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Updated: Jul 15, 2026

Dissection of Larval Zebrafish Gonadal Tissue
Published on: April 26, 2017
Transcriptomic analysis suggests FoxO and steroid hormone biosynthesis pathways are associated with
Da Zheng1,2, Huapeng Chen1, Huan Liang1
1School of Marine Biology and Fisheries, Hainan Aquaculture Breeding Engineering Research Center, Collaborative Innovation Center of Nanfan and High-Efficiency Tropical Agriculture, Hainan University, Haikou, 570228, China.
Abstract:
This study investigated the effects of dietary 17α-methyltestosterone (MT) on gonadal differentiation and transcriptomic changes associated with partial masculinization in Trachinotus blochii. Larvae (3 days post-hatching) were fed a diet containing 100 mg/kg MT for 60 days. The results showed that MT treatment induced intersex gonadal development in 73% of genetic females, with gonads characterized by the presence of spermatogonia. Hormone assays showed increased MT levels and reduced 17β-estradiol (E2) levels in MT-treated intersex individuals compared with control females. Compared with control females, MT-treated intersex individuals showed increased expression of male-associated genes, including cyp11b1, sf1, and dmrt1, whereas cyp19a1a was reduced. However, other female-associated genes, such as hsd17β1 and foxl2, were not completely suppressed. Transcriptome profiling identified significant enrichment of FoxO-related and steroid hormone biosynthesis pathways. Trend analysis suggested that changes in oocyte meiosis-related and steroid hormone biosynthesis-related genes may be associated with MT-induced gonadal remodeling. These findings provide transcriptomic evidence for pathways potentially associated with MT-induced intersex gonadal development and may inform future studies on sex-control strategies in T. blochii, although fertility testing and reproductive validation of these intersex individuals are still required.
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