title: Response to metal stress of Nicotiana langsdorffii plants wild-type and transgenic for the rat glucocorticoid receptor gene.
abstract: Recently our findings have shown that the integration of the gene coding for the rat gluco-corticoid receptor (GR receptor) in Nicotiana langsdorffii plants induced morphophysiological effects in transgenic plants through the modification of their hormonal pattern. Phytohormones play a key role in plant responses to many different biotic and abiotic stresses since a modified hormonal profile up-regulates the activation of secondary metabolites involved in the response to stress. In this work transgenic GR plants and isogenic wild type genotypes were exposed to metal stress by treating them with 30ppm cadmium(II) or 50ppm chromium(VI). Hormonal patterns along with changes in key response related metabolites were then monitored and compared. Heavy metal up-take was found to be lower in the GR plants. The transgenic plants exhibited higher values of S-abscisic acid (S-ABA) and 3-indole acetic acid (IAA), salicylic acid and total polyphenols, chlorogenic acid and antiradical activity, compared to the untransformed wild type plants. Both Cd and Cr treatments led to an increase in hormone concentrations and secondary metabolites only in wild type plants. Analysis of the results suggests that the stress responses due to changes in the plant's hormonal system may derive from the interaction between the GR receptor and phytosteroids, which are known to play a key role in plant physiology and development.
authors: Department of Chemistry and Industrial Chemistry, University of Pisa, Via Risorgimento 35, 56126 Pisa, Italy. fuoco@dcci.unipi.it
authors: Roger
authors: R
authors: Fuoco
authors: Patrizia
authors: P
authors: Bogani
authors: Gabriele
authors: G
authors: Capodaglio
authors: Massimo
authors: M
authors: Del Bubba
authors: Ornella
authors: O
authors: Abollino
authors: Stefania
authors: S
authors: Giannarelli
authors: Maria Michela
authors: MM
authors: Spiriti
authors: Beatrice
authors: B
authors: Muscatello
authors: Saer
authors: S
authors: Doumett
authors: Clara
authors: C
authors: Turetta
authors: Roberta
authors: R
authors: Zangrando
authors: Vincenzo
authors: V
authors: Zelano
authors: Marcello
authors: M
authors: Buiatti
mesh_terms: D000040:Abscisic Acid / Q000032:analysis / Q000378:metabolism; D000818:Animals; D002104:Cadmium / Q000378:metabolism / Q000494:pharmacology; D002726:Chlorogenic Acid / Q000032:analysis / Q000378:metabolism; D002857:Chromium / Q000378:metabolism / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D005938:Glucocorticoids / Q000494:pharmacology; D007210:Indoleacetic Acids / Q000032:analysis / Q000378:metabolism; D055432:Metabolomics; D019216:Metals, Heavy / Q000378:metabolism / Q000494:pharmacology*; D010937:Plant Growth Regulators / Q000032:analysis / Q000378:metabolism*; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D030821:Plants, Genetically Modified; D059808:Polyphenols / Q000032:analysis / Q000378:metabolism; D051381:Rats; D011965:Receptors, Glucocorticoid / Q000235:genetics*; D020156:Salicylic Acid / Q000032:analysis / Q000378:metabolism; D012765:Shikimic Acid / Q000032:analysis / Q000378:metabolism; D013312:Stress, Physiological; D014026:Nicotiana / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology*
chemical_list: D005938:Glucocorticoids; D007210:Indoleacetic Acids; D019216:Metals, Heavy; D010937:Plant Growth Regulators; D059808:Polyphenols; D011965:Receptors, Glucocorticoid; D002104:Cadmium; D002857:Chromium; D012765:Shikimic Acid; D002726:Chlorogenic Acid; C030737:indoleacetic acid; D000040:Abscisic Acid; D020156:Salicylic Acid