甲基睾酮与来曲唑对遗传雌性阿纳鲳鲹性逆转的诱导机制OACHSSCD

[Objective]This study aims to investigate the effects of 17α-methyltestosterone(MT)and letrozole(LZ)on gonadal histology,sex steroid hormones,and transcriptomic profiles in Trachinotus anak,and to elucidate the molecular mechanisms underlying hormone-induced sex reversal in T.anak.[Methods]Juvenile T.anak at 30 days post-hatching were fed with diets containing LZ,MT,or a con-trol diet until 6 months of age.Gonadal histology,sex hormone levels,and whole-transcriptome sequencing were analyzed,and selected differentially expressed genes were validated by quantitative real-time PCR(qPCR).[Results]Histological and serological analysis showed that LZ and MT induced phenotypic sex reversal in genetic female T.anak,with reversal rates of 6.7%and 16.7%,respectively.Compared with the male and female controls,serum estradiol and vitellogenin levels in sex-reversed individuals decreased significantly(P<0.05),while androgens(testosterone and 11-ketotestosterone)showed an upward trend,but the differences were not significant(P>0.05).Tran-scriptome sequencing yielded clean data with 198.99×109 and 185.41×106 bases,identifying 92 603 mRNAs,21 141 lncRNAs,and numerous miRNAs.Functional analysis revealed that differentially expressed genes were primarily enriched in reproduction-related pathways,particularly the oocyte meio-sis pathway.Based on this pathway,a protein-protein interaction network and lncRNA/miRNA-mRNA co-expression networks were constructed,identifying key target genes(ccne2,cul1,mad2a)and core ncRNAs(MSTRG.15985.1,MSTRG.16453.2,MSTRG.22617.1).Transcriptomic and qPCR results con-firmed that pgr,ar,and novel_miR_10 were upregulated,while cdc20,ccnb,cdc23,and several ncRNAs(e.g.,MSTRG.67400.1,novel_miR_657)were downregulated compared to normal females.[Conclusion]Both MT and LZ effectively induce phenotypic masculinization in T.anak.LZ acts pri-marily by inhibiting aromatase to disrupt estrogen synthesis and oocyte meiosis,whereas MT relies on androgen receptor signaling pathway and HPG-axis negative feedback to alter the gonadal endocrine environment.The oocyte meiosis pathway serves as the core molecular target,highlighting the critical role of oocyte remodeling in sex reversal.Non-coding RNAs precisely regulate gonadal differentiation.Given its higher efficiency,MT holds greater potential for large-scale sex-control breeding.