Differential requirements for ERK1/2 and P38 MAPK activation by thrombin in T cells. Role of P59Fyn and PKCepsilon.
Activation of the mitogen-activated protein kinase (MAPK) cascade is a well documented mechanism for the G-protein-coupled receptors. Here, we have analysed the requirements for ERKs and p38 MAPK activation by thrombin in Jurkat T cells. We show that thrombin-mediated ERKs activation requires both PTK and PKC activities, whereas p38 MAPK activation is dependent only on PTKs. Thrombin-induced ERK and p38 MAPK activation was more pronounced in p56Lck deficient cells indicating that this PTK exerts a negative control on MAPK activity. Accordingly, overexpression of p50 Csk a kinase that inactivates p56Lck induced constitutive activation of ERKs. Requirement for a Src kinase was evidenced by expression of a constitutively active form of p59Fyn in Jurkat cells. Besides its effect on tyrosine phosphorylation events, thrombin also triggered a rapid and robust redistribution of PKCepsilon and delta from the cytosol to the membrane. Expression of constitutively active and dominant negative PKCepsilon demonstrates the pivotal role of this PKC isoform in ERKs activation by thrombin. These data are consistent with a model where thrombin induces ERK activation via both PKC-dependent and independent pathways, whereas p38 MAPK activation requires only PTKs. The PKC-independent pathway requires Src kinases other than p56Lck more likely p59Fyn, while the PKC-dependent mechanism depends on PKCepsilon
Maulon
L
L
INSERM U526, 28 Avenue de Valombrose 06107 Nice Cedex 2, France.
Mari
B
B
Bertolotto
C
C
Ricci
J E
JE
Luciano
F
F
Belhacene
N
N
Deckert
M
M
Baier
G
G
Auberger
P
P
D016227:Benzoquinones; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism / Q000502:physiology*; D019169:Jurkat Cells; D047029:Lactams, Macrocyclic; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology*; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism* / Q000502:physiology; D011493:Protein Kinase C / Q000378:metabolism / Q000502:physiology*; D051745:Protein Kinase C-delta; D051744:Protein Kinase C-epsilon; D011505:Protein-Tyrosine Kinases / Q000378:metabolism / Q000502:physiology; D011518:Proto-Oncogene Proteins / Q000378:metabolism / Q000502:physiology*; D051076:Proto-Oncogene Proteins c-fyn; D016392:Proto-Oncogene Proteins pp60(c-src); D011809:Quinones / Q000494:pharmacology; D018179:Receptors, Thrombin / Q000502:physiology; D017828:Rifabutin / Q000031:analogs & derivatives; D013601:T-Lymphocytes / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D013917:Thrombin / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases
D016227:Benzoquinones; D004791:Enzyme Inhibitors; D007527:Isoenzymes; D047029:Lactams, Macrocyclic; D011518:Proto-Oncogene Proteins; D011809:Quinones; D018179:Receptors, Thrombin; D017828:Rifabutin; C020754:herbimycin; D011505:Protein-Tyrosine Kinases; C494957:FYN protein, human; C085377:MATK protein, human; D051076:Proto-Oncogene Proteins c-fyn; D016392:Proto-Oncogene Proteins pp60(c-src); C497258:PRKCD protein, human; C497255:PRKCE protein, human; D011493:Protein Kinase C; D051745:Protein Kinase C-delta; D051744:Protein Kinase C-epsilon; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D013917:Thrombin