title: Copper-deficiency in Brassica napus induces copper remobilization, molybdenum accumulation and modification of the expression of chloroplastic proteins.
abstract: During the last 40 years, crop breeding has strongly increased yields but has had adverse effects on the content of micronutrients, such as Fe, Mg, Zn and Cu, in edible products despite their sufficient supply in most soils. This suggests that micronutrient remobilization to edible tissues has been negatively selected. As a consequence, the aim of this work was to quantify the remobilization of Cu in leaves of Brassica napus L. during Cu deficiency and to identify the main metabolic processes that were affected so that improvements can be achieved in the future. While Cu deficiency reduced oilseed rape growth by less than 19% compared to control plants, Cu content in old leaves decreased by 61.4%, thus demonstrating a remobilization process between leaves. Cu deficiency also triggered an increase in Cu transporter expression in roots (COPT2) and leaves (HMA1), and more surprisingly, the induction of the MOT1 gene encoding a molybdenum transporter associated with a strong increase in molybdenum (Mo) uptake. Proteomic analysis of leaves revealed 33 proteins differentially regulated by Cu deficiency, among which more than half were located in chloroplasts. Eleven differentially expressed proteins are known to require Cu for their synthesis and/or activity. Enzymes that were located directly upstream or downstream of Cu-dependent enzymes were also differentially expressed. The overall results are then discussed in relation to remobilization of Cu, the interaction between Mo and Cu that occurs through the synthesis pathway of Mo cofactor, and finally their putative regulation within the Calvin cycle and the chloroplastic electron transport chain.
authors.affiliation: Normandie Université, Caen, France; UNICAEN, UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, Caen, France; INRA, UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, Caen, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Billard
authors.affiliation: Normandie Université, Caen, France; UNICAEN, UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, Caen, France; INRA, UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, Caen, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Ourry
authors.affiliation: Normandie Université, Caen, France; UNICAEN, UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, Caen, France; INRA, UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, Caen, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Maillard
authors.affiliation: Timac Agro Spain, Poligono de Arazuri-Orcoyen, Orcoyen, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Garnica
authors.affiliation: Plateforme de protéomique PISSARO, UMR6270 CNRS Faculté des Sciences de Rouen, Mont-Saint-Aignan, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Coquet
authors.affiliation: Plateforme de protéomique PISSARO, UMR6270 CNRS Faculté des Sciences de Rouen, Mont-Saint-Aignan, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Jouenne
authors.affiliation: Centre de Recherche International en Agroscience, CRIAS-TAI, Groupe Roullier, Dinard, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Cruz
authors.affiliation: Timac Agro Spain, Poligono de Arazuri-Orcoyen, Orcoyen, Spain.
authors.forename: José-Maria
authors.initials: JM
authors.lastname: Garcia-Mina
authors.affiliation: Centre de Recherche International en Agroscience, CRIAS-TAI, Groupe Roullier, Dinard, France.
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Yvin
authors.affiliation: Normandie Université, Caen, France; UNICAEN, UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, Caen, France; INRA, UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, Caen, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Etienne
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D027321:Anion Transport Proteins / Q000378:metabolism; D029688:Brassica napus / Q000378:metabolism*; D060365:Chloroplast Proteins / Q000378:metabolism*; D002736:Chloroplasts / Q000378:metabolism*; D003300:Copper / Q000172:deficiency* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D026901:Membrane Transport Proteins / Q000378:metabolism; D008982:Molybdenum / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D040901:Proteomics
chemical_list: D027321:Anion Transport Proteins; D060365:Chloroplast Proteins; D026901:Membrane Transport Proteins; D010940:Plant Proteins; D003300:Copper; D008982:Molybdenum; D000251:Adenosine Triphosphatases