Description_x000D_ General description_x000D_ PI3K (p110alpha/p55gamma) or Phosphatidylinositol 3-kinase is a lipid kinase that phosphorylates the inositol ring of phosphatidylinositol at the 3-prime position which serve as second messengers in growth signaling pathways. PI3K comprises a 110 kD catalytic subunit and a regulatory subunit of either 85, 55, or 50 kD. Phosphatidylinositol 3-kinase plays an important role in the metabolic actions of insulin, and a mutation in the PI3K has been associated with insulin resistance and plays an important role in glucose homeostasis in vivo. PI3K also plays an essential role in the development and induction of mast cells in normal and pathogenic immune responses._x000D_ Physical form_x000D_ Supplied in 50 mM sodium phosphate, pH 7.0, 300 mM NaCl, 150 mM imidazole, 0.1 mM PMSF, 0.2 mM DTT, 25% glycerol._x000D_ Preparation Note_x000D_ After opening, aliquot into smaller quantities and store at -70 °C. Avoid repeating handling and multiple freeze/thaw cycles._x000D_ Legal Information_x000D_ PRECISIO is a registered trademark of Sigma-Aldrich Co. LLC