![]()
|
|
||||||||
J. Biol. Chem., Vol. 265, Issue 9, 4934-4938, 03, 1990
JV Bonventre, JH Gronich and RA Nemenoff
Medical Services, Massachusetts General Hospital, Boston.
We have previously characterized a hormonally regulated soluble form of phospholipase A2 (PLA2) in the cultured renal mesangial cell which is similar and possibly identical to the major form in rat kidney. In an attempt to further characterize the mechanisms of regulation of this enzyme we have used epidermal growth factor (EGF), which does not activate polyphosphoinositide-specific phospholipase C in these cells. EGF-enhanced PLA2 activity as assayed by the ability of the soluble extracts of cells to cleave arachidonic acid from the sn-2 position of phosphatidylcholine and phosphatidylethanolamine. This represents a direct demonstration of EGF-induced PLA2 activation which is preserved in a cell-free extract. Phorbol myristate acetate (PMA), as well as 1- oleoyl-2-acetylglycerol, also enhanced PLA2 activity. By contrast, the calcium ionophore A23187 had no effect on extract PLA2 activity. The EGF- and PMA-induced enhanced activity was recovered following fractionation by Mono-Q anion exchange chromatography. The peak of activity comigrated for both agonists, suggesting that both EGF and PMA stimulated the same form of the enzyme. Down-regulation of protein kinase C by pretreatment with PMA resulted in loss of the PMA-induced, but not the EGF-induced, enhancement in PLA2 activity. 8-Bromo-cAMP had no effect upon the PLA2 activity, and did not modulate the EGF effect. Pertussis toxin induced G protein ADP-ribosylation but had no effect upon PLA2 activity, and did not alter the EGF effect. In summary, EGF results in a stable modification of PLA2 activity in glomerular mesangial cells. This enhanced activity is independent of polyphosphoinositide hydrolysis, insensitive to protein kinase C down- regulation, and is not affected by cAMP or pertussis toxin pretreatment of the cells.
This article has been cited by other articles:
![]() |
S. Placier, X. Bretot, N. Ardaillou, J.-C. Dussaule, and R. Ardaillou Regulation of ANP clearance receptors by EGF in mesangial cells from NOD mice Am J Physiol Renal Physiol, August 1, 2001; 281(2): F244 - F254. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. M. Sheridan, T. Force, H.-J. Yoon, E. O'Leary, G. Choukroun, M. R. Taheri, and J. V. Bonventre PLIP, a Novel Splice Variant of Tip60, Interacts with Group IV Cytosolic Phospholipase A2, Induces Apoptosis, and Potentiates Prostaglandin Production Mol. Cell. Biol., July 15, 2001; 21(14): 4470 - 4481. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. V. BONVENTRE The 85-kD Cytosolic Phospholipase A2 Knockout Mouse: A NewTool for Physiology and Cell Biology J. Am. Soc. Nephrol., February 1, 1999; 10(2): 404 - 412. [Full Text] |
||||
![]() |
S. Harwalkar, C.-H. Chang, N. O. Dulin, and J. G. Douglas Role of Phospholipase A2 Isozymes in Agonist-Mediated Signaling in Proximal Tubular Epithelium Hypertension, March 1, 1998; 31(3): 809 - 814. [Abstract] [Full Text] [PDF] |
||||
![]() |
G Bunt, J de Wit, H van den Bosch, A. Verkleij, and J Boonstra Ultrastructural localization of cPLA2 in unstimulated and EGF/A23187-stimulated fibroblasts J. Cell Sci., January 10, 1997; 110(19): 2449 - 2459. [Abstract] [PDF] |
||||
![]() |
G. Skouteris and C. Schroder Cytosolic phospholipase A2 is activated by the hepatocyte growth factor receptor-kinase in Madin Darby canine kidney cells J. Cell Sci., January 7, 1997; 110(14): 1655 - 1663. [Abstract] [PDF] |
||||
![]() |
J. Wijkander, J. T. O'Flaherty, A. B. Nixon, and R. L. Wykle 5-Lipoxygenase Products Modulate the Activity of the 85-kDa Phospholipase A(2) in Human Neutrophils J. Biol. Chem., November 3, 1995; 270(44): 26543 - 26549. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y Nishizuka Intracellular signaling by hydrolysis of phospholipids and activation of protein kinase C Science, October 23, 1992; 258(5082): 607 - 614. [Abstract] [PDF] |
||||
![]() |
G. S. A. T. van Rossum, R. Klooster, H. van den Bosch, A. J. Verkleij, and J. Boonstra Phosphorylation of p42/44MAPK by Various Signal Transduction Pathways Activates Cytosolic Phospholipase A2 to Variable Degrees J. Biol. Chem., July 27, 2001; 276(31): 28976 - 28983. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |