title: Arabidopsis wat1 (walls are thin1)-mediated resistance to the bacterial vascular pathogen, Ralstonia solanacearum, is accompanied by cross-regulation of salicylic acid and tryptophan metabolism.
abstract: Inactivation of Arabidopsis WAT1 (Walls Are Thin1), a gene required for secondary cell-wall deposition, conferred broad-spectrum resistance to vascular pathogens, including the bacteria Ralstonia solanacearum and Xanthomonas campestris pv. campestris, and the fungi Verticillium dahliae and Verticillium albo-atrum. Introduction of NahG, the bacterial salicylic acid (SA)-degrading salicylate hydroxylase gene, into the wat1 mutant restored full susceptibility to both R. solanacearum and X. campestris pv. campestris. Moreover, SA content was constitutively higher in wat1 roots, further supporting a role for SA in wat1-mediated resistance to vascular pathogens. By combining transcriptomic and metabolomic data, we demonstrated a general repression of indole metabolism in wat1-1 roots as shown by constitutive down-regulation of several genes encoding proteins of the indole glucosinolate biosynthetic pathway and reduced amounts of tryptophan (Trp), indole-3-acetic acid and neoglucobrassicin, the major form of indole glucosinolate in roots. Furthermore, the susceptibility of the wat1 mutant to R. solanacearum was partially restored when crossed with either the trp5 mutant, an over-accumulator of Trp, or Pro35S:AFB1-myc, in which indole-3-acetic acid signaling is constitutively activated. Our original hypothesis placed cell-wall modifications at the heart of the wat1 resistance phenotype. However, the results presented here suggest a mechanism involving root-localized metabolic channeling away from indole metabolites to SA as a central feature of wat1 resistance to R. solanacearum.
authors.affiliation: Université de Toulouse, UPS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.|Centre National de la Recherche Scientifique, CNRS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Denancé
authors.affiliation: Université de Toulouse, UPS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.|Centre National de la Recherche Scientifique, CNRS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Ranocha
authors.affiliation: Institut National de la Recherche Agronomique, INRA, AgroParisTech, Unité Mixte de Recherche 1318, Institut Jean-Pierre Bourgin, Centre de Versailles-Grignon, Route de Saint-Cyr, F-78026, Versailles, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Oria
authors.affiliation: Institut National de la Recherche Agronomique, INRA, Unité Mixte de Recherche 441, Laboratoire des Interactions Plantes Microorganismes, 24 Chemin de Borde Rouge, F-31326, Castanet-Tolosan, France.|Centre National de la Recherche Scientifique, CNRS, Unité Mixte de Recherche 2594, Laboratoire des Interactions Plantes Microorganismes, 24 Chemin de Borde Rouge, F-31326, Castanet-Tolosan, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Barlet
authors.affiliation: Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Campus Montegancedo, E-28223, Pozuelo de Alarcón, Spain.
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Rivière
authors.affiliation: Laboratory of Phytopathology, Wageningen University, Droevendaalsesteeg 1, 6708, PB Wageningen, The Netherlands.
authors.forename: Koste A
authors.initials: KA
authors.lastname: Yadeta
authors.affiliation: Université de Toulouse, UPS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.|Centre National de la Recherche Scientifique, CNRS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Hoffmann
authors.affiliation: Institut National de la Recherche Agronomique, INRA, AgroParisTech, Unité Mixte de Recherche 1318, Institut Jean-Pierre Bourgin, Centre de Versailles-Grignon, Route de Saint-Cyr, F-78026, Versailles, France.
authors.forename: François
authors.initials: F
authors.lastname: Perreau
authors.affiliation: Institut National de la Recherche Agronomique, INRA, AgroParisTech, Unité Mixte de Recherche 1318, Institut Jean-Pierre Bourgin, Centre de Versailles-Grignon, Route de Saint-Cyr, F-78026, Versailles, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Clément
authors.affiliation: Institut National de la Recherche Agronomique, INRA, AgroParisTech, Unité Mixte de Recherche 1318, Institut Jean-Pierre Bourgin, Centre de Versailles-Grignon, Route de Saint-Cyr, F-78026, Versailles, France.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Maia-Grondard
authors.affiliation: Laboratory of Phytopathology, Wageningen University, Droevendaalsesteeg 1, 6708, PB Wageningen, The Netherlands.
authors.forename: Grardy C M
authors.initials: GC
authors.lastname: van den Berg
authors.affiliation: Université de Toulouse, UPS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.|Centre National de la Recherche Scientifique, CNRS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Savelli
authors.affiliation: Université de Toulouse, UPS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.|Centre National de la Recherche Scientifique, CNRS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Fournier
authors.affiliation: Université de Toulouse, UPS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.|Centre National de la Recherche Scientifique, CNRS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.
authors.forename: Yann
authors.initials: Y
authors.lastname: Aubert
authors.affiliation: Unité de Recherche en Génomique Végétale, Institut National de la Recherche Agronomique (INRA)/ Centre National de la Recherche Scientifique (CNRS), 91057, Evry, France.
authors.forename: Sandra
authors.initials: S
authors.lastname: Pelletier
authors.affiliation: Laboratory of Phytopathology, Wageningen University, Droevendaalsesteeg 1, 6708, PB Wageningen, The Netherlands.
authors.forename: Bart P H J
authors.initials: BP
authors.lastname: Thomma
authors.affiliation: Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Campus Montegancedo, E-28223, Pozuelo de Alarcón, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Molina
authors.affiliation: Institut National de la Recherche Agronomique, INRA, AgroParisTech, Unité Mixte de Recherche 1318, Institut Jean-Pierre Bourgin, Centre de Versailles-Grignon, Route de Saint-Cyr, F-78026, Versailles, France.
authors.forename: Lise
authors.initials: L
authors.lastname: Jouanin
authors.affiliation: Institut National de la Recherche Agronomique, INRA, Unité Mixte de Recherche 441, Laboratoire des Interactions Plantes Microorganismes, 24 Chemin de Borde Rouge, F-31326, Castanet-Tolosan, France.|Centre National de la Recherche Scientifique, CNRS, Unité Mixte de Recherche 2594, Laboratoire des Interactions Plantes Microorganismes, 24 Chemin de Borde Rouge, F-31326, Castanet-Tolosan, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Marco
authors.affiliation: Université de Toulouse, UPS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.|Centre National de la Recherche Scientifique, CNRS, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, BP 42617, F-31326, Castanet-Tolosan, France.
authors.forename: Deborah
authors.initials: D
authors.lastname: Goffner
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000382:microbiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D005658:Fungi / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000276:immunology; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D010935:Plant Diseases / Q000276:immunology / Q000382:microbiology; D018517:Plant Roots; D044224:Pseudomonas syringae; D043368:Ralstonia solanacearum; D020156:Salicylic Acid / Q000378:metabolism*; D013997:Time Factors; D014364:Tryptophan / Q000378:metabolism*; D016959:Xanthomonas campestris
chemical_list: D029681:Arabidopsis Proteins; D026901:Membrane Transport Proteins; C560559:Wat1 protein, Arabidopsis; D014364:Tryptophan; D020156:Salicylic Acid