BindingDB logo
myBDB logout

Assay Method Information

Assay Name:  TR-FRET ASK1 kinase assay
Description:  The assay measures the phosphorylation level of a biotinylated peptide substrate by the ASK1 kinase using HTRF detection (6.1). This is a competitive, time-resolved fluorescence resonance energy transfer (TR-FRET) immunoassay, based on HTRF KinEASE -STK manual from Cisbio (6.1). Test compound, 1 μM STK3 peptide substrate, 4 nM of ASK1 kinase are incubated with 10 mM MOP buffer, pH. 7.0 containing 10 mM Mg-acetate, 0.025% NP-40, 1 mM DTT, 0.05% BSA and 1.5% glycerol for 30 minutes then 100 μM ATP is added to start the kinase reaction and incubated for 3 hr. Peptide antibody labeled with 1×Eu3+ Cryptate buffer containing 10 mM EDTA and 125 nM Streptavidin XL665 are added to stop the reaction and phosphorylated peptide substrate is detected using Envision 2103 Multilabeled reader from PerkinElmer. The fluorescence is measured at 615 nm (Cryptate) and 665 nm (XL665) and a ratio of 665 nm/615 nm is calculated for each well. The resulting TR-FRET level (a ratio of 665 nm/615 nm) is proportional to the phosphorylation level. Under these assay conditions, the degree of phosphorylation of peptide substrate was linear with time and concentration for the enzyme. The assay system yielded consistent results with regard to Km and specific activities for the enzyme. For inhibition experiments (IC50 values), activities were performed with constant concentrations of ATP, peptide and several fixed concentrations of inhibitors. Staurosporine, the nonselective kinase inhibitor, was used as the positive control. All enzyme activity data are reported as an average of quadruplicate determination.
Affinity data for this assay
 

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

Home

|

Search

|

Deposit

|

SiteMap

|

About us

|

Email us

|

Info

 
Last update November 1, 2007
©2000 BindingDB. All rights reserved.