title: Comprehensive dissection of spatiotemporal metabolic shifts in primary, secondary, and lipid metabolism during developmental senescence in Arabidopsis.
abstract: Developmental senescence is a coordinated physiological process in plants and is critical for nutrient redistribution from senescing leaves to newly formed sink organs, including young leaves and developing seeds. Progress has been made concerning the genes involved and the regulatory networks controlling senescence. The resulting complex metabolome changes during senescence have not been investigated in detail yet. Therefore, we conducted a comprehensive profiling of metabolites, including pigments, lipids, sugars, amino acids, organic acids, nutrient ions, and secondary metabolites, and determined approximately 260 metabolites at distinct stages in leaves and siliques during senescence in Arabidopsis (Arabidopsis thaliana). This provided an extensive catalog of metabolites and their spatiotemporal cobehavior with progressing senescence. Comparison with silique data provides clues to source-sink relations. Furthermore, we analyzed the metabolite distribution within single leaves along the basipetal sink-source transition trajectory during senescence. Ceramides, lysolipids, aromatic amino acids, branched chain amino acids, and stress-induced amino acids accumulated, and an imbalance of asparagine/aspartate, glutamate/glutamine, and nutrient ions in the tip region of leaves was detected. Furthermore, the spatiotemporal distribution of tricarboxylic acid cycle intermediates was already changed in the presenescent leaves, and glucosinolates, raffinose, and galactinol accumulated in the base region of leaves with preceding senescence. These results are discussed in the context of current models of the metabolic shifts occurring during developmental and environmentally induced senescence. As senescence processes are correlated to crop yield, the metabolome data and the approach provided here can serve as a blueprint for the analysis of traits and conditions linking crop yield and senescence.
authors.affiliation: Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany. watanabe@mpimp-golm.mpg.de
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Watanabe
authors.forename: Salma
authors.initials: S
authors.lastname: Balazadeh
authors.forename: Takayuki
authors.initials: T
authors.lastname: Tohge
authors.forename: Alexander
authors.initials: A
authors.lastname: Erban
authors.forename: Patrick
authors.initials: P
authors.lastname: Giavalisco
authors.forename: Joachim
authors.initials: J
authors.lastname: Kopka
authors.forename: Bernd
authors.initials: B
authors.lastname: Mueller-Roeber
authors.forename: Alisdair R
authors.initials: AR
authors.lastname: Fernie
authors.forename: Rainer
authors.initials: R
authors.lastname: Hoefgen
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D017360:Arabidopsis / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D050260:Carbohydrate Metabolism; D002734:Chlorophyll / Q000032:analysis / Q000378:metabolism; D020869:Gene Expression Profiling; D050356:Lipid Metabolism; D055442:Metabolome; D010860:Pigments, Biological / Q000378:metabolism; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D012639:Seeds / Q000254:growth & development / Q000378:metabolism
chemical_list: D000596:Amino Acids; D010860:Pigments, Biological; D002734:Chlorophyll