Function as phospholipase selective for phosphatidylcholine (PubMed:21085684). May have a role in signal-induced cytoskeletal regulation and/or endocytosis (PubMed:9395408). a 1,2-diacyl-sn-glycero-3-phosphocholine + H2O = a 1,2-diacyl-sn-glycero-3-phosphate + choline + H(+) 1,2-dihexadecanoyl-sn-glycero-3-phosphocholine + H2O = 1,2-dihexadecanoyl-sn-glycero-3-phosphate + choline + H(+) Stimulated by phosphatidylinositol 4,5-bisphosphate. Is not responsive to either ADP-ribosylation factor-1 (ARF-1) or GTP-binding proteins such as RHOA. Optimum pH is 7.4. Interacts with PIP5K1B (By similarity). Interacts with EGFR (PubMed:9837959). At least 3 isoforms are produced. Ubiquitous. Highest levels in brain and lung. Expressed at high levels in the hippocampus at the earliest time at which it is defined as a structure and also in ventricular neural cells as well as differentiating neurons outside of the ventricular region. Expressed during development in lower levels in mesenchymal cells derived from the neural crest that are destined to form bones of the skull. Phosphorylated by FGR (By similarity). Phosphorylated on Tyr-11; most likely by EGFR (PubMed:9837959). Belongs to the phospholipase D family.