PI3K plays a specific role in apoptosis in human colon cancer cells. Injection of neutralizing antibodies specific to PI3K into adenocarcinoma cells induced apoptosis, a response that was reverted by treating cells with caspase inhibitor It was also shown that PI3K mediatedphosphorylation of the p85 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. PI3K is a key regulator of the initiation of keratinocyte differentiation
A decrease in PI3K activity results in a loss of keratinocyte adhesion to the extracellular membrane and the initiation of early phase differentiation. The PI3K catalytic and regulatory subunits are coexpressed in Sf9 insect cells.
Phosphoinositide 3-kinases (PI3Ks) phosphorylate phosphatidylinositols (PIs) at their 3´-OH position generating lipid second messengers and thereby regulate numerous biological processes including cell growth, differentiation, survival, proliferation, migration and metabolism. On the basis of structural similarities and substrate specificity, the PI3K family can be subdividedinto three classes termed I, II, and III. All human class I members are heterodimers consisting of a catalytic subunit (MW approx. 110kD) and a noncatalytic subunit (MW 50, 55, 85, or 101kD) and are known to phosphorylate phosphatidylinositol (PI), phosphatidylinositol-4-mono-phosphate (PIP) and phosphatidylinositol-4,5-bisphosphate (PIP2) in vitro. The class I members can be further subdivided into class IA and IB PI3Ks. Class IA exists in three isoforms (p110, p110 and p110 ) whereas the only class IB member is termed p110. Class IA PI3Ks are activated by adaptor proteins such as Ras or BCAP, or tyrosine-kinase-associated receptors including antigen, co-stimulatory and cytokine receptors (e.g. CD19, CD28, Insulin receptor, EGFR, and PDGFR). p110 is activated by G-protein-coupled receptors (GPCRs). Effectors of class I PI3Ks are pleckstrin-homology domain proteins such as Akt/PKB, BTK, TEC, ITK, BAM32, and small GTPases (e.g. Cdc42, Rac, or Ras). The action of PI3Ks is regulated by the phosphatidylinositol-3,4,5-trisphosphate phosphatases SHIP and PTEN.
Source:Recombinant corresponding to complex of N-terminal FLAG-tagged recombinant full-length human p110a, with E545K mutation, and recombinant full length human p85a co-expressed in Sf9 cells in a Baculovirus expression system.
Applications:Suitable for use in the study of enzyme kinetics, screening inhibitors, and selectivity profiling. Other applications not tested.
Recommended Dilution:Optimal dilutions to be determined by the researcher.
Specific Activity:~800pmol/min/ug
Storage and Stability:Aliquot to avoid repeated freezing and thawing and store at -70°C. Aliquots are stable for 6 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
仕様
Size:20ug
Source Antigen:Recombinant, Sf9 insect cells
Grade:Purified
Purity:Purified (~55%)
Form:Supplied as a liquid in 40mM Tris, pH 8.0, 110mM sodium chloride, 2.2mM potassium chloride, 20% glycerol, 3mM DTT.