| Assay Method Information | |
| | SMYD3 Enzyme Assays on MEKK2 Protein Substrate |
| Description: | The assays were an performed in a buffer consisting of 25 mM Tris-Cl pH 8.0, 1 mM TCEP, 0.005% BSG, and 0.005% Tween 20, prepared on the day of use. Compounds in 100% DMSO (1 ul) were spotted into a 384-well white opaque OptiPlate using a Bravo automated liquid handling platform outfitted with a 384-channel head (Agilent Technologies), DMSO (1 ul) was added to Columns 11, 12, 23. 24, rows A-H for the maximum signal control and 1 ul of SAH, a known product and inhibitor of SMYD3, was added to columns 11, 12, 23, 24, rows I-P for the minimum signal control. A cocktail (40 ul) containing the SMYD3 enzyme was added by Multidrop Combi (Thermo-Fisher). The compounds were allowed to incubate with SMYD3 for 30 min at room temperature, then a cocktail (10 ul) containing SAM and MEKK2 was added to initiate the reaction (final volume=51 ul). The final concentrations of the components were as follows: SMYD3 was 0.4 nM, 3H-SAM was 8 nM, MEKK2 was 12 nM, SAH in the minimum signal control wells was 1 mM, and the DMSO concentration was 2%. The assays were stopped by the addition of non-radiolabeled SAM (10 ul) to a final concentration of 100 uM, which dilutes the 3H-SAM to a level where its incorporation into MEKK2 is no longer detectable. Radiolabeled MEKK2 was detected using a scintillation proximity assay (SPA). 10 uL of a 10 mg/mL solution of SPA beads in 0.5 M citric acid was added and the plates centrifuged at 600 rpm fort min to precipitate the radiolabeled MEKK2 onto the SPA beads. The plates were then read in a PerkinElmer TopCount plate reader to measure the quantity of 3H-labeled MEKK2 as disintegrations per minute (dpm) or alternatively, referred to as counts per minute (cpm).% inhibition calculation % inh = 100 - ( dpm cmpd - dpm min dpm max - dpm min ) × 100Where dpm=disintegrations per minute, cmpd=signal in assay well, and min and max are the respective minimum and maximum signal controls.Four - parameter IC 50 fit Y = Bottom + ( Top - Bottom ) ( 1 + ( X IC 50 ) Hill CoefficientWhere top and bottom are the normally allowed to float, but may be fixed at 100 or 0 respectively in a 3-parameter fit. The Hill Coefficient normally allowed to float but may also be fixed at 1 in a 3-parameter fit. Y is the % inhibition and X is the compound concentration. |
| Affinity data for this assay | |
|---|---|
| If you find an error in this entry please send us an E-mail | |