title: Heterologous expression of the yeast arsenite efflux system ACR3 improves Arabidopsis thaliana tolerance to arsenic stress.
abstract: • Arsenic contamination has a negative impact on crop cultivation and on human health. As yet, no proteins have been identified in plants that mediate the extrusion of arsenic. Here, we heterologously expressed the yeast (Saccharomyces cerevisiae) arsenite efflux transporter ACR3 into Arabidopsis to evaluate how this affects plant tolerance and tissue arsenic contents. • ACR3 was cloned from yeast and transformed into wild-type and nip7;1 Arabidopsis. Arsenic tolerance was determined at the cellular level using vitality stains in protoplasts, in intact seedlings grown on agar plates and in mature plants grown hydroponically. Arsenic efflux was measured from protoplasts and from intact plants, and arsenic levels were measured in roots and shoots of plants exposed to arsenate. • At the cellular level, all transgenic lines showed increased tolerance to arsenite and arsenate and a greater capacity for arsenate efflux. With intact plants, three of four stably transformed lines showed improved growth, whereas only transgenic lines in the wild-type background showed increased efflux of arsenite into the external medium. The presence of ACR3 hardly affected tissue arsenic levels, but increased arsenic translocation to the shoot. • Heterologous expression of yeast ACR3 endows plants with greater arsenic resistance, but does not lower significantly arsenic tissue levels.
authors.affiliation: Biology Department, Area 9, University of York, York YO10 5DD, UK.
authors.forename: Waqar
authors.initials: W
authors.lastname: Ali
authors.affiliation: Biology Department, Area 9, University of York, York YO10 5DD, UK.
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Isner
authors.affiliation: Department of Genomics and Molecular Biotechnology, Institute of Food Biotechnology and Genomics, Osipovskogo str. 2a, Kiev-123, 04123, Ukraine.
authors.forename: Stanislav V
authors.initials: SV
authors.lastname: Isayenkov
authors.affiliation: Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
authors.forename: Wenju
authors.initials: W
authors.lastname: Liu
authors.affiliation: Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
authors.forename: Fang-Jie
authors.initials: FJ
authors.lastname: Zhao
authors.affiliation: Biology Department, Area 9, University of York, York YO10 5DD, UK.
authors.forename: Frans J M
authors.initials: FJM
authors.lastname: Maathuis
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D001149:Arsenates / Q000378:metabolism; D001151:Arsenic / Q000032:analysis / Q000378:metabolism*; D018053:Arsenites / Q000378:metabolism; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism; D018527:Hydroponics; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D030821:Plants, Genetically Modified; D011523:Protoplasts; D011993:Recombinant Fusion Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism; D036226:Seedlings / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D013312:Stress, Physiological / Q000235:genetics*; D014170:Transformation, Genetic; D019076:Transgenes
chemical_list: C109281:ACR3 protein, S cerevisiae; D001149:Arsenates; D018053:Arsenites; D026901:Membrane Transport Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; C015001:arsenite; D001151:Arsenic; C025657:arsenic acid