Phospholipase D is activated by phorbol ester but not CSF-1 in murine bone marrow-derived macrophages.
Phospholipase D activity was measured in murine bone marrow-derived macrophages (BMM) treated with either colony stimulating factor-1 (CSF-1) or phorbol myristyl acetate (PMA) by measuring formation of phosphatidylbutanol (PtBut) in cells preloaded with n-butanol. Addition of 10(-7) M PMA for 15 min stimulated the amount of PtBut formed in growth arrested cells by 3-4 fold whereas no stimulation was observed with 5000 units mL-1 CSF-1 for 0.5, 2 or 15 min. Protein kinase C activity was determined in growth-arrested BMM by phosphorylation of Myristoylated Alanine-Rich C Kinase Substrate (MARCKS). PMA stimulation for 5 min increased protein kinase C activity 5-6 fold whereas CSF-1 treatment for 5 min or 15 min did not. Contrary to earlier reports, CSF-1 did not stimulate diradyl glycerol formation in BMM. These results show that stimulation of protein kinase C and the activation of phospholipase D are not involved in the early events of CSF-1-stimulated signal transduction pathways in BMM.
Jaworowski
A
A
Department of Medicine, University of Melbourne, Royal Melbourne Hospital, Parkville, Victoria, Australia.
Argyriou
S
S
Yusoff
P
P
Hamilton
J A
JA
D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D003600:Cytosol / Q000201:enzymology; D004075:Diglycerides / Q000378:metabolism; D004789:Enzyme Activation; D020404:Glycerophospholipids; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000201:enzymology; D047908:Intracellular Signaling Peptides and Proteins; D007700:Kinetics; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D008565:Membrane Proteins; D051379:Mice; D008808:Mice, Inbred CBA; D019814:Myristic Acid; D009227:Myristic Acids / Q000378:metabolism; D000076250:Myristoylated Alanine-Rich C Kinase Substrate; D010712:Phosphatidic Acids / Q000032:analysis / Q000378:metabolism; D010739:Phospholipase D / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D004075:Diglycerides; D020404:Glycerophospholipids; D047908:Intracellular Signaling Peptides and Proteins; C000619711:Marcks protein, mouse; D008565:Membrane Proteins; D009227:Myristic Acids; D010712:Phosphatidic Acids; D011506:Proteins; C068564:phosphatidylbutanol; D019814:Myristic Acid; D000076250:Myristoylated Alanine-Rich C Kinase Substrate; D016173:Macrophage Colony-Stimulating Factor; D011493:Protein Kinase C; D010739:Phospholipase D; D013755:Tetradecanoylphorbol Acetate