title: 2,4-D and IAA Amino Acid Conjugates Show Distinct Metabolism in Arabidopsis.
abstract: The herbicide 2,4-D exhibits an auxinic activity and therefore can be used as a synthetic and traceable analog to study auxin-related responses. Here we identified that not only exogenous 2,4-D but also its amide-linked metabolite 2,4-D-Glu displayed an inhibitory effect on plant growth via the TIR1/AFB auxin-mediated signaling pathway. To further investigate 2,4-D metabolite conversion, identity and activity, we have developed a novel purification procedure based on the combination of ion exchange and immuno-specific sorbents combined with a sensitive liquid chromatography-mass spectrometry method. In 2,4-D treated samples, 2,4-D-Glu and 2,4-D-Asp were detected at 100-fold lower concentrations compared to 2,4-D levels, showing that 2,4-D can be metabolized in the plant. Moreover, 2,4-D-Asp and 2,4-D-Glu were identified as reversible forms of 2,4-D homeostasis that can be converted to free 2,4-D. This work paves the way to new studies of auxin action in plant development.
authors.affiliation: Department of Virology, Veterinary Research Institute, Brno, Czech Republic.
authors.forename: Luděk
authors.initials: L
authors.lastname: Eyer
authors.affiliation: Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, Umeå, Sweden.
authors.forename: Thomas
authors.initials: T
authors.lastname: Vain
authors.affiliation: Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany CAS & Faculty of Science of Palacký University, Olomouc, Czech Republic.
authors.forename: Barbora
authors.initials: B
authors.lastname: Pařízková
authors.affiliation: Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany CAS & Faculty of Science of Palacký University, Olomouc, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Oklestkova
authors.affiliation: Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria.
authors.forename: Elke
authors.initials: E
authors.lastname: Barbez
authors.affiliation: Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University, Olomouc, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Kozubíková
authors.affiliation: Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University, Olomouc, Czech Republic.
authors.forename: Tomáš
authors.initials: T
authors.lastname: Pospíšil
authors.affiliation: Department of Virology, Veterinary Research Institute, Brno, Czech Republic.
authors.forename: Roksana
authors.initials: R
authors.lastname: Wierzbicka
authors.affiliation: Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Kleine-Vehn
authors.affiliation: Department of Virology, Veterinary Research Institute, Brno, Czech Republic.
authors.forename: Milan
authors.initials: M
authors.lastname: Fránek
authors.affiliation: Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany CAS & Faculty of Science of Palacký University, Olomouc, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Strnad
authors.affiliation: Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, Umeå, Sweden.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Robert
authors.affiliation: Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany CAS & Faculty of Science of Palacký University, Olomouc, Czech Republic.
authors.forename: Ondrej
authors.identifier: http://orcid.org/0000-0003-3452-0154
authors.initials: O
authors.lastname: Novak
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D044783:F-Box Proteins / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D006540:Herbicides / Q000494:pharmacology; D006706:Homeostasis; D007210:Indoleacetic Acids / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000494:pharmacology; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D029681:Arabidopsis Proteins; D044783:F-Box Proteins; D006540:Herbicides; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D011956:Receptors, Cell Surface; C501405:TIR1 protein, Arabidopsis; D015084:2,4-Dichlorophenoxyacetic Acid