Phenotypic plasticity in the symbiotic cnidarian Anemonia viridis : stress response at multiple levels of structural complexity

• Main Author: Ventura, Patrícia Nobre Montenegro
• Other Authors: Evolution Paris Seine, Université des Antilles et de la Guyane (UAG)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS)-Centre National de la Recherche Scientifique (CNRS), COMUE Université Côte d'Azur (2015 - 2019), Stéphanie Barnay-Verdier, Paola Furla
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: HAL CCSD 2016
• Subjects: Symbiotic Cnidarian; Phenotypic plasticity; Acidification; Culture cells; Cnidaire symbiotique; Plasticité phénotypique; Culture des cellules; [SDV.SA]Life Sciences [q-bio]/Agricultural sciences; Ocean acidification
• Online Access: https://theses.hal.science/tel-01674220; https://theses.hal.science/tel-01674220/document; https://theses.hal.science/tel-01674220/file/2016AZUR4136.pdf

During the course of their life cycle organisms are exposed to natural environment variations capable of inducing physiological, morphological and behaviour changes, thus a phenotypic plasticity. Phenotypic plasticity is the ability of a genotype to generate a new phenotype following exogeneous or endogeneous stress. Here, we investigated the phenotypic plasticity of the non-calcifying symbiotic cnidarian Anemonia viridis at multiple levels of structural complexity, in vivo and in vitro. In vivo, we determined the mechanisms behind the phenotypic plasticity under expected future climate change (i.e. ocean acidification and ocean warming). Our results show physiological changes in the inorganic carbon use of the sea anemone A. viridis exposed to high pCO2 during a long-term stress in natura or a short-term stress in controlled conditions. We then observed an equivalent decrease in carbonic anhydrase activity, a key enzyme of cnidarian carbon concentrating mechanisms. Also, we demonstrated that an increase in seawater temperature modified the response observed during a high pCO2 scenario. In vitro, we established a viable primary cell culture from regenerating tentacles of A. viridis. We determined the gastrodermal tissue origin of the cultivated cells and validated the use of this new tool to the in vitro study of stress response at the cellular level. The set-up of this powerful in vitro tool will open a multitude of perspectives for the study of cellular responses to exogeneous stress (as global change perturbations) and to endogeneous stress (as the symbiosis constraints experienced by symbiotic cnidarians) Durant leur cycle de vie, les organismes sont exposés à des variations environnementales capables d'induire des changements physiologiques, morphologiques et comportementaux, résultant d’une plasticité phénotypique. La plasticité phénotypique est la capacité d'un génotype à générer un nouveau phénotype suite à un stress. Ici, nous avons étudié la plasticité phénotypique d’un Cnidaire symbiotique et ...