title: Systemic analysis of inducible target of rapamycin mutants reveal a general metabolic switch controlling growth in Arabidopsis thaliana.
abstract: The target of rapamycin (TOR) pathway is a major regulator of growth in all eukaryotes, integrating energy, nutrient and stress signals into molecular decisions. By using large-scale MS-based metabolite profiling of primary, secondary and lipid compounds in combination with array-based transcript profiling, we show that the TOR protein not only regulates growth but also influences nutrient partitioning and central energy metabolism. The study was performed on plants exhibiting conditional down-regulation of AtTOR expression, revealing strong regulation of genes involved in pathways such as the cell cycle, cell-wall modifications and senescence, together with major changes in transcripts and metabolites of the primary and secondary metabolism. In agreement with these results, our morphological and metabolic analyses disclosed major metabolic changes leading to massive accumulations of storage lipids and starch. The implications of these data in the context of the general role of TOR in eukaryotic systems are discussed in parallel with the plant-specific aspects of TOR function. Finally, we propose a role for harnessing the plant TOR pathway by utilizing it as a potent metabolic switch, offering a possible route for biotechnological optimization of plant energy content and carbon partitioning for the production of bioenergy.
authors.affiliation: Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Germany. camila.caldana@bioetanol.org.br
authors.forename: Camila
authors.initials: C
authors.lastname: Caldana
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Andrea
authors.initials: A
authors.lastname: Leisse
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Lisa
authors.initials: L
authors.lastname: Bartholomaeus
authors.forename: Alisdair R
authors.initials: AR
authors.lastname: Fernie
authors.forename: Lothar
authors.initials: L
authors.lastname: Willmitzer
authors.forename: Patrick
authors.initials: P
authors.lastname: Giavalisco
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism*; D050260:Carbohydrate Metabolism; D002241:Carbohydrates / Q000032:analysis; D015536:Down-Regulation; D004734:Energy Metabolism / Q000502:physiology; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D008055:Lipids / Q000032:analysis; D035683:MicroRNAs; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics* / Q000378:metabolism*; D030821:Plants, Genetically Modified
chemical_list: D029681:Arabidopsis Proteins; D002241:Carbohydrates; D008055:Lipids; D035683:MicroRNAs; D019869:Phosphatidylinositol 3-Kinases; C512171:TOR protein, Arabidopsis