Cloning, promoter analysis, expression and cell localization of Sox9 gene in an ovoviviparous teleost, black rockfish Sebastes schlegeli
MA Liman1, ZHANG Quanqi2, QI Jie2, LU Mengxuan1, WANG Wenji3*
1.School of Medicine, Taizhou University, Taizhou 318000, China; 2.School of Life Science, Ocean University of China, Qingdao 266003, China; 3.School of Life Science, Taizhou University, Taizhou 318000, China
Abstract: Sox9 gene was isolated from gonads of black rockfish Sebastesschlegeli(SsSox9) with body weight of (758±15)g by homology cloning and RACE technology to investigate the mechanisms of sex determination and gonadal differentiation in this ovoviviparous fish. Transcriptional factor binding sites of the Sox9 promoter were predicted, and the expression of Sox9 was analyzed by Real-time quantitative PCR and in situ hybridization (ISH). The results showed that the full-length of SsSox9 cDNA was 2039 bp, comprising of a 1461 bp open reading frame (ORF), a 336 bp 5′UTR and a 242 bp 3′UTR. The predicted SsSox9 protein of 486 aa contained a highly conserved HMG domain. Many common binding sites for transcription factor were found in Sox9 promoter, including AP-1, GATA-3, Oct-1, FOXD3, and the sex-related protein SRY, Sox5, and Sox9. qRT-PCR analysis indicated that the expression of SsSox9 was detected in all stages of 1, 5, 10, 15, 25 and 35 days after birth (DAB), with higher expression level of SsSox9 during the sensitive period of gonadal differentiation (25 DAB). The expression levels of the SsSox9 gene were sexually dimorphic in adult gonads, with higher level in testis than that in ovary. In situ hybridization revealed that SsSox9 mRNA was detected in the germ cells and Sertoli cells in the testis, and oocytes and follicular cells in the ovary, suggesting that SsSox9 may have an important role in gonadal differentiation and development of black rockfish.
2020, Vol. 35 
