Progress in studies of sex determination mechanisms and sex control techniques in Cynoglossus semilaevis (half-smooth tongue sole)

Abstract

The Cynoglossus semilaevis (half-smooth tongue sole) is a marine flatfish of great commercial value for fisheries and aquaculture in China. It has a female heterogametic sex determination system (ZW/ZZ) and environmental factors can induce sex-reversal of females to phenotypic males, suggesting that it is a promising model for the study of sex determination mechanisms. Additionally, females grow much faster than males and it is feasible to improve the aquaculture production through sex control techniques. This paper reviews the progress in research on sex determination mechanisms research in our laboratory. We have completed whole-genome sequencing and revealed the genome organization and sex chromosome evolution of C. semilaevis. A putative male determining gene dmrt1 was identified and DNA methylation was verified as having a crucial role in the sex reversal process. Genetic maps and sex-specific biomarkers have been used in a marker-assisted selection breeding program and for differentiation of the fish sex. Development and improvement of sex control technologies, including artificial gynogenesis and production of breeding fry with high proportion of females, is also reviewed. These research advances have provided insight into the regulation of sex determination and enabled efficient sex management in artificial culturing of C. semilaevis.

Keywords

Cynoglossus semilaevis / sex determination / sex control technique

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Acknowledgments

This study was supported by grants from National Natural Science Foundation of China (31130057), ‘Taishan Scholar’ Construction Project Special in Shandong Province, and Agricultural Improved Variety Project of Shandong Province.

Compliance with ethics guidelines

Qian Zhou and Songlin Chen declare that they have no conflict of interest or financial conflicts to disclose.

This article is a review and does not contain any studies with human or animal subjects performed by any of the authors.

RIGHTS & PERMISSIONS

Higher Education Press and Springer-Verlag Berlin Heidelberg