title: Solanum tuberosum ZPR1 encodes a light-regulated nuclear DNA-binding protein adjusting the circadian expression of StBBX24 to light cycle.
abstract: ZPR1 proteins belong to the C4-type of zinc finger coordinators known in animal cells to interact with other proteins and participate in cell growth and proliferation. In contrast, the current knowledge regarding plant ZPR1 proteins is very scarce. Here, we identify a novel potato nuclear factor belonging to this family and named StZPR1. StZPR1 is specifically expressed in photosynthetic organs during the light period, and the ZPR1 protein is located in the nuclear chromatin fraction. From modelling and experimental analyses, we reveal the StZPR1 ability to bind the circadian DNA cis motif 'CAACAGCATC', named CIRC and present in the promoter of the clock-controlled double B-box StBBX24 gene, the expression of which peaks in the middle of the day. We found that transgenic lines silenced for StZPR1 expression still display a 24 h period for the oscillation of StBBX24 expression but delayed by 4 h towards the night. Importantly, other BBX genes exhibit altered circadian regulation in these lines. Our data demonstrate that StZPR1 allows fitting of the StBBX24 circadian rhythm to the light period and provide evidence that ZPR1 is a novel clock-associated protein in plants necessary for the accurate rhythmic expression of specific circadian-regulated genes.
authors.affiliation: Institute of Plant Genetics, Polish Academy of Sciences, Strzeszyńska 34, 60-479, Poznań, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Kiełbowicz-Matuk
authors.affiliation: Institute of Plant Genetics, Polish Academy of Sciences, Strzeszyńska 34, 60-479, Poznań, Poland.
authors.forename: Jagoda
authors.initials: J
authors.lastname: Czarnecka
authors.affiliation: Molecular Biophysics Department, Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614, Poznań, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Banachowicz
authors.affiliation: CEA, DRF, BIAM, Laboratoire d'Ecophysiologie Moléculaire des Plantes, Saint-Paul-lez-Durance, F-13108, France.|CNRS, UMR 7265 Biologie Végétale & Microbiologie Environnementale, Saint-Paul-lez-Durance, F-13108, France.|Aix-Marseille Université, Saint-Paul-lez-Durance, F-13108, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Rey
authors.affiliation: Institute of Plant Genetics, Polish Academy of Sciences, Strzeszyńska 34, 60-479, Poznań, Poland.
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Rorat
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D002467:Cell Nucleus / Q000378:metabolism* / Q000528:radiation effects; D002940:Circadian Rhythm / Q000235:genetics / Q000528:radiation effects*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004777:Environment; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing / Q000187:drug effects; D008027:Light; D059372:Nucleotide Motifs / Q000235:genetics; D010802:Phylogeny; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D000072417:Protein Domains; D021381:Protein Transport; D011198:Solanum tuberosum / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects*; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D010940:Plant Proteins; D000040:Abscisic Acid
keywords: C4-type zinc finger transcription factor; Solanum tuberosum; ZPR1 domain; circadian clock; double B-box protein; silencing