title: The glutathione peroxidase gene family of Lotus japonicus: characterization of genomic clones, expression analyses and immunolocalization in legumes.
abstract: Despite the multiple roles played by antioxidants in rhizobia-legume symbioses, little is known about glutathione peroxidases (GPXs) in legumes. Here the characterization of six GPX genes of Lotus japonicus is reported. Expression of GPX genes was analysed by quantitative reverse transcription-polymerase chain reaction in L. japonicus and Lotus corniculatus plants exposed to various treatments known to generate reactive oxygen and/or nitrogen species. LjGPX1 and LjGPX3 were the most abundantly expressed genes in leaves, roots and nodules. Compared with roots, LjGPX1 and LjGPX6 were highly expressed in leaves and LjGPX3 and LjGPX6 in nodules. In roots, salinity decreased GPX4 expression, aluminium decreased expression of the six genes, and cadmium caused up-regulation of GPX3, GPX4 and GPX5 after 1 h and down-regulation of GPX1, GPX2, GPX4 and GPX6 after 3-24 h. Exposure of roots to sodium nitroprusside (a nitric oxide donor) for 1 h increased the mRNA levels of GPX4 and GPX6 by 3.3- and 30-fold, respectively. Thereafter, the GPX6 mRNA level remained consistently higher than that of the control. Immunogold labelling revealed the presence of GPX proteins in root and nodule amyloplasts and in leaf chloroplasts of L. japonicus and other legumes. Labelling was associated with starch grains. These results underscore the differential regulation of GPX expression in response to cadmium, aluminium and nitric oxide, and strongly support a role for GPX6 and possibly other GPX genes in stress and/or metabolic signalling.
authors.affiliation: Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apdo 13034, 50080 Zaragoza, Spain;College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;UMR 1136 Tree-Microbes Interactions, IFR110, Nancy University, Vandoeuvre-les-Nancy, France;Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Javier
authors.initials: J
authors.lastname: Ramos
authors.affiliation: Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apdo 13034, 50080 Zaragoza, Spain;College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;UMR 1136 Tree-Microbes Interactions, IFR110, Nancy University, Vandoeuvre-les-Nancy, France;Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Matamoros
authors.affiliation: Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apdo 13034, 50080 Zaragoza, Spain;College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;UMR 1136 Tree-Microbes Interactions, IFR110, Nancy University, Vandoeuvre-les-Nancy, France;Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Loreto
authors.initials: L
authors.lastname: Naya
authors.affiliation: Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apdo 13034, 50080 Zaragoza, Spain;College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;UMR 1136 Tree-Microbes Interactions, IFR110, Nancy University, Vandoeuvre-les-Nancy, France;Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Euan K
authors.initials: EK
authors.lastname: James
authors.affiliation: Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apdo 13034, 50080 Zaragoza, Spain;College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;UMR 1136 Tree-Microbes Interactions, IFR110, Nancy University, Vandoeuvre-les-Nancy, France;Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Rouhier
authors.affiliation: Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apdo 13034, 50080 Zaragoza, Spain;College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;UMR 1136 Tree-Microbes Interactions, IFR110, Nancy University, Vandoeuvre-les-Nancy, France;Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Shusei
authors.initials: S
authors.lastname: Sato
authors.affiliation: Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apdo 13034, 50080 Zaragoza, Spain;College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;UMR 1136 Tree-Microbes Interactions, IFR110, Nancy University, Vandoeuvre-les-Nancy, France;Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
authors.affiliation: Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apdo 13034, 50080 Zaragoza, Spain;College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;UMR 1136 Tree-Microbes Interactions, IFR110, Nancy University, Vandoeuvre-les-Nancy, France;Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Manuel
authors.initials: M
authors.lastname: Becana
mesh_terms: D000220:Adaptation, Biological / Q000235:genetics; D000595:Amino Acid Sequence; D007887:Fabaceae; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005979:Glutathione Peroxidase / Q000235:genetics* / Q000378:metabolism; D015151:Immunoblotting; D000070116:Lotus / Q000201:enzymology* / Q000648:ultrastructure; D008969:Molecular Sequence Data; D005810:Multigene Family; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D005979:Glutathione Peroxidase