title: System analysis of metabolism and the transcriptome in Arabidopsis thaliana roots reveals differential co-regulation upon iron, sulfur and potassium deficiency.
abstract: Deprivation of mineral nutrients causes significant retardation of plant growth. This retardation is associated with nutrient-specific and general stress-induced transcriptional responses. In this study, we adjusted the external supply of iron, potassium and sulfur to cause the same retardation of shoot growth. Nevertheless, limitation by individual nutrients resulted in specific morphological adaptations and distinct shifts within the root metabolite fingerprint. The metabolic shifts affected key metabolites of primary metabolism and the stress-related phytohormones, jasmonic, salicylic and abscisic acid. These phytohormone signatures contributed to specific nutrient deficiency-induced transcriptional regulation. Limitation by the micronutrient iron caused the strongest regulation and affected 18% of the root transcriptome. Only 130 genes were regulated by all nutrients. Specific co-regulation between the iron and sulfur metabolic routes upon iron or sulfur deficiency was observed. Interestingly, iron deficiency caused regulation of a different set of genes of the sulfur assimilation pathway compared with sulfur deficiency itself, which demonstrates the presence of specific signal-transduction systems for the cross-regulation of the pathways. Combined iron and sulfur starvation experiments demonstrated that a requirement for a specific nutrient can overrule this cross-regulation. The comparative metabolomics and transcriptomics approach used dissected general stress from nutrient-specific regulation in roots of Arabidopsis.
authors.affiliation: Centre for Organismal Studies (COS), University of Heidelberg, 69120, Heidelberg, Germany.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Forieri
authors.affiliation: Center for Medical Research, University of Mannheim, 68167, Mannheim, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Sticht
authors.affiliation: Max Planck Institute for Chemical Ecology, 07745, Jena, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Reichelt
authors.affiliation: Center for Medical Research, University of Mannheim, 68167, Mannheim, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Gretz
authors.affiliation: Rothamsted Research, Harpenden, AL5 2JQ, UK.
authors.forename: Malcolm J
authors.initials: MJ
authors.lastname: Hawkesford
authors.affiliation: Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Padua, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Malagoli
authors.affiliation: Centre for Organismal Studies (COS), University of Heidelberg, 69120, Heidelberg, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Wirtz
authors.affiliation: Centre for Organismal Studies (COS), University of Heidelberg, 69120, Heidelberg, Germany.
authors.forename: Ruediger
authors.initials: R
authors.lastname: Hell
mesh_terms: D000222:Adaptation, Physiological; D000838:Anions; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D006706:Homeostasis / Q000235:genetics; D000090463:Iron Deficiencies; D010641:Phenotype; D010937:Plant Growth Regulators / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics* / Q000378:metabolism; D011188:Potassium / Q000378:metabolism*; D013455:Sulfur / Q000172:deficiency*; D049490:Systems Biology; D014158:Transcription, Genetic; D059467:Transcriptome / Q000235:genetics*
chemical_list: D000838:Anions; D010937:Plant Growth Regulators; D013455:Sulfur; D011188:Potassium