title: The mitochondrial glutathione peroxidase GPX3 is essential for H2O2 homeostasis and root and shoot development in rice.
abstract: Glutathione (GSH) peroxidases (GPXs: EC 1.11.1.9 and EC1.11.1.12) are non-heme thiol peroxidases that catalyze the reduction of H2O2 or organic hydroperoxides to water, and they have been identified in almost all kingdoms of life. The rice glutathione peroxidase (OsGPX) gene family is comprised of 5 members spread throughout a range of sub cellular compartments. The OsGPX gene family is induced in response to exogenous H2O2 and cold stress. In contrast, they are down regulated in response to drought and UV-B light treatments. Transgenic rice plants have been generated that lack mitochondrial OsGPX3. These GPX3s plants showed shorter roots and shoots compared to non-transformed (NT) plants, and higher amounts of H2O2 mitochondrial release were observed in the roots of these plants cultivated under normal conditions. This accumulation of H2O2 is positively associated with shorter root length in GPX3s plants compared to NT ones. Moreover, GPX3 promoter analysis indicated that it is mainly expressed in root tissue. These results suggest that silencing the mitochondrial OsGPX3 gene impairs normal plant development and leads to a stress-induced morphogenic response via H2O2 accumulation.
authors.affiliation: Department of Genetics, Federal University of Rio Grande do Sul, RS, Brazil.
authors.forename: Gisele
authors.initials: G
authors.lastname: Passaia
authors.forename: Leila Spagnolo
authors.initials: LS
authors.lastname: Fonini
authors.forename: Andréia
authors.initials: A
authors.lastname: Caverzan
authors.forename: Douglas
authors.initials: D
authors.lastname: Jardim-Messeder
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Christoff
authors.forename: Marcos Letaif
authors.initials: ML
authors.lastname: Gaeta
authors.forename: Jorge Ernesto
authors.initials: JE
authors.lastname: de Araujo Mariath
authors.forename: Rogério
authors.initials: R
authors.lastname: Margis
authors.forename: Marcia
authors.initials: M
authors.lastname: Margis-Pinheiro
mesh_terms: D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D055785:Gene Knockdown Techniques; D020868:Gene Silencing / Q000187:drug effects; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006706:Homeostasis / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000378:metabolism* / Q000494:pharmacology; D008928:Mitochondria / Q000187:drug effects / Q000201:enzymology*; D012275:Oryza / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development*; D018520:Plant Shoots / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development*; D011401:Promoter Regions, Genetic / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D010940:Plant Proteins; D006861:Hydrogen Peroxide; D005979:Glutathione Peroxidase