Key regulatory genes and pathways in spermatogenesis identified by transcriptome profiling of the hypothalamic-pituitary-gonadal axis during sexual maturation in Wenchang roosters.

1. Despite the pivotal role of the hypothalamic-pituitary-gonadal (HPG) axis in avian reproduction, the underlying molecular mechanisms that govern sexual maturity and spermatogenesis in roosters are not well elucidated. This study aimed to explore gene expression changes in the HPG axis using Wenchang cockerels.2. Phenotypic results showed significant testicular growth from 18 to 20 weeks of age. Transcriptome analyses identified 2,154 differentially expressed genes (DEG) in testes, which was markedly higher than those identified in hypothalamus (52 DEG) and pituitary (27 DEG).3. Functional enrichment analysis showed neuroactive ligand-receptor interactions and hormone transport pathways in the hypothalamus and pituitary and ciliary motility and spermatogenesis pathways in the testes.4. Protein-protein interaction (PPI) networks analysis pinpointed key hub genes, such as BDNF, NPTX2, TEKT2, TEKT3, CFAP52, and MNS1, associated with spermatogenesis and sperm motility.5. This research gave insights into the genetic regulatory networks within the HPG axis that orchestrate testicular development and maturation in roosters, paving the way for potential applications in the molecular breeding of breeding roosters for reproductive optimisation.