title: The basic leucine zipper transcription factor ABSCISIC ACID RESPONSE ELEMENT-BINDING FACTOR2 is an important transcriptional regulator of abscisic acid-dependent grape berry ripening processes.
abstract: In grape (Vitis vinifera), abscisic acid (ABA) accumulates during fruit ripening and is thought to play a pivotal role in this process, but the molecular basis of this control is poorly understood. This work characterizes ABSCISIC ACID RESPONSE ELEMENT-BINDING FACTOR2 (VvABF2), a grape basic leucine zipper transcription factor belonging to a phylogenetic subgroup previously shown to be involved in ABA and abiotic stress signaling in other plant species. VvABF2 transcripts mainly accumulated in the berry, from the onset of ripening to the harvesting stage, and were up-regulated by ABA. Microarray analysis of transgenic grape cells overexpressing VvABF2 showed that this transcription factor up-regulates and/or modifies existing networks related to ABA responses. In addition, grape cells overexpressing VvABF2 exhibited enhanced responses to ABA treatment compared with control cells. Among the VvABF2-mediated responses highlighted in this study, the synthesis of phenolic compounds and cell wall softening were the most strongly affected. VvABF2 overexpression strongly increased the accumulation of stilbenes that play a role in plant defense and human health (resveratrol and piceid). In addition, the firmness of fruits from tomato (Solanum lycopersicum) plants overexpressing VvABF2 was strongly reduced. These data indicate that VvABF2 is an important transcriptional regulator of ABA-dependent grape berry ripening.
authors.affiliation: Université de Bordeaux, Institut National de la Recherce Agronomique, Institut des Sciences de la Vigne et du Vin, Ecophysiologie et Génomique Fonctionnelle de la Vigne, UMR 1287, F-33140 Villenave d'Ornon, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Nicolas
authors.forename: David
authors.initials: D
authors.lastname: Lecourieux
authors.forename: Christian
authors.initials: C
authors.lastname: Kappel
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Cluzet
authors.forename: Grant
authors.initials: G
authors.lastname: Cramer
authors.forename: Serge
authors.initials: S
authors.lastname: Delrot
authors.forename: Fatma
authors.initials: F
authors.lastname: Lecourieux
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism* / Q000494:pharmacology; D000595:Amino Acid Sequence; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism; D005638:Fruit / Q000254:growth & development / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D018551:Solanum lycopersicum / Q000187:drug effects / Q000235:genetics; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D013267:Stilbenes / Q000378:metabolism; D027843:Vitis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*
chemical_list: D050976:Basic-Leucine Zipper Transcription Factors; D010940:Plant Proteins; D013267:Stilbenes; D000040:Abscisic Acid