The p38/RK mitogen-activated protein kinase pathway regulates interleukin-6 synthesis response to tumor necrosis factor.
Tumour necrosis factor (TNF) is a pleiotropic cytokine, the activities of which include effects on gene expression, cell growth and cell death. The biological signalling mechanisms which are responsible for these TNF effects remain largely unknown. Here we demonstrate that the stress-responsive p38 mitogen-activated protein (MAP) kinase is involved in TNF-induced cytokine expression. TNF Treatment of cell activated the p38 MAP kinase pathway, as revealed by increased phosphorylation of p38 MAP kinase itself, activation of the substrate protein MAPKAP kinase-2, and culminating in the phosphorylation of the heat shock protein 27 (hsp27). Pretreatment of cells with the highly specific p38 MAP kinase inhibitor SB203580 completely blocked this TNF-induced activation of MAPKAP kinase-2 and hsp27 phosphorylation. Under the same conditions, SB203580 also completely inhibited TNF-induced synthesis of interleukin (IL)-6 and expression of a reporter gene that was driven by a minimal promoter containing two NF-Kappa B elements. However, neither TNF-induced DNA binding of TNF-Kappa B nor TNF-induced phosphorylation of its subunits was modulated by SB203580, suggesting that NF-Kappa B is not a direct target for the p38 MAP kinase pathway. Interestingly, TNF-induced cytotoxicity was not affected by SB203580, indicating that p38 MAP kinase might be an interesting target to interfere selectively with TNF-induced gene activation.
Beyaert
R
R
Laboratory of Molecular Biology, University of Ghent, Belgium.
Cuenda
A
A
Vanden Berghe
W
W
Plaisance
S
S
Lee
J C
JC
Haegeman
G
G
Cohen
P
P
Fiers
W
W
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002460:Cell Line; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis; D006367:HeLa Cells; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000235:genetics; D047908:Intracellular Signaling Peptides and Proteins; D051379:Mice; D020928:Mitogen-Activated Protein Kinases; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000378:metabolism; D009842:Oligopeptides / Q000235:genetics; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases; D000099190:MAP-Kinase-Activated Kinase 2
D017871:Calcium-Calmodulin-Dependent Protein Kinases; D004791:Enzyme Inhibitors; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D007093:Imidazoles; D015850:Interleukin-6; D047908:Intracellular Signaling Peptides and Proteins; D020928:Mitogen-Activated Protein Kinases; D016328:NF-kappa B; D009842:Oligopeptides; D017346:Protein Serine-Threonine Kinases; D011725:Pyridines; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D048051:p38 Mitogen-Activated Protein Kinases; D000099190:MAP-Kinase-Activated Kinase 2; C093642:SB 203580