title: Cytokinin Determines Thiol-Mediated Arsenic Tolerance and Accumulation.
abstract: The presence of arsenic in soil and water is a constant threat to plant growth in many regions of the world. Phytohormones act in the integration of growth control and stress response, but their role in plant responses to arsenic remains to be elucidated. Here, we show that arsenate [As(V)], the most prevalent arsenic chemical species in nature, causes severe depletion of endogenous cytokinins (CKs) in the model plant Arabidopsis (Arabidopsis thaliana). We found that CK signaling mutants and transgenic plants with reduced endogenous CK levels showed an As(V)-tolerant phenotype. Our data indicate that in CK-depleted plants exposed to As(V), transcript levels of As(V)/phosphate-transporters were similar or even higher than in wild-type plants. In contrast, CK depletion provoked the coordinated activation of As(V) tolerance mechanisms, leading to the accumulation of thiol compounds such as phytochelatins and glutathione, which are essential for arsenic sequestration. Transgenic CK-deficient Arabidopsis and tobacco lines show a marked increase in arsenic accumulation. Our findings indicate that CK is an important regulatory factor in plant adaptation to arsenic stress.
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Thotegowdanapalya C
authors.identifier: 0000-0001-8425-251X
authors.initials: TC
authors.lastname: Mohan
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Gabriel
authors.initials: G
authors.lastname: Castrillo
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Cristina
authors.initials: C
authors.lastname: Navarro
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Sonia
authors.initials: S
authors.lastname: Zarco-Fernández
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Eswarayya
authors.identifier: 0000-0002-5666-8865
authors.initials: E
authors.lastname: Ramireddy
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Cristian
authors.initials: C
authors.lastname: Mateo
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Angel M
authors.identifier: 0000-0003-1966-0239
authors.initials: AM
authors.lastname: Zamarreño
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Javier
authors.initials: J
authors.lastname: Paz-Ares
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Riansares
authors.initials: R
authors.lastname: Muñoz
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Jose M
authors.identifier: 0000-0001-6352-9612
authors.initials: JM
authors.lastname: García-Mina
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Luis E
authors.identifier: 0000-0003-3492-5813
authors.initials: LE
authors.lastname: Hernández
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.).
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmülling
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (T.C.M., G.C., C.N., C.M., J.P.-A., A.L.); Department of Analytical Chemistry, School of Chemical Sciences, Universidad Complutense de Madrid, Madrid, Spain (S.Z.-F., R.M.); Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany (E.R., T.S.); Department of Environmental Biology (Agricultural Chemistry and Biology Group), Faculty of Sciences, University of Navarra, Sciencies Building, 31008 Pamplona, Spain (A.M.Z., J.M.G.-M.); and Departamento de Biología, Universidad Autónoma de Madrid, Edif. de Biológicas BS13, Campus de Cantoblanco, 28049 Madrid, Spain (L.E.H.) aleyva@cnb.csic.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Leyva
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects*; D001151:Arsenic / Q000378:metabolism* / Q000633:toxicity*; D019328:Buthionine Sulfoximine / Q000494:pharmacology; D003583:Cytokinins / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D008658:Inactivation, Metabolic / Q000187:drug effects; D010641:Phenotype; D054811:Phytochelatins / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D003583:Cytokinins; D013438:Sulfhydryl Compounds; D019328:Buthionine Sulfoximine; D054811:Phytochelatins; D005978:Glutathione; D001151:Arsenic