Transcriptional expression levels of cell stress marker genes in the pacific oyster Crassostrea gigas exposed to acute thermal stress

• Published in: Cell Stress and Chaperones
• Main Authors: Farcy, É., Voiseux, C., Lebel, J.-M., Fiévet, B.
• Other Authors: Laboratoire de Radioécologie de Cherbourg-Octeville (LRC), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), UMR 100 Physiologie et Ecophysiologie des Mollusques Marins, IFREMER, Site Expérimental d'Argenton, Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2009
• Subjects: actin; biological marker; copper zinc superoxide dismutase; cytochrome P450; glutathione transferase; heat shock protein 70; heat shock protein 72; heat shock protein 90; messenger RNA; metallothionein; multidrug resistance protein 1; protein p53; article; cell cycle regulation; cell stress; controlled study; ebb tide; environmental temperature; gene expression; genetic transcription; heat stress; marker gene; nonhuman; nucleotide sequence; oxidative stress; oyster; priority journal; quantitative analysis; reverse transcription polymerase chain reaction; seasonal variation; summer; temperature stress; winter; animal; gene expression profiling; genetics; heat shock response; metabolism; Pacific Ocean; season; temperature; Crassostrea gigas; Ostreidae; Animals; Biological Markers; Crassostrea; Heat-Shock Response; RNA; Messenger; Pacific; Pacific oyster
• Online Access: https://hal.archives-ouvertes.fr/hal-02988579; https://doi.org/10.1007/s12192-008-0091-8

Abstract During the annual cycle, oysters are exposed to seasonal slow changes in temperature, but during emersion at low tide on sunny summer days, their internal temperature may rise rapidly, resulting in acute heat stress. We experimentally exposed oysters to a 1-h acute thermal stress and investigated the transcriptional expression level of some genes involved in cell stress defence mechanisms, including chaperone proteins (heat shock proteins Hsp70, Hsp72 and Hsp90 (HSP)), regulation of oxidative stress (Cu-Zn superoxide dismutase, metallothionein (MT)), cell detoxification (glutathione 5-transferase sigma, cytochrome P450 and multidrug resistance (MDR1)) and regulation of the cell cycle (p53). Gene mRNA levels were quantified by reverse transcription-quantitative polymerase chain reaction and expressed as their ratio to actin mRNA, used as a reference. Of the nine genes studied, HSP, MT and MDR1 mRNA levels increased in response to thermal stress. We compared the responses of oysters exposed to acute heat shock in summer and winter and observed differences in terms of magnitude and kinetics. A larger increase was observed in September, with recovery within 48 h, whereas in March, the increase was smaller and lasted more than 2 days. The results were also compared with data obtained from the natural environment. Though the functional molecule is the protein and information at the mRNA level only has limitations, the potential use of mRNAs coding for cell stress defence proteins as early sensitive biomarkers is discussed.