title: Oligo-carrageenan kappa-induced reducing redox status and activation of TRR/TRX system increase the level of indole-3-acetic acid, gibberellin A3 and trans-zeatin in Eucalyptus globulus trees.
abstract: Eucalyptus globulus trees treated with oligo-carrageenan (OC) kappa showed an increase in NADPH, ascorbate and glutathione levels and activation of the thioredoxin reductase (TRR)/thioredoxin (TRX) system which enhance photosynthesis, basal metabolism and growth. In order to analyze whether the reducing redox status and the activation of thioredoxin reductase (TRR)/thioredoxin (TRX) increased the level of growth-promoting hormones, trees were treated with water (control), with OC kappa, or with inhibitors of ascorbate synthesis, lycorine, glutathione synthesis, buthionine sulfoximine (BSO), NADPH synthesis, CHS-828, and thioredoxin reductase activity, auranofine, and with OC kappa, and cultivated for four additional months. Eucalyptus trees treated with OC kappa showed an increase in the levels of the auxin indole 3-acetic acid (IAA), gibberellin A3 (GA3) and the cytokinin trans-zeatin (t-Z) as well as a decrease in the level of the brassinosteroid epi-brassinolide (EB). In addition, treatment with lycorine, BSO, CHS-828 and auranofine inhibited the increase in IAA, GA3 and t-Z as well as the decrease in EB levels. Thus, the reducing redox status and the activation of TRR/TRX system induced by OC kappa increased the levels of IAA, GA3 and t-Z levels determining, at least in part, the stimulation of growth in Eucalyptus trees.
authors.affiliation: Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, 9170022 Santiago, Chile. alberto.ngf@gmail.com.
authors.forename: Alberto
authors.initials: A
authors.lastname: González
authors.affiliation: Plant Physiology and Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, 9170022 Santiago, Chile. rodrigo.contrerasar@usach.cl.
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Contreras
authors.affiliation: Plant Physiology and Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, 9170022 Santiago, Chile. gustavo.zuniga@usach.cl.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Zúiga
authors.affiliation: Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, 9170022 Santiago, Chile. alejandra.moenne@usach.cl.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Moenne
mesh_terms: D002351:Carrageenan / Q000737:chemistry / Q000494:pharmacology*; D005052:Eucalyptus / Q000187:drug effects / Q000254:growth & development*; D005875:Gibberellins / Q000096:biosynthesis; D005978:Glutathione / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism*; D009249:NADP / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D013880:Thioredoxin-Disulfide Reductase / Q000378:metabolism*; D013879:Thioredoxins / Q000378:metabolism*; D015026:Zeatin / Q000096:biosynthesis
chemical_list: D005875:Gibberellins; D007210:Indoleacetic Acids; D013879:Thioredoxins; D009249:NADP; C030737:indoleacetic acid; D015026:Zeatin; D002351:Carrageenan; C007842:gibberellic acid; D013880:Thioredoxin-Disulfide Reductase; D005978:Glutathione