Genome-Wide Identification, Sequence Alignment, and Transcription of Five Sex-Related Genes in Largemouth Bass ( Micropterus Salmoides )

• Published in: Frontiers in bioscience (Landmark. Print) 2024-02, Vol.29 (2), p.63-63
• Main Authors: Zhang, Xinhui, Ruan, Zhiqiang, Sun, Chengfei, Hu, Cancan, Huang, Yu, You, Xinxin, Wang, Xinwen, Xu, Junmin, Liu, Huan, Liu, Xin, Ye, Xing, Shi, Qiong
• Format: Article
• Language: English
• Subjects: Animals; Bass - genetics; differentially expressed genes; Female; gonadal development; largemouth bass; Male; Ovary; Sequence Alignment; sex-related gene; Testis; Transcriptome; transcriptome sequencing
• ISSN: 2768-6701; 2768-6698
• DOI: 10.31083/j.fbl2902063

Largemouth bass ( ) is an economically important fish species in China. Most research has focused on its growth, disease resistance, and nutrition improvement. However, the sex-determining genes in largemouth bass are still unclear. The transforming growth factor-beta (TGF-β) gene family, including , and , plays an important role in the sex determination and differentiation of various fishes. These genes are potentially involved in sex determination in largemouth bass. We performed a systematic analysis of 5 sex-related genes ( , , , , ) in largemouth bass using sequence alignment, collinearity analysis, transcriptome, and quantitative real-time polymerase chain reaction (qRT-PCR). This included a detailed assessment of their sequences, gene structures, evolutionary traits, and gene transcription patterns in various tissues including gonads, and at different developmental stages. Comparative genomics revealed that the 5 sex-related genes were highly conserved in various fish genomes. These genes did not replicate, mutate or lose in largemouth bass. However, some were duplicated ( , and ), mutated ( ) or lost ( ) in other fishes. Some genes (e.g., ) showed significant differences in genomic sequence between males and females, which may contribute to sex determination and sex differentiation in these fishes. qRT-PCR was applied to quantify transcription profiling of the 5 genes during gonadal development and in the adult largemouth bass. Interestingly, , and were predominantly expressed in the testis, while and were mainly transcribed in the ovary. All 5 sex-related genes were differentially expressed in the testes and ovaries from the 56th day post-fertilization (dpf). We therefore speculate that male/female differentiation in the largemouth bass may begin at this critical time-point. Examination of the transcriptome data also allowed us to screen out several more sex-related candidate genes. Our results provide a valuable genetic resource for investigating the physiological functions of these 5 sex-related genes in sex determination and gonadal differentiation, as well as in the control of gonad stability in adult largemouth bass.