title: Peroxiredoxin 2 nuclear levels are regulated by circadian clock synchronization in human keratinocytes.
abstract: Circadian rhythms are highly conserved time tracking systems regulating important biological processes at both systemic and cellular levels. The present study was aimed to identify proteins and biological functions circadian regulated in human keratinocytes. HaCaT keratinocytes were entrained by temperature cycles, and a proteomic study was performed on cell fractions isolated under free running conditions at constant temperature. Bioinformatics analysis revealed that molecular clock entrainment was associated with changes in molecular components regulating cell proliferation, energy metabolism, transcription, translation and redox balance. Nuclear levels of the antioxidant enzyme Peroxiredoxin 2 (PRDX2) were found to oscillate rhythmically over two entire 24h long cycles. Donwregulation of PRDX2 resulted in upregulation of the mitochondrion-specific Peroxiredoxin 3 (PRDX3), all other members of the Peroxiredoxin family remained unaltered. Furthermore, PRDX2 knockdown increased intracellular levels of reactive oxygen species (ROS) and impaired cell cycle progression and proliferation. HaCaT cells transduced with a scramble shRNA were used as control. Our work is the first to show that nuclear levels of PRDX2 display circadian oscillation participating in the regulation of human keratinocytes redox balance.
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Medicina Clinica e Molecolare, Sapienza Università di Roma, Rome, Italy; Laboratiorio Biologia Vascolare e Medicina Rigenerativa, Centro Cardiologico Monzino - IRCCS, Milan, Italy. Electronic address: daniele.avitabile@uniroma1.it.
authors.forename: Daniele
authors.initials: D
authors.lastname: Avitabile
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Medicina Clinica e Molecolare, Sapienza Università di Roma, Rome, Italy.
authors.forename: Danilo
authors.initials: D
authors.lastname: Ranieri
authors.affiliation: Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Rome, Italy.
authors.forename: Arianna
authors.initials: A
authors.lastname: Nicolussi
authors.affiliation: Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Rome, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: D'Inzeo
authors.affiliation: Dipartimento di Chimica, Sapienza Università di Roma, Rome, Italy.
authors.forename: Anna Laura
authors.initials: AL
authors.lastname: Capriotti
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Medicina Clinica e Molecolare, Sapienza Università di Roma, Rome, Italy.
authors.forename: Licia
authors.initials: L
authors.lastname: Genovese
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Medicina Clinica e Molecolare, Sapienza Università di Roma, Rome, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Proietti
authors.affiliation: Dipartimento di Chirurgia"P. Valdoni", Sapienza Università di Roma, Rome, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Cucina
authors.affiliation: Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Rome, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Coppa
authors.affiliation: Dipartimento di Chimica, Sapienza Università di Roma, Rome, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Samperi
authors.affiliation: Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Rome, Italy.
authors.forename: Mariano
authors.initials: M
authors.lastname: Bizzarri
authors.affiliation: Dipartimento di Chimica, Sapienza Università di Roma, Rome, Italy.
authors.forename: Aldo
authors.initials: A
authors.lastname: Laganà
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Medicina Clinica e Molecolare, Sapienza Università di Roma, Rome, Italy; Azienda Ospedaliera S. Andrea, Rome, Italy.
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Torrisi
mesh_terms: D059447:Cell Cycle Checkpoints / Q000235:genetics*; D049109:Cell Proliferation / Q000235:genetics*; D057906:Circadian Clocks / Q000235:genetics*; D004734:Energy Metabolism / Q000235:genetics; D005786:Gene Expression Regulation; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism; D009687:Nuclear Proteins / Q000096:biosynthesis; D054464:Peroxiredoxins / Q000096:biosynthesis / Q000235:genetics*; D040901:Proteomics; D017382:Reactive Oxygen Species
chemical_list: D009687:Nuclear Proteins; D017382:Reactive Oxygen Species; D054464:Peroxiredoxins
keywords: Circadian rhythm; HaCaT keratinocytes; Metabolic clock; Nano-LC–MS/MS; Peroxiredoxin 2; Proteomic analysis