Activation of p38 mitogen-activated protein kinase by formyl-methionyl-leucyl-phenylalanine in rat neutrophils.
The signaling pathways leading to p38 mitogen-activated protein kinase (MAPK) activation in formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated rat neutrophils were examined. Immunoblot analysis with antibodies against a phosphorylated form of p38 MAPK showed that fMLP-stimulated p38 MAPK activation was dependent on a pertussis toxin-sensitive G protein. Two phosphatidylinositol 3-kinase inhibitors, wortmannin and 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002), did not affect the p38 MAPK activation. Phosphorylation of p38 MAPK was concentration dependently attenuated by a tyrosine kinase inhibitor, genistein, and by a Ca(2+)-dependent protein kinase C inhibitor, 13-cyanoethyl-12-methyl-6,7,12,13-tetrahydroindolo[2,3-a]pyrrolo[3 , 4-c]carbazole-7-one (Gö6976). However, the protein kinase C inhibitors with a broader spectrum, 2-[1-(3-dimethylaminopropyl)-5-methoxy-1H-indol-3-yl]-3-(1H-indol-3-y l)-maleimide (Gö6983) and 2-[1-(3-dimethylaminopropyl)-1H-indol-3-yl]-3-(1H-indol-3-yl)-maleimi de (GF109203X), had no inhibitory effect. fMLP-stimulated p38 MAPK phosphorylation was also reduced in cells pretreated with a phospholipase C inhibitor, 1-[6-((17beta-3-methoxyestra-1,3, 5(10)-trien-17-yl)amino)hexyl]-1H-pyrrole-2,5-dione (U73122), or preloaded with an intracellular Ca(2+) chelator, 1, 2-bis-(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA). We conclude that phosphorylation of p38 MAPK by fMLP stimulation in rat neutrophils is dependent on G(i/o) protein, nonreceptor tyrosine kinase, phospholipase C/Ca(2+), and probably Ca(2+)-dependent protein kinase C pathways.
Chang
L C
LC
Department of Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan.
Wang
J P
JP
D000818:Animals; D002118:Calcium / Q000378:metabolism; D054729:Calcium-Calmodulin-Dependent Protein Kinase Type 1; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D002614:Chelating Agents / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D020536:Enzyme Activators / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000378:metabolism; D015151:Immunoblotting; D020928:Mitogen-Activated Protein Kinases; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology*; D009504:Neutrophils / Q000187:drug effects / Q000201:enzymology*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D051381:Rats; D010738:Type C Phospholipases / Q000037:antagonists & inhibitors; D048051:p38 Mitogen-Activated Protein Kinases
D002118:Calcium; D054729:Calcium-Calmodulin-Dependent Protein Kinase Type 1; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D002614:Chelating Agents; D020536:Enzyme Activators; D004791:Enzyme Inhibitors; D019204:GTP-Binding Proteins; D020928:Mitogen-Activated Protein Kinases; D009240:N-Formylmethionine Leucyl-Phenylalanine; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D011505:Protein-Tyrosine Kinases; D010738:Type C Phospholipases; D048051:p38 Mitogen-Activated Protein Kinases; C517599:Camk1 protein, rat; C517682:Pnck protein, rat