PIK3, or Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit gamma, is a human gene encoded by PIK3CG. It may also be known as: Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit gamma isoform; PI3-kinase subunit gamma; PI3K-gamma; PI3Kgamma; PtdIns-3-kinase subunit gamma; Phosphatidylinositol 4,5-bisphosphate 3-kinase 110 kDa catalytic subunit gamma; PtdIns-3-kinase subunit p110-gamma; p110gamma; Phosphoinositide-3-kinase catalytic gamma polypeptide; Serine/threonine protein kinase PIK3CG; p120-PI3K; PI3CG; phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit gamma. The encoded protein is an enzyme with an amino acid length of 1102 and a mass of 126.5 kDa. Other isoforms may exist. PIK3 is a member of the PI3/PI4-kinase family. Homologs of this gene exist in other organisms, including: Mouse, Rat, Zebrafish, Frog, Chicken.