title: Molybdenum and iron mutually impact their homeostasis in cucumber (Cucumis sativus) plants.
abstract: Molybdenum (Mo) and iron (Fe) are essential micronutrients required for crucial enzyme activities in plant metabolism. Here we investigated the existence of a mutual control of Mo and Fe homeostasis in cucumber (Cucumis sativus). Plants were grown under single or combined Mo and Fe starvation. Physiological parameters were measured, the ionomes of tissues and the ionomes and proteomes of root mitochondria were profiled, and the activities of molybdo-enzymes and the synthesis of molybdenum cofactor (Moco) were evaluated. Fe and Mo were found to affect each other's total uptake and distribution within tissues and at the mitochondrial level, with Fe nutritional status dominating over Mo homeostasis and affecting Mo availability for molybdo-enzymes in the form of Moco. Fe starvation triggered Moco biosynthesis and affected the molybdo-enzymes, with its main impact on nitrate reductase and xanthine dehydrogenase, both being involved in nitrogen assimilation and mobilization, and on the mitochondrial amidoxime reducing component. These results, together with the identification of > 100 proteins differentially expressed in root mitochondria, highlight the central role of mitochondria in the coordination of Fe and Mo homeostasis and allow us to propose the first model of the molecular interactions connecting Mo and Fe homeostasis.
authors.affiliation: Department of Agricultural and Environmental Sciences, University of Milano, via Celoria 2, 20133, Milano, Italy.
authors.forename: Gianpiero
authors.initials: G
authors.lastname: Vigani
authors.affiliation: Proteomic and Metabolomic Laboratory, Institute of Biomedical Technologies, National Research Council (ITB-CNR), via F.lli Cervi 93, 20090, Segrate (MI), Italy.
authors.forename: Dario
authors.initials: D
authors.lastname: Di Silvestre
authors.affiliation: Proteomic and Metabolomic Laboratory, Institute of Biomedical Technologies, National Research Council (ITB-CNR), via F.lli Cervi 93, 20090, Segrate (MI), Italy.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Agresta
authors.affiliation: Department of Agricultural and Environmental Sciences, University of Milano, via Celoria 2, 20133, Milano, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Donnini
authors.affiliation: Proteomic and Metabolomic Laboratory, Institute of Biomedical Technologies, National Research Council (ITB-CNR), via F.lli Cervi 93, 20090, Segrate (MI), Italy.
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Mauri
authors.affiliation: Institute of Horticulture Production Systems, Leibniz University of Hannover, Herrenhaeuser Str. 2, 30419, Hannover, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Gehl
authors.affiliation: Department of Plant Biology, Braunschweig University of Technology, Spielmannstrasse 7, 38106, Braunschweig, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Bittner
authors.affiliation: Department of Biosciences, University of Milano, via Celoria 26, 20133, Milano, Italy.
authors.forename: Irene
authors.initials: I
authors.lastname: Murgia
mesh_terms: D016000:Cluster Analysis; D003067:Coenzymes / Q000378:metabolism; D018553:Cucumis sativus / Q000187:drug effects / Q000378:metabolism*; D005560:Formate Dehydrogenases / Q000378:metabolism; D006706:Homeostasis / Q000187:drug effects*; D007501:Iron / Q000494:pharmacology*; D055442:Metabolome / Q000187:drug effects; D008667:Metalloproteins / Q000378:metabolism; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000378:metabolism; D008954:Models, Biological; D008982:Molybdenum / Q000494:pharmacology*; D000090006:Molybdenum Cofactors; D010088:Oxidoreductases / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D020543:Proteome / Q000378:metabolism; D011621:Pteridines / Q000378:metabolism
chemical_list: D003067:Coenzymes; D005560:Formate Dehydrogenases; D007501:Iron; D008667:Metalloproteins; D024101:Mitochondrial Proteins; D008982:Molybdenum; D000090006:Molybdenum Cofactors; D010088:Oxidoreductases; D020543:Proteome; D011621:Pteridines; C022261:molybdopterin
keywords: Cucumis sativus (cucumber); ionomics; iron (Fe); micronutrient homeostasis; mitochondria; molybdenum (Mo); molybdo-enzymes