title: The transcription factor AREB1 regulates primary metabolic pathways in tomato fruits.
abstract: Tomato fruit development is regulated both by the action of plant hormones and by tight genetic control. Recent studies suggest that abscisic acid (ABA) signalling may affect different aspects of fruit maturation. Previously, it was shown that SlAREB1, an ABA-regulated transcription factor involved in stress-induced responses, is expressed in seeds and in fruit tissues in tomato. Here, the role of SlAREB1 in regulating the expression of genes relevant for primary metabolic pathways and affecting the metabolic profile of the fruit was investigated using transgenic tomato lines. Metabolite profiling using gas chromatography-time of flight mass spectrometry (GC-TOF-MS) and non-targeted liquid chromatography-mass spectrometry (LC-MS) was performed on pericarp tissue from fruits harvested at three stages of fruit development. Principal component analysis of the data could distinguish the metabolite profiles of non-transgenic fruits from those that overexpress and down-regulate SlAREB1. Overexpression of SlAREB1 resulted in increased content of organic acids, hexoses, hexose-phosphates, and amino acids in immature green, mature green, and red ripe fruits, and these modifications correlated with the up-regulation of enzyme-encoding genes involved in primary carbohydrate and amino acid metabolism. A non-targeted LC-MS analysis indicated that the composition of secondary metabolites is also affected in transgenic lines. In addition, gene expression data revealed that some genes associated with fruit ripening are also up-regulated in SlAREB1-overexpressing lines compared with wild-type and antisense lines. Taken together, the results suggest that SlAREB1 participates in the regulation of the metabolic programming that takes place during fruit ripening and that may explain part of the role of ABA in fruit development in tomato.
authors.affiliation: Instituto de Biología Vegetal y Biotecnología, Universidad de Talca, 2 Norte 685, Talca, Chile.
authors.forename: Adriana
authors.initials: A
authors.lastname: Bastías
authors.affiliation: Instituto de Biología Vegetal y Biotecnología, Universidad de Talca, 2 Norte 685, Talca, Chile.
authors.forename: Mónica
authors.initials: M
authors.lastname: Yañez
authors.affiliation: Max-Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, D-14476 Potsdam, Germany.
authors.forename: Sonia
authors.initials: S
authors.lastname: Osorio
authors.affiliation: Departament de Ciències Agràries i del Medi Natural, Universitat Jaume I, Campus Riu Sec, 12071 Castelló de la Plana, Spain.
authors.forename: Vicent
authors.initials: V
authors.lastname: Arbona
authors.affiliation: Departament de Ciències Agràries i del Medi Natural, Universitat Jaume I, Campus Riu Sec, 12071 Castelló de la Plana, Spain.
authors.forename: Aurelio
authors.initials: A
authors.lastname: Gómez-Cadenas
authors.affiliation: Max-Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, D-14476 Potsdam, Germany.
authors.forename: Alisdair R
authors.initials: AR
authors.lastname: Fernie
authors.affiliation: Instituto de Biología Vegetal y Biotecnología, Universidad de Talca, 2 Norte 685, Talca, Chile jcasaretto@utalca.cl jcasaret@uoguelph.ca.
authors.forename: José A
authors.initials: JA
authors.lastname: Casaretto
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D000596:Amino Acids / Q000378:metabolism; D005638:Fruit / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D006601:Hexoses / Q000378:metabolism; D018551:Solanum lycopersicum / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D053858:Metabolic Networks and Pathways; D010937:Plant Growth Regulators / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D006601:Hexoses; D010937:Plant Growth Regulators; D010940:Plant Proteins; D014157:Transcription Factors; D000040:Abscisic Acid
keywords: AREB; Abscisic acid; fruit development; fruit ripening; metabolism; tomato.