Class I Phosphatidylinositol 3-Kinases

**Definition:** A phosphatidylinositol 3-kinase subclass that includes enzymes with a specificity for 1-phosphatidylinositol, 1-phosphatidylinositol 4-phosphate, and 1-phosphatidylinositol 4,5-bisphosphate. Members of this enzyme subclass are activated by cell surface receptors and occur as heterodimers of enzymatic and regulatory subunits.

**Tree numbers:** - D08.811.913.696.620.500.100.100 - D08.811.913.696.620.500.200.100 - D12.776.476.556.100.100 - D12.776.476.556.200.100

**Synonyms:** - Phosphatidylinositol 3-Kinase, Class I - Class I Phosphatidylinositol 3-Kinase