title: Characterization of the ABA-regulated global responses to dehydration in Arabidopsis by metabolomics.
abstract: Drought is the major environmental threat to agricultural production and distribution worldwide. Adaptation by plants to dehydration stress is a complex biological process that involves global changes in gene expression and metabolite composition. Here, using one type of functional genomics analysis, metabolomics, we characterized the metabolic phenotypes of Arabidopsis wild-type and a knockout mutant of the NCED3 gene (nc3-2) under dehydration stress. NCED3 plays a role in the dehydration-inducible biosynthesis of abscisic acid (ABA), a phytohormone that is important in the dehydration-stress response in higher plants. Metabolite profiling performed using two types of mass spectrometry (MS) systems, gas chromatography/time-of-flight MS (GC/TOF-MS) and capillary electrophoresis MS (CE-MS), revealed that accumulation of amino acids depended on ABA production, but the level of the oligosaccharide raffinose was regulated by ABA independently under dehydration stress. Metabolic network analysis showed that global metabolite-metabolite correlations occurred in dehydration-increased amino acids in wild-type, and strong correlations with raffinose were reconstructed in nc3-2. An integrated metabolome and transcriptome analysis revealed ABA-dependent transcriptional regulation of the biosynthesis of the branched-chain amino acids, saccharopine, proline and polyamine. This metabolomics analysis revealed new molecular mechanisms of dynamic metabolic networks in response to dehydration stress.
authors.affiliation: Gene Discovery Research Group, RIKEN Plant Science Center, 3-1-1 Koyadai, Tsukuba, Ibaraki, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Urano
authors.forename: Kyonoshin
authors.initials: K
authors.lastname: Maruyama
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ogata
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Morishita
authors.forename: Migiwa
authors.initials: M
authors.lastname: Takeda
authors.forename: Nozomu
authors.initials: N
authors.lastname: Sakurai
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Suzuki
authors.forename: Kazuki
authors.initials: K
authors.lastname: Saito
authors.forename: Daisuke
authors.initials: D
authors.lastname: Shibata
authors.forename: Masatomo
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Kazuko
authors.initials: K
authors.lastname: Yamaguchi-Shinozaki
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shinozaki
mesh_terms: D000040:Abscisic Acid / Q000096:biosynthesis*; D000597:Amino Acids, Branched-Chain / Q000096:biosynthesis; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D002849:Chromatography, Gas; D003681:Dehydration / Q000235:genetics*; D049308:Dioxygenases; D055864:Droughts; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D055786:Gene Knockout Techniques; D013058:Mass Spectrometry; D055442:Metabolome; D055432:Metabolomics; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins; D018749:RNA, Plant / Q000235:genetics; D013312:Stress, Physiological
chemical_list: D000597:Amino Acids, Branched-Chain; D010940:Plant Proteins; D018749:RNA, Plant; D000040:Abscisic Acid; D010105:Oxygenases; D049308:Dioxygenases; C109043:9-cis-epoxy-carotenoid dioxygenase