title: Anisomycin selectively desensitizes signalling components involved in stress kinase activation and fos and jun induction.
abstract: Anisomycin, a translational inhibitor secreted by Streptomyces spp., strongly activates the stress-activated mitogen-activated protein (MAP) kinases JNK/SAPK (c-Jun NH2-terminal kinase/stress-activated protein kinase) and p38/RK in mammalian cells, resulting in rapid induction of immediate-early (IE) genes in the nucleus. Here, we have characterized this response further with respect to homologous and heterologous desensitization of IE gene induction and stress kinase activation. We show that anisomycin acts exactly like a signalling agonist in eliciting highly specific and virtually complete homologous desensitization. Anisomycin desensitization of a panel of IE genes (c-fos, fosB, c-jun, junB, and junD), using epidermal growth factor (EGF), basic fibroblast growth factor, (bFGF), tumor necrosis factor alpha (TNF-alpha), anisomycin, tetradecanoyl phorbol acetate (TPA), and UV radiation as secondary stimuli, was found to be extremely specific both with respect to the secondary stimuli and at the level of individual genes. Further, we show that anisomycin-induced homologous desensitization is caused by the fact that anisomycin no longer activates the JNK/SAPK and p38/RK MAP kinase cascades in desensitized cells. In anisomycin-desensitized cells, activation of JNK/SAPKs by UV radiation and hyperosmolarity is almost completely lost, and that of the p38/RK cascade is reduced to about 50% of the normal response. However, all other stimuli produced normal or augmented activation of these two kinase cascades in anisomycin-desensitized cells. These data show that anisomycin behaves like a true signalling agonist and suggest that the anisomycin-desensitized signalling component(s) is not involved in JNK/SAPK or p38/RK activation by EGF, bFGF, TNF-alpha, or TPA but may play a significant role in UV- and hyperosmolarity-stimulated responses.
authors.affiliation: Nuclear Signalling Laboratory, Developmental Biology Research Centre, The Randall Institute, King's College London, United Kingdom.
authors.forename: C A
authors.initials: CA
authors.lastname: Hazzalin
authors.forename: R
authors.initials: R
authors.lastname: Le Panse
authors.forename: E
authors.initials: E
authors.lastname: Cano
authors.forename: L C
authors.initials: LC
authors.lastname: Mahadevan
mesh_terms: D000818:Animals; D000841:Anisomycin / Q000494:pharmacology*; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002478:Cells, Cultured; D004789:Enzyme Activation; D004815:Epidermal Growth Factor / Q000494:pharmacology; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D048031:JNK Mitogen-Activated Protein Kinases; D051379:Mice; D008809:Mice, Inbred C3H; D020928:Mitogen-Activated Protein Kinases; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology*; D009994:Osmolar Concentration; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis*; D016755:Proto-Oncogene Proteins c-jun / Q000096:biosynthesis*; D015398:Signal Transduction / Q000187:drug effects*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D014466:Ultraviolet Rays; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D019384:Nucleic Acid Synthesis Inhibitors; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D014409:Tumor Necrosis Factor-alpha; D016222:Fibroblast Growth Factor 2; D004815:Epidermal Growth Factor; D000841:Anisomycin; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D013755:Tetradecanoylphorbol Acetate