title: Modulation of copper deficiency responses by diurnal and circadian rhythms in Arabidopsis thaliana.
abstract: Copper homeostasis under deficiency is regulated by the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE7 (SPL7) transcription factor. The daily oscillating expression of two SPL7-dependent copper deficiency markers, COPPER TRANSPORTER (COPT2) and IRON SUPEROXIDE DISMUTASE (FSD1), has been followed by quantitative PCR and in promoter:LUCIFERASE transgenic plants. Both genes showed circadian and diurnal regulation. Under copper deficiency, their expression decreased drastically in continuous darkness. Accordingly, total copper content was slightly reduced in etiolated seedlings under copper deficiency. The expression of SPL7 and its targets COPT2 and FSD1 was differently regulated in various light signalling mutants. On the other hand, increased copper levels reduced the amplitude of nuclear circadian clock components, such as GIGANTEA (GI). The alteration of copper homeostasis in the COPT1 overexpression line and spl7 mutants also modified the amplitude of a classical clock output, namely the circadian oscillation of cotyledon movements. In the spl7 mutant, the period of the oscillation remained constant. These results suggest a feedback of copper transport on the circadian clock and the integration of rhythmic copper homeostasis into the central oscillator of plants.
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Universitat de València, Av. Doctor Moliner, 50, ES-46100 Burjassot, Valencia, Spain * Present address: IIB-INTECh UNSAM-CONICET CC 164 (7130), Chascomús, Argentina.
authors.forename: Ana
authors.initials: A
authors.lastname: Perea-García
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Universitat de València, Av. Doctor Moliner, 50, ES-46100 Burjassot, Valencia, Spain.
authors.forename: Amparo
authors.initials: A
authors.lastname: Andrés-Bordería
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Universitat de València, Av. Doctor Moliner, 50, ES-46100 Burjassot, Valencia, Spain Present address: Unidad de Genética y Diagnóstico Prenatal, Hospital Universitario y Politécnico La Fe, Av. Campanar 21, ES-46009 Valencia, Spain.
authors.forename: Sonia
authors.initials: S
authors.lastname: Mayo de Andrés
authors.affiliation: Departament de Biologia Vegetal, Universitat de València, Av. Doctor Moliner, 50, ES-46100 Burjassot, Valencia, Spain.
authors.forename: Amparo
authors.initials: A
authors.lastname: Sanz
authors.affiliation: Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829 Cologne, Germany Department of Biology, University of York, UK.
authors.forename: Amanda M
authors.initials: AM
authors.lastname: Davis
authors.affiliation: Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829 Cologne, Germany Department of Biology, University of York, UK.
authors.forename: Seth J
authors.initials: SJ
authors.lastname: Davis
authors.affiliation: Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829 Cologne, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Huijser
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Universitat de València, Av. Doctor Moliner, 50, ES-46100 Burjassot, Valencia, Spain penarrub@uv.es.
authors.forename: Lola
authors.initials: L
authors.lastname: Peñarrubia
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D027682:Cation Transport Proteins / Q000235:genetics* / Q000378:metabolism; D002940:Circadian Rhythm; D003300:Copper / Q000172:deficiency / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D006706:Homeostasis; D030821:Plants, Genetically Modified / Q000235:genetics / Q000502:physiology; D000080083:SLC31 Proteins; D013482:Superoxide Dismutase / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C585190:COPT2 protein, Arabidopsis; D027682:Cation Transport Proteins; D004268:DNA-Binding Proteins; D000080083:SLC31 Proteins; C483288:SPL7 protein, Arabidopsis; D014157:Transcription Factors; D003300:Copper; D013482:Superoxide Dismutase
keywords: Arabidopsis thaliana; circadian clock; copper deficiency; copper transport; diurnal rhythm; heavy metals.