Response to metal stress of Nicotiana langsdorffii plants wild-type and transgenic for the rat glucocorticoid receptor gene

• DOI: 10.1016/j.jplph.2012.12.009
• Publication Date: 2013-02-08T15:45:45Z
• Authors: Roger Fuoco; Patrizia Bogani; Gabriele Capodaglio; Massimo Del Bubba; Ornella Abollino; Stefania Giannarelli; Maria Michela Spi...; Beatrice Muscatello; Saer Doumett; Clara Turetta; Roberta Zangrando; Vincenzo Zelano; Marcello Buiatti
• Keywords: Chromium; Nicotiana; 0106 biological sciences; Shikimic Acid; 01 natural sciences; Receptors, Glucocorticoid; Plant Growth Regulators; Gene Expression Regulation, Plant; Stress, Physiological; Metals, Heavy; Nicotiana; transgenic plants; metal stress; Animals; Metabolomics; Glucocorticoids; Indoleacetic Acids; Polyphenols; Plants, Genetically Modified; Transgenic N. langsdorffii, Metal stress, Phytohormones, Metabolomics; Rats; 3. Good health; Plant Leaves; Transgenic N. langsdorffii; Metal stress; Phytohormones; Metabolomics; Chlorogenic Acid; Salicylic Acid; Abscisic Acid; Cadmium

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.