title: Root and shoot performance of Arabidopsis thaliana exposed to elevated CO2: A physiologic, metabolic and transcriptomic response.
abstract: The responsiveness of C3 plants to raised atmospheric [CO2] levels has been frequently described as constrained by photosynthetic downregulation. The main goal of the current study was to characterize the shoot-root relationship and its implications in plant responsiveness under elevated [CO2] conditions. For this purpose, Arabidopsis thaliana plants were exposed to elevated [CO2] (800ppm versus 400ppm [CO2]) and fertilized with a mixed (NH4NO3) nitrogen source. Plant growth, physiology, metabolite and transcriptomic characterizations were carried out at the root and shoot levels. Plant growth under elevated [CO2] conditions was doubled due to increased photosynthetic rates and gas exchange measurements revealed that these plants maintain higher photosynthetic rates over extended periods of time. This positive response of photosynthetic rates to elevated [CO2] was caused by the maintenance of leaf protein and Rubisco concentrations at control levels alongside enhanced energy efficiency. The increased levels of leaf carbohydrates, organic acids and amino acids supported the augmented respiration rates of plants under elevated [CO2]. A transcriptomic analysis allowed the identification of photoassimilate allocation and remobilization as fundamental process used by the plants to maintain the outstanding photosynthetic performance. Moreover, based on the relationship between plant carbon status and hormone functioning, the transcriptomic analyses provided an explanation of why phenology accelerates under elevated [CO2] conditions.
authors.affiliation: Dpto Ciencias del Medio Natural, Universidad Pública de Navarra, Campus de Arrosadía, E-31192 Mutilva Baja, Spain; Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus de Arrosadía, E-31192 Mutilva Baja, Spain. Electronic address: ivan.jauregui@unavarra.es.
authors.forename: Iván
authors.initials: I
authors.lastname: Jauregui
authors.affiliation: Dpto Ciencias del Medio Natural, Universidad Pública de Navarra, Campus de Arrosadía, E-31192 Mutilva Baja, Spain; Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus de Arrosadía, E-31192 Mutilva Baja, Spain.
authors.forename: Pedro M
authors.initials: PM
authors.lastname: Aparicio-Tejo
authors.affiliation: Biología Molecular y Bioquímica, Instituto Andaluz de Biología, Unidad Asociada UMA-CSIC, Universidad de Málaga, Campus Universitario de Teatinos, E-29071 Málaga, Spain.
authors.forename: Concepción
authors.initials: C
authors.lastname: Avila
authors.affiliation: Biología Molecular y Bioquímica, Instituto Andaluz de Biología, Unidad Asociada UMA-CSIC, Universidad de Málaga, Campus Universitario de Teatinos, E-29071 Málaga, Spain.
authors.forename: Marina
authors.initials: M
authors.lastname: Rueda-López
authors.affiliation: Instituto de Agrobiotecnología (IdAB), Universidad Pública de Navarra-CSIC-Gobierno de Navarra, Campus de Arrosadía, E-31192 Mutilva Baja, Spain; Dpto Biología Vegetal, Universidad del País Vasco, Barrio Sarriena, s/n, E-48940 Leioa, Vizkaia, Spain.
authors.forename: Iker
authors.initials: I
authors.lastname: Aranjuelo
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D018533:Biomass; D002244:Carbon / Q000378:metabolism; D002245:Carbon Dioxide / Q000494:pharmacology*; D018506:Gene Expression Regulation, Plant; D055442:Metabolome; D009584:Nitrogen / Q000494:pharmacology; D010788:Photosynthesis; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D018520:Plant Shoots / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D012273:Ribulose-Bisphosphate Carboxylase / Q000378:metabolism; D059467:Transcriptome
chemical_list: D010940:Plant Proteins; D002245:Carbon Dioxide; D002244:Carbon; D012273:Ribulose-Bisphosphate Carboxylase; D009584:Nitrogen
keywords: Arabidopsis; CO(2); Carbohydrate transport; Photosynthesis; Source-sink; Transcriptomic