Metabolic fingerprinting of the responses to salinity in the invasive ground beetle Merizodus soledadinus at the Kerguelen Islands

• Published in: Journal of Insect Physiology
• Main Authors: Hidalgo, Kévin, Laparie, Mathieu, Bical, Raphael, Larvor, Vanessa, Bouchereau, Alain, Siaussat, David, Renault, David
• Other Authors: Ecosystèmes, biodiversité, évolution Rennes (ECOBIO), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Paysage, Changements Climatiques, Biodiversité, Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Station Biologique de Paimpont CNRS UMR 6653 (OSUR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES), APBV, Amélioration des Plantes et Biotechnologies Végétales (APBV), Institut National de la Recherche Agronomique (INRA)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de la Recherche Agronomique (INRA)-Université de Rennes 1 (UR1), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Physiologie de l'Insecte : Signalisation et Communication (PISC), Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech, IPEV programme 136; Zone Atelier CNRS Antarctique et Subantarctique, ANR-07-VULN-0004,EVINCE,Vulnerability of native communities to invasive insects and climate change in sub-antarctic islands.(2007)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: Amino acid; Survival; Glycine; Compatible solutes; Osmoregulation; Alanine; Body water content; Biological invasions; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Kerguelen; Kerguelen Islands
• Online Access: https://hal.archives-ouvertes.fr/hal-00801308; https://doi.org/10.1016/j.jinsphys.2012.10.017

International audience Salinity is an abiotic factor that may impact survival and fitness of terrestrial insects in coastal environments. Meanwhile, some terrestrial arthropods can survive in hypersaline environments, and counterbalance osmotic stress by intra- and extracellular buildups of organic osmolytes. The ground beetle Merizodus soledadinus originates from South America and it is distributed in forests and riparian zones, where salinity levels are considerably low. This species has been introduced at the Kerguelen Islands a century ago, where it colonized coastal areas (tide drift lines), and must thus withstand salinity variations due to tide, spray, and organic matter deposited therein. In the present study, we addressed the physiological plasticity of M. soledadinus to saline conditions, by monitoring body water content and survival in adults experimentally subjected to different salinities. We also investigated possible metabolic adjustments involved at three contrasted salinity levels (0‰, 35‰, 70‰) at 4 and 8 C. We hypothesized that this invasive ground beetle can withstand a broad range of salinity conditions thanks to the plastic accumulation of compatible solutes. The study revealed a progressive drop in body water content in individuals exposed to 35‰ and 70‰, as opposed to the controls. Metabolic fingerprints showed compatible solute (erythritol, alanine, glycine and proline) accumulation at medium and high salinity conditions (35‰ and 70‰). We concluded that the osmo-induced accumulation of amino acids and polyols was likely to modulate the ground beetles' body water balance on medium saline substrates, thus enhancing their survival ability.