title: The nuclear phenotypic plasticity observed in fish during rRNA regulation entails Cajal bodies dynamics.
abstract: Cajal bodies (CBs) are small mobile organelles found throughout the nucleoplasm of animal and plant cells. The dynamics of these organelles involves interactions with the nucleolus. The later has been found to play a substantial role in the compensatory response that evolved in eurythermal fish to adapt to the cyclic seasonal habitat changes, i.e., temperature and photoperiod. Contrary to being constitutive, rRNA synthesis is dramatically regulated between summer and winter, thus affecting ribosomal biogenesis which plays a central role in the acclimatization process. To examine whether CBs, up to now, never described in fish, were also sustaining the phenotypic plasticity observed in nuclei of fish undergoing seasonal acclimatization, we identified these organelles both, by transmission electronic microscopy and immunodetection with the marker protein p80-coilin. We found transcripts in all tissues analyzed. Furthermore we assessed that p80-coilin gene expression was always higher in summer-acclimatized fish when compared to that adapted to the cold season, indicating that p80-coilin expression is modulated upon seasonal acclimatization. Concurrently, CBs were more frequently found in summer-acclimatized carp which suggests that the organization of CBs is involved in adaptive processes and contribute to the phenotypic plasticity of fish cell nuclei observed concomitantly with profound reprogramming of nucleolar components and regulation of ribosomal rRNAs.
authors.affiliation: Department of Biological Sciences, Universidad Andres Bello, and Millennium Institute for Fundamental and Applied Biology, Santiago, Chile.
authors.forename: Marco
authors.initials: M
authors.lastname: Alvarez
authors.forename: Gino
authors.initials: G
authors.lastname: Nardocci
authors.forename: Marc
authors.initials: M
authors.lastname: Thiry
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Alvarez
authors.forename: Mauricio
authors.initials: M
authors.lastname: Reyes
authors.forename: Alfredo
authors.initials: A
authors.lastname: Molina
authors.forename: M Ines
authors.initials: MI
authors.lastname: Vera
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D000818:Animals; D002347:Carps / Q000502:physiology*; D002467:Cell Nucleus / Q000502:physiology*; D020541:Coiled Bodies / Q000502:physiology*; D008297:Male; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D014176:Protein Biosynthesis / Q000502:physiology; D012335:RNA, Ribosomal / Q000378:metabolism*
chemical_list: D009687:Nuclear Proteins; D012335:RNA, Ribosomal; C068921:p80-coilin