6533b7dbfe1ef96bd12700e1
RESEARCH PRODUCT
Activation of NF-kappaB and IL-8 by yersinia enterocolitica invasin protein is conferred by engagement of rac1 and MAP kinase cascades.
Erwin BohnMartin AepfelbacherMichael KrachtChristoph Von Eichel-streiberElke HoffmannIngo B. AutenriethAgnès WiedemannGuntram A. Grasslsubject
rac1 GTP-Binding ProteinMAP Kinase Kinase 4MAP Kinase Signaling SystemRNA Stability[SDV]Life Sciences [q-bio]ImmunologyMitogen-activated protein kinase kinasep38 Mitogen-Activated Protein KinasesMicrobiologyBacterial AdhesionMAP2K703 medical and health sciencesBacterial ProteinsVirologyHumansASK1RNA Messengerc-RafAdhesins Bacterialcdc42 GTP-Binding ProteinrhoB GTP-Binding ProteinYersinia enterocolitica030304 developmental biologyMitogen-Activated Protein Kinase Kinases0303 health sciencesbiologyMAP kinase kinase kinase030306 microbiologyInterleukin-8Cyclin-dependent kinase 2JNK Mitogen-Activated Protein KinasesNF-kappa BProtein kinase RMolecular biologyCell biologybiology.proteinCyclin-dependent kinase 9Mitogen-Activated Protein KinasesrhoA GTP-Binding ProteinHeLa CellsSignal Transductiondescription
International audience; Yersinia enterocolitica triggers activation of the nuclear factor (NF)-kappaB and production of the proinflammatory chemokine interleukin (IL)-8 in intestinal epithelial cells. This activation is due to adhesion of the bacteria via their outer membrane protein invasin to the host cells. Using Clostridium difficile toxins that specifically inactivate small GTPases, and transfection of inhibitory proteins of the Rho-GTPases, we demonstrate that Rac1, but not Cdc42 or Rho, is required for activation of NF-kappaB by invasin. Invasin activated the mitogen activated protein kinases (MAPK) p38 and c-Jun N-terminal protein kinase (JNK) but not extracellular signal regulated kinase (ERK). The functional relevance of these pathways for invasin-mediated IL-8 expression was assessed by protein kinase inhibitors and dominant-negative kinase mutants. While NF-kappaB and JNK contribute to IL-8 transcription, p38 MAPK also acts through stabilization of IL-8 mRNA, as confirmed by quantitative RT-PCR and electrophoretic mobility shift assays. Transfection experiments with I-kappaB kinase (IKK)1 and IKK2 mutants indicate that the release of NF-kappaB from its cytoplasmic inhibitor I-kappaB and its translocation into the nucleus is mediated by these kinases. Our data identify Rac1 as a key intermediate in invasin-triggered IL-8 synthesis and demonstrate that maximum IL-8 induction involves several MAP kinase cascades.
year | journal | country | edition | language |
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2003-01-01 |