Function as phospholipase selectivefor phosphatidylcholine (PubMed:9395408). Implicated as a critical step in numerous cellular pathways, including signal transduction, membrane trafficking, and the regulation of mitosis. May be involved in the regulation of perinuclear intravesicular membrane traffic (PubMed:9395408). a 1,2-diacyl-sn-glycero-3-phosphocholine + H2O = a 1,2-diacyl-sn-glycero-3-phosphate + choline + H(+) a 1,2-diacyl-sn-glycero-3-phosphocholine + ethanol = 1,2-diacyl-sn-glycero-3-phosphoethanol + choline 1,2-dihexadecanoyl-sn-glycero-3-phosphocholine + H2O = 1,2-dihexadecanoyl-sn-glycero-3-phosphate + choline + H(+) Stimulated by phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate, activated by the phosphokinase C-alpha, by the ADP-ribosylation factor-1 (ARF-1), and to a lesser extent by GTP-binding proteins: RHO A, RAC-1 and CDC42. Inhibited by oleate. Interacts with PIP5K1B. Expressed in kidney, lung, and at a much lower levels, in brain, liver, heart, testis and spleen. Expressed most strikingly in selected ventricular cells lining the spinal cord and brain. The level of expression decreases dramatically as the cells differentiate into neurons and migrate to the outer layer of the spinal cord and brain. Expression is observed during development in a restricted region of the nasal neuroepithelium. Defects in Pld1 may result in coa which is associated with coat color dilution and white spotting. It is also associated with platelet-storage pool deficiency characterized by decreased levels in serotonin and dense granules. Belongs to the phospholipase D family.