Phospholipid signaling in leukocytes.
Major advances have been made recently concerning mechanisms involved in the generation of second messengers derived from agonist-induced phospholipid metabolism. New functions for well-known GTPases have been described, and other well-characterized proteins have been identified as regulators of phospholipases and phosphokinases. ARF and Rho have been recently identified as activators of phospholipase D. Rho regulates not only phospholipase D but also phosphatidylinositol 4-phosphate 5-kinase. Both beta gamma- and alpha-subunits of heterotrimeric G-proteins have been described as regulators of a new isoform of phosphatidylinositol kinase. Phosphatidylinositol transfer protein is now recognized as an essential requirement for both phospholipase C gamma and C beta isozymes to hydrolyze phosphatidylinositol 4,5-bisphosphate in cells. Some of these proteins such as ARF, Rho, and phosphatidylinositol transfer protein have well-defined roles in vesicular traffic and in cytoskeletal reorganization, thus bringing the field of signal transduction closer to the world of vesicular traffic as well as the cytoskeleton.
Cockcroft
S
S
Department of Physiology, University College London, UK.
D019870:1-Phosphatidylinositol 4-Kinase / Q000502:physiology; D002352:Carrier Proteins / Q000502:physiology; D003599:Cytoskeleton / Q000502:physiology; D020558:GTP Phosphohydrolases / Q000502:physiology; D019204:GTP-Binding Proteins / Q000502:physiology; D007962:Leukocytes / Q000502:physiology*; D008565:Membrane Proteins; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000096:biosynthesis; D010739:Phospholipase D / Q000502:physiology; D049294:Phospholipid Transfer Proteins; D010743:Phospholipids / Q000502:physiology*; D011493:Protein Kinase C / Q000502:physiology; D015398:Signal Transduction
D002352:Carrier Proteins; D008565:Membrane Proteins; D019269:Phosphatidylinositol 4,5-Diphosphate; D049294:Phospholipid Transfer Proteins; D010743:Phospholipids; D019869:Phosphatidylinositol 3-Kinases; D019870:1-Phosphatidylinositol 4-Kinase; D011493:Protein Kinase C; D010739:Phospholipase D; D020558:GTP Phosphohydrolases; D019204:GTP-Binding Proteins