title: Profiling of spatial metabolite distributions in wheat leaves under normal and nitrate limiting conditions.
abstract: The control and interaction between nitrogen and carbon assimilatory pathways is essential in both photosynthetic and non-photosynthetic tissue in order to support metabolic processes without compromising growth. Physiological differences between the basal and mature region of wheat (Triticum aestivum) primary leaves confirmed that there was a change from heterotrophic to autotrophic metabolism. Fourier Transform Infrared (FT-IR) spectroscopy confirmed the suitability and phenotypic reproducibility of the leaf growth conditions. Principal Component-Discriminant Function Analysis (PC-DFA) revealed distinct clustering between base, and tip sections of the developing wheat leaf, and from plants grown in the presence or absence of nitrate. Gas Chromatography-Time of Flight/Mass Spectrometry (GC-TOF/MS) combined with multivariate and univariate analyses, and Bayesian network (BN) analysis, distinguished different tissues and confirmed the physiological switch from high rates of respiration to photosynthesis along the leaf. The operation of nitrogen metabolism impacted on the levels and distribution of amino acids, organic acids and carbohydrates within the wheat leaf. In plants grown in the presence of nitrate there was reduced levels of a number of sugar metabolites in the leaf base and an increase in maltose levels, possibly reflecting an increase in starch turnover. The value of using this combined metabolomics analysis for further functional investigations in the future are discussed.
authors: School of Chemistry, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK; School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors: J William
authors: JW
authors: Allwood
authors: Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PL, UK.
authors: Surya
authors: S
authors: Chandra
authors: School of Chemistry, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK.
authors: Yun
authors: Y
authors: Xu
authors: School of Chemistry, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK; Manchester Centre for Integrative Systems Biology, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK; Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, York Place, Oxford Road, Manchester M13 9WL, UK; School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors: Warwick B
authors: WB
authors: Dunn
authors: School of Chemistry, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK.
authors: Elon
authors: E
authors: Correa
authors: School of Biology, Biomolecular Sciences Building, University of St Andrews, St Andrews, Fife, KY16 9ST Scotland, UK.
authors: Laura
authors: L
authors: Hopkins
authors: School of Chemistry, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK; Manchester Centre for Integrative Systems Biology, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK.
authors: Royston
authors: R
authors: Goodacre
authors: Vice Chancellor's Office, York St John University, Lord Mayor's Walk, York YO31 7EX, UK.
authors: Alyson K
authors: AK
authors: Tobin
authors: Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PL, UK. Electronic address: Caroline.Bowsher@manchester.ac.uk.
authors: Caroline G
authors: CG
authors: Bowsher
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D001120:Arginine / Q000032:analysis; D002241:Carbohydrates; D008401:Gas Chromatography-Mass Spectrometry; D008320:Maltose / Q000032:analysis; D009566:Nitrates / Q000032:analysis / Q000378:metabolism*; D010788:Photosynthesis; D018515:Plant Leaves / Q000737:chemistry / Q000378:metabolism*; D015203:Reproducibility of Results; D017550:Spectroscopy, Fourier Transform Infrared; D013213:Starch / Q000378:metabolism; D014908:Triticum / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D009566:Nitrates; D008320:Maltose; D013213:Starch; D001120:Arginine
keywords: Bayesian network analysis; Leaves; Metabolite fingerprinting; Metabolite profiling; Nitrate; Triticum aestivum; Wheat