title: Over-expression of the bacterial phytase US417 in Arabidopsis reduces the concentration of phytic acid and reveals its involvement in the regulation of sulfate and phosphate homeostasis and signaling.
abstract: Phytic acid (PA) is the main phosphorus storage form in plant seeds. It is recognized as an anti-nutrient for humans and non-ruminant animals, as well as one of the major sources of phosphorus that contributes to eutrophication. Therefore, engineering plants with low PA content without affecting plant growth capacity has become a major focus in plant breeding. Nevertheless, lack of knowledge on the role of PA seed reserves in regulating plant growth and in maintaining ion homeostasis hinders such an agronomical application. In this context, we report here that the over-expression of the bacterial phytase PHY-US417 in Arabidopsis leads to a significant decrease in seed PA, without any effect on the seed germination potential. Interestingly, this over-expression also induced a higher remobilization of free iron during germination. Moreover, the PHY-over-expressor lines show an increase in inorganic phosphate and sulfate contents, and a higher biomass production after phosphate starvation. Finally, phosphate sensing was altered because of the changes in the expression of genes induced by phosphate starvation or involved in phosphate or sulfate transport. Together, these results show that the over-expression of PHY-US417 reduces PA concentration, and provide the first evidence for the involvement of PA in the regulation of sulfate and phosphate homeostasis and signaling.
authors.affiliation: Laboratoire de Protection et Amélioration des Plantes, Centre de Biotechnologie de Sfax, BP "1177" 3018, Sfax, Tunisie Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Université Montpellier 2, Montpellier SupAgro, Biochimie et Physiologie Moléculaire des Plantes, Bat 7, 2place Viala, 34060 Montpellier cedex 2, France.
authors.forename: Nibras
authors.initials: N
authors.lastname: Belgaroui
authors.affiliation: Laboratoire de Protection et Amélioration des Plantes, Centre de Biotechnologie de Sfax, BP "1177" 3018, Sfax, Tunisie.
authors.forename: Ikram
authors.initials: I
authors.lastname: Zaidi
authors.affiliation: Laboratoire de Microorganismes et de Biomolécules, Centre de Biotechnologie de Sfax, BP "1177" 3018, Sfax, Tunisie.
authors.forename: Ameny
authors.initials: A
authors.lastname: Farhat
authors.affiliation: Laboratoire de Microorganismes et de Biomolécules, Centre de Biotechnologie de Sfax, BP "1177" 3018, Sfax, Tunisie.
authors.forename: Hichem
authors.initials: H
authors.lastname: Chouayekh
authors.affiliation: Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Université Montpellier 2, Montpellier SupAgro, Biochimie et Physiologie Moléculaire des Plantes, Bat 7, 2place Viala, 34060 Montpellier cedex 2, France.
authors.forename: Nadia
authors.initials: N
authors.lastname: Bouain
authors.affiliation: Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Université Montpellier 2, Montpellier SupAgro, Biochimie et Physiologie Moléculaire des Plantes, Bat 7, 2place Viala, 34060 Montpellier cedex 2, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Chay
authors.affiliation: Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Université Montpellier 2, Montpellier SupAgro, Biochimie et Physiologie Moléculaire des Plantes, Bat 7, 2place Viala, 34060 Montpellier cedex 2, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Curie
authors.affiliation: Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Université Montpellier 2, Montpellier SupAgro, Biochimie et Physiologie Moléculaire des Plantes, Bat 7, 2place Viala, 34060 Montpellier cedex 2, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Mari
authors.affiliation: Laboratoire de Protection et Amélioration des Plantes, Centre de Biotechnologie de Sfax, BP "1177" 3018, Sfax, Tunisie Current address: International Center for Biosaline Agriculture (ICBA), PO Box 14660, Dubai, UAE.
authors.forename: Khaled
authors.initials: K
authors.lastname: Masmoudi
authors.affiliation: Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Université Montpellier 2, Montpellier SupAgro, Biochimie et Physiologie Moléculaire des Plantes, Bat 7, 2place Viala, 34060 Montpellier cedex 2, France.
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Davidian
authors.affiliation: Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Université Montpellier 2, Montpellier SupAgro, Biochimie et Physiologie Moléculaire des Plantes, Bat 7, 2place Viala, 34060 Montpellier cedex 2, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Berthomieu
authors.affiliation: Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Université Montpellier 2, Montpellier SupAgro, Biochimie et Physiologie Moléculaire des Plantes, Bat 7, 2place Viala, 34060 Montpellier cedex 2, France moez.hanin@cbs.rnrt.tn hatem.rouached@supagro.inra.fr.
authors.forename: Hatem
authors.initials: H
authors.lastname: Rouached
authors.affiliation: Laboratoire de Protection et Amélioration des Plantes, Centre de Biotechnologie de Sfax, BP "1177" 3018, Sfax, Tunisie Université de Sfax, Institut Supérieur de Biotechnologie, BP "1175" 3038 Sfax, Tunisie moez.hanin@cbs.rnrt.tn hatem.rouached@supagro.inra.fr.
authors.forename: Moez
authors.initials: M
authors.lastname: Hanin
mesh_terms: D010832:6-Phytase / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D006706:Homeostasis; D007501:Iron / Q000378:metabolism; D028061:Phosphate Transport Proteins / Q000235:genetics / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism*; D010833:Phytic Acid / Q000378:metabolism*; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D036226:Seedlings / Q000235:genetics / Q000254:growth & development; D012639:Seeds / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013431:Sulfates / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; C520845:PHT1;1 protein, Arabidopsis; C494975:PT2 protein, Arabidopsis; D028061:Phosphate Transport Proteins; D010710:Phosphates; D013431:Sulfates; D010833:Phytic Acid; D007501:Iron; D010832:6-Phytase
keywords: Homeostasis; Phosphorus; Phytase; Phytic acid; Signaling; Sulfate