Assay Report Card

ID: ALA3707675

Type: Binding

Description: Fluorescence Resonance Energy Transfer (FRET) Assay: The enzyme inhibitory activity of test compounds was determined by fluorescence resonance energy transfer (FRET) using synthetic peptides labelled with both donor and acceptor fluorophores (Z-LYTE, Invitrogen). Recombinant, phosphorylated p38 MAPK (MAPK12:Millipore) was diluted in HEPES buffer, mixed with compound at the desired final concentrations and incubated for 2 hr at RT. The FRET peptide (2 uM) and ATP (100 uM) were next added to the enzyme/compound mixture and incubated for 1 hr. Development reagent (protease) was added for 1 hr prior to detection in a fluorescence microplate reader. The site-specific protease only cleaves non-phosphorylated peptide and eliminates the FRET signal. Phosphorylation levels of each reaction were calculated using the ratio of coumarin emission (donor) over fluorescein emission (acceptor) with high ratios indicating high phosphorylation levels and low ratios indicating low phosphorylation levels.

Organism: Homo sapiens