title: Modulation of Zn/Cd P(1B2)-ATPase activities in Arabidopsis impacts differently on Zn and Cd contents in shoots and seeds.
abstract: Zn is an essential microelement for all living cells and Zn deficiency is widespread in world's population. At the same time, high Zn concentration and low Cd concentration are toxic to the environment. Both Zn and Cd are transported in planta via Zn/Cd HMA transporters. Engineering of HMAs expression in plants may provide a way for Zn biofortification of food as well as phytoremediation of polluted soils. In the present study we have assessed the impact of Zn/Cd HMAs invalidation/overexpression in Arabidopsis thaliana on Zn and Cd translocation from the roots to the shoots and in Zn grain filling. Overexpression of AtHMA4 had a large impact on Zn and Cd translocation and resulted in a 3-fold higher potential of Cd and Zn extraction from an industrial soil highly contaminated by Zn, Pb and Cd. Despite AtHMA4 overexpressing lines presenting a higher Zn concentration in the shoot, the Zn content in the seeds was found to be lower than in wild type plants. Our results indicate that AtHMA4 overexpression is an efficient tool to increase the root to shoot translocation of Zn and Cd in plants. Concerning biofortification of seeds, this study underlines the need for specific promoters to drive an expression pattern of the transporters in favour of Zn grain filling.
authors.affiliation: IBEB-SBVME Laboratoire de Biologie du Développement des Plantes, UMR7265 CNRS-Commissariat à l'Energie Atomique et aux Energies Alternatives Cadarache, Université Aix-Marseille, F-13108 Saint-Paul-lez-Durance, France. alain.vavasseur@cea.fr.
authors.forename: Pierre
authors.initials: P
authors.lastname: Cun
authors.forename: Catherine
authors.initials: C
authors.lastname: Sarrobert
authors.forename: Pierre
authors.initials: P
authors.lastname: Richaud
authors.forename: Anne
authors.initials: A
authors.lastname: Chevalier
authors.forename: Paul
authors.initials: P
authors.lastname: Soreau
authors.forename: Pascaline
authors.initials: P
authors.lastname: Auroy
authors.forename: Antoine
authors.initials: A
authors.lastname: Gravot
authors.forename: Anthony
authors.initials: A
authors.lastname: Baltz
authors.forename: Nathalie
authors.initials: N
authors.lastname: Leonhardt
authors.forename: Alain
authors.initials: A
authors.lastname: Vavasseur
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002104:Cadmium / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism; D012639:Seeds / Q000378:metabolism; D015032:Zinc / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D002104:Cadmium; D000251:Adenosine Triphosphatases; C477864:HMA4 protein, Arabidopsis; D015032:Zinc