Phosphoinositide 3 Kinase, Recombinant, Human, p110 alpha, p85alpha (PI3K)

Phosphoinositide 3 Kinase, Recombinant, Bovine, p85 alpha (PI3K) functions as the regulatory subunit of the class IA PI3-kinase isoforms a, b, and d. It contains two SH2 domains that bind to tyrosine-phosphorylated growth factor receptors or substrate adaptor proteins. It also contains a BH (breakpoint cluster region homology) domain that shows GAP activity towards the small GTPases Rab4, Rab5, Cdc42, Rac1 and to a lesser extend towards Rab6 and Rab11. It was shown that PI3Ka catalytic subunit mediated phosphorylation of the p85a adapter reduces the lipid kinase activity of the heterodimer and this gives hints for PI3K-dependent signaling events not requiring production of 3'-phosphorylated phosphoinositides. PI3Ka protein kinase activity has been implicated in IRS-1 serine phosphorylation in insulin-treated adipocytes and in STAT3 and IRS-1 phosphorylation upon activation of the type 1 IFN receptor by IFN-a. Complex of N-terminal FLAG-tagged recombinant full-length human p110 alpha (GenBank Accession No. U79143) and recombinant full length, human p85alpha (no tag) (XM_043865). Coexpressed in a Baculovirus infected Sf9 cell expression system. p110 alpha MW=129kD, p85 alpha MW=88kD. , p110 alpha MW 129kD, p85 alpha MW 88kD. Applications: Useful for the study of enzyme kinetics, screening inhibitors, and selectivity profiling. Other applications not tested. Recommended Dilutions: Optimal dilutions to be determined by the researcher. Assay Conditions: A 50ul kinase reaction is conducted in a buffer containing 40mM Tris-HCl pH 7.5, 20mM MgCl2, 100uM ATP, 200uM PI:PS substrate and 20-100ng P4073-26C for 30 min at 30°C. Detection reagent for 55 minutes. Specific Activity: ~600pmol/min/ug, Storage and Stability: For long-term storage, aliquot to avoid repeated freezing and thawing and freeze at -70°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Aliquots are stable for 6 months. ,