Multi-omics reveals the pituitary-mediated neuroendocrine mechanisms during the transition from the onset-of-birth to the laying period in Wanxi white geese.

The dynamic remodeling of the pituitary endocrine state is a critical pivot driving the transition of the reproductive cycle in geese. In this study, pituitary tissues from Wanxi white geese at the onset-of-birth and the laying period were investigated. Using serum hormone assays, transcriptomics, and dual-luciferase reporter assays, the mRNA and miRNA expression profiles of the pituitary during these periods were constructed. The results revealed that serum levels of FSH, LH, E2, and P4 were significantly elevated during the laying compared to the onset-of-birth period. In contrast, the PRL level was significantly decreased. Integrated omics analysis identified 453 differentially expressed genes and 73 differentially expressed miRNAs. Functional enrichment analysis demonstrated that during the laying period, the pituitary mediates the robust synthesis and release of gonadotropins by activating ECM-receptor interaction, calcium and MAPK signaling pathways. Furthermore, it regulates the pituitary tissue microenvironment and upstream signal transduction through a post-transcriptional network centered on miR-32-x and miR-338-y. This network targeted key genes, including NTRK2, CAMK4, COL1A2 and ADCY2. Furthermore, dual-luciferase reporter assays supported a sequence-specific interaction between miR-338-y and the ADCY2 3'UTR. In conclusion, our findings suggest that the synergistic effect of endocrine pathways and the miRNA post-transcriptional network provides a potential multi-dimensional regulatory framework for the transduction of pituitary reproductive signals, which may drive the transition of Wanxi White geese from the onset of birth to the laying period. This study provides preliminary insights into the molecular regulatory network underlying pituitary gonadotropin secretion in poultry and identifies potential candidate targets for future breeding strategies evaluating egg-laying performance in geese.