title: Oxygen Sensing via the Ethylene Response Transcription Factor RAP2.12 Affects Plant Metabolism and Performance under Both Normoxia and Hypoxia.
abstract: Subgroup-VII-ethylene-response-factor (ERF-VII) transcription factors are involved in the regulation of hypoxic gene expression and regulated by proteasome-mediated proteolysis via the oxygen-dependent branch of the N-end-rule pathway. While research into ERF-VII mainly focused on their role to regulate anoxic gene expression, little is known on the impact of this oxygen-sensing system in regulating plant metabolism and growth. By comparing Arabidopsis (Arabidopsis thaliana) plants overexpressing N-end-rule-sensitive and insensitive forms of the ERF-VII-factor RAP2.12, we provide evidence that oxygen-dependent RAP2.12 stability regulates central metabolic processes to sustain growth, development, and anoxic resistance of plants. (1) Under normoxia, overexpression of N-end-rule-insensitive Δ13RAP2.12 led to increased activities of fermentative enzymes and increased accumulation of fermentation products, which were accompanied by decreased adenylate energy states and starch levels, and impaired plant growth and development, indicating a role of oxygen-regulated RAP2.12 degradation to prevent aerobic fermentation. (2) In Δ13RAP2.12-overexpressing plants, decreased carbohydrate reserves also led to a decrease in anoxic resistance, which was prevented by external Suc supply. (3) Overexpression of Δ13RAP2.12 led to decreased respiration rates, changes in the levels of tricarboxylic acid cycle intermediates, and accumulation of a large number of amino acids, including Ala and γ-amino butyric acid, indicating a role of oxygen-regulated RAP2.12 abundance in controlling the flux-modus of the tricarboxylic acid cycle. (4) The increase in amino acids was accompanied by increased levels of immune-regulatory metabolites. These results show that oxygen-sensing, mediating RAP2.12 degradation is indispensable to optimize metabolic performance, plant growth, and development under both normoxic and hypoxic conditions.
authors.affiliation: Ludwig-Maximilians-Universität München, Department Biologie I, 82152 Martinsried, Germany (M.V.P., S.I., C.A., M.L., P.G.); andInstitute of Biology I, RWTH Aachen University, 52074 Aachen, Germany (J.T.v.D.).
authors.forename: Melanie Verena
authors.initials: MV
authors.lastname: Paul
authors.affiliation: Ludwig-Maximilians-Universität München, Department Biologie I, 82152 Martinsried, Germany (M.V.P., S.I., C.A., M.L., P.G.); andInstitute of Biology I, RWTH Aachen University, 52074 Aachen, Germany (J.T.v.D.).
authors.forename: Srignanakshi
authors.initials: S
authors.lastname: Iyer
authors.affiliation: Ludwig-Maximilians-Universität München, Department Biologie I, 82152 Martinsried, Germany (M.V.P., S.I., C.A., M.L., P.G.); andInstitute of Biology I, RWTH Aachen University, 52074 Aachen, Germany (J.T.v.D.).
authors.forename: Carmen
authors.identifier: 0000-0002-8789-1103
authors.initials: C
authors.lastname: Amerhauser
authors.affiliation: Ludwig-Maximilians-Universität München, Department Biologie I, 82152 Martinsried, Germany (M.V.P., S.I., C.A., M.L., P.G.); andInstitute of Biology I, RWTH Aachen University, 52074 Aachen, Germany (J.T.v.D.).
authors.forename: Martin
authors.initials: M
authors.lastname: Lehmann
authors.affiliation: Ludwig-Maximilians-Universität München, Department Biologie I, 82152 Martinsried, Germany (M.V.P., S.I., C.A., M.L., P.G.); andInstitute of Biology I, RWTH Aachen University, 52074 Aachen, Germany (J.T.v.D.).
authors.forename: Joost T
authors.identifier: 0000-0001-7944-9289
authors.initials: JT
authors.lastname: van Dongen
authors.affiliation: Ludwig-Maximilians-Universität München, Department Biologie I, 82152 Martinsried, Germany (M.V.P., S.I., C.A., M.L., P.G.); andInstitute of Biology I, RWTH Aachen University, 52074 Aachen, Germany (J.T.v.D.) geigenberger@bio.lmu.de.
authors.forename: Peter
authors.identifier: 0000-0001-9512-349X
authors.initials: P
authors.lastname: Geigenberger
mesh_terms: D000332:Aerobiosis; D000596:Amino Acids / Q000378:metabolism; D000693:Anaerobiosis; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018533:Biomass; D002952:Citric Acid Cycle; D004268:DNA-Binding Proteins; D005030:Ethylenes / Q000378:metabolism; D005285:Fermentation; D008401:Gas Chromatography-Mass Spectrometry; D018506:Gene Expression Regulation, Plant; D055442:Metabolome; D055432:Metabolomics / Q000379:methods*; D009154:Mutation; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013395:Sucrose / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; D005030:Ethylenes; C569242:RAP2.12 protein, Arabidopsis; D014157:Transcription Factors; D013395:Sucrose; C036216:ethylene; D010100:Oxygen