title: Effects of Elevated Atmospheric CO2 on Primary Metabolite Levels in Arabidopsis thaliana Col-0 Leaves: An Examination of Metabolome Data.
abstract: Elevated atmospheric CO(2) concentrations ([CO(2)]) affect primary metabolite levels because CO(2) is a direct substrate for photosynthesis. In several studies, the responses of primary metabolite levels have been examined using Arabidopsis thaliana leaves, but these results have not been comprehensively discussed. Here, we examined metabolome data for A. thaliana accession Col-0 leaves that were grown at elevated [CO(2)] with sufficient nitrogen (N) nutrition. At elevated [CO(2)], starch, monosaccharides and several major amino acids accumulated in leaves. The degree of accumulation depended on whether the rooting medium contained NH(4) (+) or only NO(3) (-). Because low N conditions induce an increase in carbohydrates similar to that of elevated [CO(2)], we compared the responses of primary metabolite levels between elevated [CO(2)] and low N conditions. Levels of the tricarboxylic acid (TCA) cycle-associated organic acids and major amino acids decreased with low N, but not with elevated [CO(2)]. Even at elevated [CO(2)], the low N induced the decreases in the levels of organic acids and major amino acids. A small sink size also affects the primary metabolite response patterns in leaves under elevated [CO(2)] conditions. Thus, care is necessary when interpreting primary metabolite changes in leaves of field-grown plants.
authors.affiliation: Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7 3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan knoguchi@bs.s.u-tokyo.ac.jp.
authors.forename: Ko
authors.initials: K
authors.lastname: Noguchi
authors.affiliation: Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7 3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Chihiro K
authors.initials: CK
authors.lastname: Watanabe
authors.affiliation: Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7 3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Terashima
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D050260:Carbohydrate Metabolism; D002245:Carbon Dioxide / Q000378:metabolism*; D019069:Cell Respiration; D002952:Citric Acid Cycle; D006019:Glycolysis; D055432:Metabolomics; D009584:Nitrogen / Q000378:metabolism; D010788:Photosynthesis; D018515:Plant Leaves / Q000378:metabolism*
chemical_list: D002245:Carbon Dioxide; D009584:Nitrogen
keywords: Arabidopsis thaliana; Elevated [CO2]; Low nitrogen condition; Primary metabolites