Triton X-100, 0.1% gamma-globulins from bovine blood, 1% dimethylsulfoxide (DMSO), 12 ug/mL ADP antibody and 4 nM ADP-AlexaFluor.RTM. 633 tracer. Reactions were quenched by the addition of 20 mM 2,2',2'',2'''-(ethane-1,2-diyldinitrilo)tetraacetic acid and 0.01% Brij 35. The tracer bound to the antibody was displaced by the ADP generated during the NIK reaction, which causes a decrease in fluorescence polarization that was measured by laser excitation.
Inhibition of wild-type human partial length NIK (L318 to P947 residues) expressed in mammalian expression system assessed as residual activity at 1 uM by Kinomescan method relative to control