Expression and Purification of PI3 Kinase alpha and Development of a Luminometric

Human class Ia PI3 kinase p110alpha catalytic and p85alpha regulatory subunits were expressed and purified. A luminometric ATP depletion assay to measure PI3K activity was established and optimized. Furthermore, the autophosphorylation status of PI3K alpha was checked and the IC50 value for the known PI3K inhibitor wortmannin was determined. The assay is homogenous and is potentially suitable for high throughput screening to identify PI3K inhibitors.