Distinct UV-B and UV-A/blue light signal transduction pathways induce chalcone synthase gene expression in Arabidopsis cells

• Published in: The Plant cell 1996-09, Vol.8 (9), p.1555-1567
• Main Authors: Christie, John M., Jenkins, Gareth I.
• Format: Article
• Language: English
• Subjects: Acyltransferases - genetics; amonio fenilalanina liasa; antimetabolite; antimetabolites; antimetabolitos; Arabidopsis - enzymology; Arabidopsis - genetics; Arabidopsis - radiation effects; Arabidopsis thaliana; arn mensajero; arn messager; B lymphocytes; calcio; Calcium; Calcium - metabolism; calmodulin; Calmodulin - metabolism; calmodulina; calmoduline; cation; cationes; cations; cell culture; Cell culture techniques; cicloheximida; citoplasma; Complementary DNA; cultivo de celulas; culture de cellule; cycloheximide; Cycloheximide - pharmacology; cytoplasm; cytoplasme; enzyme inhibitors; Enzyme Inhibitors - pharmacology; esterasas; esterase; esterases; expresion genica; expression des genes; gene; Gene expression; Gene expression regulation; Gene Expression Regulation, Enzymologic - drug effects; Gene Expression Regulation, Enzymologic - radiation effects; Gene Expression Regulation, Plant - drug effects; Gene Expression Regulation, Plant - radiation effects; genes; Genes, Plant - radiation effects; genetica; genetics; genetique; inhibidores de enzimas; inhibiteur d' enzyme; Light; lumiere; luz; messenger rna; phenylalanine ammonia lyase; Phenylalanine Ammonia-Lyase - genetics; Phosphoprotein Phosphatases - antagonists & inhibitors; Phosphorylation; Plant cells; Plant Proteins - metabolism; Plants; protein kinase; Protein Kinase Inhibitors; protein synthesis; Protein Synthesis Inhibitors - pharmacology; proteina quinasa; proteine kinase; radiacion ultravioleta; rayonnement ultraviolet; RNA; Signal transduction; Signal Transduction - radiation effects; sintesis de proteinas; synthese proteique; transferasas; transferase; transferases; ultraviolet radiation; Ultraviolet Rays
• ISSN: 1040-4651; 1532-298X
• DOI: 10.1105/tpc.8.9.1555

UV and blue light control the expression of flavonoid biosynthesis genes in a range of higher plants. To investigate the signal transduction processes involved in the induction of chalcone synthase (CHS) gene expression by UV-B and UV-A/blue light, we examined the, effects of specific agonists and inhibitors of known signaling components in mammalian systems in a photomixotrophic Arabidopsis cell suspension culture. CHS expression is induced specifically by these wavelengths in the cell culture, in a manner similar to that in mature Arabidopsis leaf tissue. Both the UV-B and UV-A/blue phototransduction processes involve calcium, although the elevation of cytosolic calcium is insufficient on its own to stimulate CHS expression. The UV-A/blue light induction of CHS expression does not appear to involve calmodulin, whereas the UV-B response does; this difference indicates that the signal transduction pathways are, at least in part, distinct. We provide evidence that both pathways involve reversible protein phosphorylation and require protein synthesis. The UV-B and UV-A/blue light signaling pathways are therefore different from the phytochrome signal transduction pathway regulating CHS expression in other species.