Phospholipase D and membrane traffic - Potential roles in regulated exocytosis, membrane delivery and vesicle budding

It is now well-established that phospholipase D is transiently stimulated u pon activation by G-protein-coupled and receptor tyrosine kinase cell surfa ce receptors in mammalian cells. Over the last 5 years, a tremendous effort has gone to identify the major intracellular regulators of mammalian phosp holipase D and to the cloning of two mammalian phospholipase D enzymes (pho spholipase D1 and D2). In this chapter, we review the physiological functio n of mammalian phospholipase D1 that is synergistically stimulated by ADP r ibosylation factor, Rho and protein kinase Ca. We discuss the function of t his enzyme in membrane traffic, emphasising the possible integrated relatio nships between consumption of vesicles in regulated exocytosis, membrane de livery and constitutive membrane traffic. (C) 1999 Elsevier Science B.V, Al l rights reserved.