title: c-Jun NH(2)-terminal kinase (JNK)1 and JNK2 have distinct roles in CD8(+) T cell activation.
abstract: The c-Jun NH(2)-terminal kinase (JNK) signaling pathway is induced by cytokines and stress stimuli and is implicated in cell death and differentiation, but the specific function of this pathway depends on the cell type. Here we examined the role of JNK1 and JNK2 in CD8(+) T cells. Unlike CD4(+) T cells, the absence of JNK2 causes increased interleukin (IL)-2 production and proliferation of CD8(+) T cells. In contrast, JNK1-deficient CD8(+) T cells are unable to undergo antigen-stimulated expansion in vitro, even in the presence of exogenous IL-2. The hypoproliferation of these cells is associated with impaired IL-2 receptor alpha chain (CD25) gene and cell surface expression. The reduced level of nuclear activating protein 1 (AP-1) complexes in activated JNK1-deficient CD8(+) T cells can account for the impaired IL-2 receptor alpha chain gene expression. Thus, JNK1 and JNK2 play different roles during CD8(+) T cell activation and these roles differ from those in CD4(+) T cells.
authors.affiliation: Section of Immunobiology, Department of Medicine, University of Vermont, Burlington, VT 05405, USA.
authors.forename: Dietrich
authors.initials: D
authors.lastname: Conze
authors.forename: Troy
authors.initials: T
authors.lastname: Krahl
authors.forename: Norman
authors.initials: N
authors.lastname: Kennedy
authors.forename: Linda
authors.initials: L
authors.lastname: Weiss
authors.forename: Joanne
authors.initials: J
authors.lastname: Lumsden
authors.forename: Patricia
authors.initials: P
authors.lastname: Hess
authors.forename: Richard A
authors.initials: RA
authors.lastname: Flavell
authors.forename: Graham
authors.initials: G
authors.lastname: Le Gros
authors.forename: Roger J
authors.initials: RJ
authors.lastname: Davis
authors.forename: Mercedes
authors.initials: M
authors.lastname: Rincón
mesh_terms: D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D009980:Influenza A virus / Q000276:immunology; D007376:Interleukin-2 / Q000494:pharmacology; D053645:Interleukin-2 Receptor alpha Subunit; D008198:Lymph Nodes / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology*; D051379:Mice; D018345:Mice, Knockout; D048055:Mitogen-Activated Protein Kinase 8; D048056:Mitogen-Activated Protein Kinase 9; D020928:Mitogen-Activated Protein Kinases / Q000172:deficiency / Q000235:genetics / Q000276:immunology*; D009976:Orthomyxoviridae Infections / Q000276:immunology; D018123:Receptors, Interleukin / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013997:Time Factors
chemical_list: C508018:Il2ra protein, mouse; D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; D018123:Receptors, Interleukin; D048056:Mitogen-Activated Protein Kinase 9; D048055:Mitogen-Activated Protein Kinase 8; D020928:Mitogen-Activated Protein Kinases