title: Involvement of the ABCG37 transporter in secretion of scopoletin and derivatives by Arabidopsis roots in response to iron deficiency.
abstract: Studies of Iron (Fe) uptake mechanisms by plant roots have focussed on Fe(III)-siderophores or Fe(II) transport systems. Iron deficency also enhances root secretion of flavins and phenolics. However, the nature of these compounds, their transport outside the roots and their role in Fe nutrition are largely unknown. We used HPLC/ESI-MS (TOF) and HPLC/ESI-MS/MS (ion trap) to characterize fluorescent phenolic-type compounds accumulated in roots or exported to the culture medium of Arabidopsis plants in response to Fe deficiency. Wild-type and mutant plants altered either in phenylpropanoid biosynthesis or in the ABCG37 (PDR9) ABC transporter were grown under standard or Fe-deficient nutrition conditions and compared. Fe deficiency upregulates the expression of genes encoding enzymes of the phenylpropanoid pathway and leads to the synthesis and secretion of phenolic compounds belonging to the coumarin family. The ABCG37 gene is also upregulated in response to Fe deficiency and coumarin export is impaired in pdr9 mutant plants. Therefore it can be concluded that: Fe deficiency induces the secretion of coumarin compounds by Arabidopsis roots; the ABCG37 ABC transporter is required for this secretion to take place; and these compounds improved plant Fe nutrition.
authors.affiliation: Biochimie et Physiologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Montpellier 2, SupAgro. Bat 7, 2 place Viala, 34060, Montpellier Cedex 1, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Fourcroy
authors.affiliation: Department of Plant Nutrition, Estación Experimental de Aula Dei (CSIC), Av. Montañana 1005, E-50080, Zaragoza, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: Sisó-Terraza
authors.affiliation: Biochimie et Physiologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Montpellier 2, SupAgro. Bat 7, 2 place Viala, 34060, Montpellier Cedex 1, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Sudre
authors.affiliation: New Organic Materials Unit, Institute of Materials Science of Aragón, CSIC-University of Zaragoza, c/Pedro Cerbuna 12, E-50009, Zaragoza, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Savirón
authors.affiliation: Biochimie et Physiologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Montpellier 2, SupAgro. Bat 7, 2 place Viala, 34060, Montpellier Cedex 1, France.
authors.forename: Guilhem
authors.initials: G
authors.lastname: Reyt
authors.affiliation: Biochimie et Physiologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Montpellier 2, SupAgro. Bat 7, 2 place Viala, 34060, Montpellier Cedex 1, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Gaymard
authors.affiliation: Department of Plant Nutrition, Estación Experimental de Aula Dei (CSIC), Av. Montañana 1005, E-50080, Zaragoza, Spain.
authors.forename: Anunciación
authors.initials: A
authors.lastname: Abadía
authors.affiliation: Department of Plant Nutrition, Estación Experimental de Aula Dei (CSIC), Av. Montañana 1005, E-50080, Zaragoza, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Abadia
authors.affiliation: Department of Plant Nutrition, Estación Experimental de Aula Dei (CSIC), Av. Montañana 1005, E-50080, Zaragoza, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Álvarez-Fernández
authors.affiliation: Biochimie et Physiologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Montpellier 2, SupAgro. Bat 7, 2 place Viala, 34060, Montpellier Cedex 1, France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Briat
mesh_terms: D000070996:ATP Binding Cassette Transporter, Subfamily G; D018528:ATP-Binding Cassette Transporters / Q000235:genetics* / Q000378:metabolism; D000222:Adaptation, Physiological / Q000235:genetics*; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001692:Biological Transport; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D000090463:Iron Deficiencies; D053858:Metabolic Networks and Pathways; D009154:Mutation; D018517:Plant Roots / Q000378:metabolism*; D012603:Scopoletin / Q000378:metabolism*; D013312:Stress, Physiological / Q000235:genetics; D053719:Tandem Mass Spectrometry; D015854:Up-Regulation
chemical_list: D000070996:ATP Binding Cassette Transporter, Subfamily G; D018528:ATP-Binding Cassette Transporters; D029681:Arabidopsis Proteins; C515019:PDR9 protein, Arabidopsis; D012603:Scopoletin
keywords: ABC transporter; coumarins; iron (Fe) nutrition; phenolic compounds; root secretion