An astroglial cell line was established from the brain of half smooth tongue sole （Cynoglossus semilaevis） and was designated as CSAC. CSAC shows the morphological homogeneity of epithelial cells. The cell identity was tested by the presence of glial fibrillary acidic protein （GFAP）, which was revealed by RT-PCR and immunofluorescence. The cell line was optimally maintained at 24 ℃ in minimum essential medium supplemented with HEPES, antibiotics, 20% fetal bovine serum, 2- Mercaptoethanol （2-Me） and basic fibroblast growth factor. Chromosome analysis revealed that the CSAC cells maintained a normal diploid chromosome number （2n=42）. The fluorescent signals were observed in CSAC after the cells were transfected with green fluorescent protein （GFP） reporter plasmids. The CSAC cell line may serve as a valuable tool for studies on the potential functions of fish astroglial cells.
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.
