U.S. National Library of Medicine

1. 1-Phosphatidylinositol 3-Kinase

   An enzyme that catalyzes the conversion of phosphatidylinositol to phosphatidylinositol 3-phosphate. This is the first committed step in the biosynthesis of phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate. This pathway is thought to play a critical role in DNA repair, V(D)J recombination and cell cycle checkpoints. EC 2.7.1.137.