Oyster sex determination is influenced by temperature - First clues in spat during first gonadic differentiation and gametogenesis

The sex-determining system of Crassostrea gigas is still poorly known, especially regarding the potential influence of temperature. In order to address this question, mRNA expressions of actors of the molecular cascade (Cg-DMI, Cg-SoxE, Cg-beta-catenin, Cg-Foxl2/Cg-FoxI2os) and of Oyvlg, a germ cell...

Full description

Bibliographic Details
Published in:Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology
Main Authors: Santerre, Christelle, Sourdaine, Pascal, Marc, Nicolas, Mingant, Christian, Robert, Rene, Martinez, Anne-sophie
Format: Article in Journal/Newspaper
Language:English
Published: Elsevier Science Inc 2013
Subjects:
Oyster spat
Temperature
Sex ratio
TSD
Sex determination pathway
Crassostrea gigas
Online Access:https://archimer.ifremer.fr/doc/00136/24767/22874.pdf
https://doi.org/10.1016/j.cbpa.2013.02.007
https://archimer.ifremer.fr/doc/00136/24767/
Description
Summary:The sex-determining system of Crassostrea gigas is still poorly known, especially regarding the potential influence of temperature. In order to address this question, mRNA expressions of actors of the molecular cascade (Cg-DMI, Cg-SoxE, Cg-beta-catenin, Cg-Foxl2/Cg-FoxI2os) and of Oyvlg, a germ cell marker, were investigated by real-time PCR in spat grown at different temperatures (18, 22, 25 and 28 degrees C). In parallel, gonadic differentiation, gametogenesis and sex ratios were assessed by histology at each of these temperatures. Whatever the temperature, Cg-DMI, Cg-SoxE, Cg-beta-catenin and Oyvlg expressions peaked at the same developmental stage, always after Cg-Foxl2/Cg-Foxl2os (around 40-44 dpf for spat grown at 18 degrees C). Temperatures increased the kinetics of first gonadic differentiation and gametogenesis. At 25 degrees C a significant switch occurred in sex ratio towards males and in the balance of expression between male and female genes, in favor of males. A slight gametogenesis disturbance was also observed. These results strengthen the hypotheses about the sex-determining time window and molecular cascade governing the development of C gigas, with notably the involvement of Cg-Foxl2/Cg-Foxl2os in the very early steps. They also suggest an influence of temperature on the oyster's sex determination which, associated to genetic control, would induce a mixed sex determination system (GSD +TSD). (C) 2013 Elsevier Inc. All rights reserved.

Similar Items