title: Mediation of TNF receptor-associated factor effector functions by apoptosis signal-regulating kinase-1 (ASK1).
abstract: Tumor necrosis factor-alpha (TNF), a major inflammatory cytokine, generates a wide variety of cellular responses via key cytoplasmic adaptor molecules named TNF receptor-associated factors (TRAFs). We report that TRAF2, TRAF5 and TRAF6 associate with apoptosis signal-regulating kinase 1 (ASK1), and a catalytically-inactive ASK1 mutant blocks stress-activated protein kinase (SAPK)/Jun NH2-terminal kinase (JNK) activation by these TRAFs. A truncated derivative of TRAF2, which inhibits SAPK activation by TNF, blocks TNF-induced ASK1 activation. Furthermore, protection from TNF-induced cell death conferred by an ASK1 mutant is dependent upon TRAF2. Hence, ASK1 is a common mediator of TRAF-regulated SAPK and apoptosis signaling, and the TRAF2 - ASK1 connection completes the signaling cascade from TNF to SAPK/JNK activation.
authors.affiliation: Department of Medical Biophysics, Ontario Cancer Institute, 610 University Avenue, Toronto, Ontario M5G 2M9, Canada.
authors.forename: K P
authors.initials: KP
authors.lastname: Hoeflich
authors.forename: W C
authors.initials: WC
authors.lastname: Yeh
authors.forename: Z
authors.initials: Z
authors.lastname: Yao
authors.forename: T W
authors.initials: TW
authors.lastname: Mak
authors.forename: J R
authors.initials: JR
authors.lastname: Woodgett
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D019556:COS Cells; D002478:Cells, Cultured; D004789:Enzyme Activation; D048031:JNK Mitogen-Activated Protein Kinases; D048848:MAP Kinase Kinase Kinase 5; D020930:MAP Kinase Kinase Kinases / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010449:Peptide Mapping; D011506:Proteins / Q000378:metabolism*; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D047992:TNF Receptor-Associated Factor 2; D048015:TNF Receptor-Associated Factor 5; D048029:TNF Receptor-Associated Factor 6; D014409:Tumor Necrosis Factor-alpha
chemical_list: D011506:Proteins; D018124:Receptors, Tumor Necrosis Factor; D047992:TNF Receptor-Associated Factor 2; D048015:TNF Receptor-Associated Factor 5; D048029:TNF Receptor-Associated Factor 6; D014409:Tumor Necrosis Factor-alpha; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048848:MAP Kinase Kinase Kinase 5; D020930:MAP Kinase Kinase Kinases; C482859:Map3k5 protein, mouse