title: Maturation of nematode-induced galls in Medicago truncatula is related to water status and primary metabolism modifications.
abstract: Root-knot nematodes are obligatory plant parasitic worms that establish and maintain an intimate relationship with their host plants. During a compatible interaction, these nematodes induce the redifferentiation of root cells into multinucleate and hypertrophied giant cells (GCs). These metabolically active feeding cells constitute the exclusive source of nutrients for the nematode. We analyzed the modifications of water status, ionic content and accumulation of metabolites in development and mature galls induced by Meloidogyne incognita and in uninfected roots of Medicago truncatula plants. Water potential and osmotic pressure are significantly modified in mature galls compared to developing galls and control roots. Ionic content is significantly modified in galls compared to roots. Principal component analyses of metabolite content showed that mature gall metabolism is significantly modified compared to developing gall metabolism. The most striking differences were the three-fold increase of trehalose content associated to the five-fold diminution in glucose concentration in mature galls. Gene expression analysis showed that trehalose accumulation was, at least, partially linked to a significantly lower expression of the trehalase gene in mature galls. Our results point to significant modifications of gall physiology during maturation.
authors.affiliation: Université de Nice Sophia-Antipolis, UMR Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; INRA UMR 7254 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; CNRS UMR1355 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France. Electronic address: fbaldacc@ulb.ac.be.
authors.forename: Fabien
authors.initials: F
authors.lastname: Baldacci-Cresp
authors.affiliation: Université de Bordeaux 2, UMR 1332 Biologie du Fruit et Pathologie, Centre INRA de Bordeaux, F-33140 Villenave d'Ornon, France; Metabolome Facility of Bordeaux Functional Genomics Center, IBVM, Centre INRA de Bordeaux, F-33140 Villenave d'Ornon, France.
authors.forename: Mickaël
authors.initials: M
authors.lastname: Maucourt
authors.affiliation: Metabolome Facility of Bordeaux Functional Genomics Center, IBVM, Centre INRA de Bordeaux, F-33140 Villenave d'Ornon, France; INRA, UMR 1332 Biologie du Fruit et Pathologie, Centre INRA de Bordeaux, F-33140 Villenave d'Ornon, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Deborde
authors.affiliation: Université de Nice Sophia-Antipolis, UMR Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; INRA UMR 7254 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; CNRS UMR1355 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Pierre
authors.affiliation: Metabolome Facility of Bordeaux Functional Genomics Center, IBVM, Centre INRA de Bordeaux, F-33140 Villenave d'Ornon, France; INRA, UMR 1332 Biologie du Fruit et Pathologie, Centre INRA de Bordeaux, F-33140 Villenave d'Ornon, France.
authors.forename: Annick
authors.initials: A
authors.lastname: Moing
authors.affiliation: Université de Nice Sophia-Antipolis, UMR Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; INRA UMR 7254 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; CNRS UMR1355 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France.
authors.forename: Renaud
authors.initials: R
authors.lastname: Brouquisse
authors.affiliation: Université de Nice Sophia-Antipolis, UMR Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; INRA UMR 7254 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; CNRS UMR1355 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Favery
authors.affiliation: Université de Nice Sophia-Antipolis, UMR Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; INRA UMR 7254 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France; CNRS UMR1355 Institut Sophia Agrobiotech, 400 route des chappes BP167, F-06903 Sophia Antipolis, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Frendo
mesh_terms: D000818:Animals; D054884:Host-Pathogen Interactions; D046913:Medicago truncatula / Q000378:metabolism / Q000469:parasitology* / Q000502:physiology; D019906:Nuclear Magnetic Resonance, Biomolecular; D009997:Osmotic Pressure; D018517:Plant Roots / Q000469:parasitology; D025341:Principal Component Analysis; D014431:Tylenchoidea / Q000502:physiology*
keywords: Giant cell; Inorganic ions; Medicago truncatula; Metabolites; Root-knot nematode; Water status