Search and Browse
Download
Enter Data
|
Assay Method Information |
|
| | TR-FRET PIK3 Assay |
| Description: | TR-FRET monitored the formation of 3,4,5-inositol triphosphate molecule that competed with fluorescently labeled PIPS for binding to the GRP-1 pleckstrin homology domain protein. An increase in phosphatidylinositide 3-phosphate product resulted in a decrease in TR-FRET signal as the labeled fluorophore was displaced from the GRP-1 protein binding site.Class I PI3K isoforms were expressed and purified as heterodimeric recombinant proteins. All assay reagents and buffers for the TR-FRET assay were purchased from Millipore. PI3K isoforms were assayed under initial rate conditions in the presence of 25 mM Hepes (pH 7.4), and 2× Km ATP (75-500 μM), 2 μM PIP2, 5% glycerol, 5 mM MgCl2, 50 mM NaCl, 0.05% (v/v) Chaps, 1 mM dithiothreitol, and 1% (v/v) DMSO at the following concentrations for each isoform: PI3Kα, PI3Kβ, and PI3Kδ between 25 and 50 pM, and PI3Kγ at 2 nM. The compounds of Table 1 and Compound X ((S)-2,4-diamino-6-((1-(5-chloro-4-oxo-3-phenyl-3,4-dihydroquinazolin-2-yl)ethyl)amino)pyrimidine-5-carbonitrile) were added to the assay solution and incubated for 30 minutes at 25° C. The reactions were terminated with a final concentration of 10 mM EDTA, 10 nM labeled-PIPS, and 35 nM Europium labeled GRP-1 detector protein before reading TR-FRET on an Envision plate reader (Ex: 340 nm; Em: 615/665 nm; 100 is delay and 500 is read window).The results were normalized based on positive (1 μM wortmanin) and negative (DMSO) controls, and the IC50 values for PI3Kα, β, δ, and γ were calculated from the fit of the dose-response curves to a four-parameter equation. These assays generally produced results within 3-fold of the reported mean. |
| 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 |
|
©2000 BindingDB. All rights reserved. |
|||||||||||||