Pituitary transcriptome analysis of spotted scat (Scatophagus argus) with ovaries before and after yolk formation

Fish eggs are of pivotal significance in the domain of fish reproduction, and the degree of their development exerts a profound effect on reproductive capacity. Spotted scat (Scatophagus argus) is an important economic mariculture fish in East and Southeast Asia. Previous research has focused on how pituitary hormones are expressed and released during ovarian development. However, few studies have examined how the pituitary gland controls the expression of hormone genes during the development of the ovaries. In this study, the focus was on the analysis of the transcriptome profiles of pituitary glands in spotted scat. The analysis was conducted on female specimens with ovaries in two distinct states: before yolk formation (BYF) and after yolk formation (AYF). The results reveal that 149 differentially expressed genes (DEGs) were identified between BYF and AYF. Compared to the BYF stage, 85 genes were found to be up-regulated, while 64 genes were down-regulated in the AYF. Notably, some genes' expression level has alteration. Such as hormone receptors (gnrhr2 and ar), promote ovarian development genes (cga, cgba, fshb, lhb), estrogen synthase and regulated genes (cyp19a1, hdac9b, and gadd45b), hormone regulation (fgfr4). Additionally, changes have been observed in nociceptive inhibitory and appetite-related genes (e.g. tmem100 and reln). GO and KEGG enrichment analysis revealed that the PI3K-AKT signaling pathway is implicated in the regulation of pituitary hormones. The transcriptomic data provide valuable insights for further study of the regulatory role of the pituitary gland in the ovarian development of spotted scat and provide data support for better artificial regulation of ovarian development and egg maturation in captive breeding of spotted scat.