Single-cell analysis reveals cellular heterogeneity and molecular features during postnatal pig testis development.

BACKGROUND

Postnatal testicular development involves the proliferation and differentiation of somatic and spermatogenic cells. The entire process is governed by spatial and temporal cues that coordinate spermatogenesis. Comparative analyses of gene expression and transcriptional regulation across multiple stages can provide insights into the complexity of developmental dynamics. Therefore, we systematically analyzed the cellular composition and molecular features of boar testes at different time points using single-cell RNA sequencing (scRNA-seq) to reveal their roles in testicular development.

RESULTS

We performed scRNA-seq on 115,248 testicular cells from eight pigs at 0, 2, 5, 24, and 48 months of age, identifying 10 distinct cell types, including three rare populations: pericytes, smooth muscle cells, and neutrophils. Trajectory analysis and RNA velocity modeling uncovered dynamic cell fate transitions during spermatogenesis. Furthermore, we identified testis cell-specific transcription factors and regulators. Notably, PRDX5 and LUZP2 exhibited developmental stage-specific expression after M5 and varied with the proportion of germ cells. Cross-species comparative analysis revealed the evolutionary conservation among testicular cell populations, especially endothelial and germ cells, and identified several conserved transcription factors such as SOX9, IRF8, and KDM5B, highlighting conserved regulatory mechanisms during testicular development.

CONCLUSIONS

Our findings provide novel insights into the cellular dynamics of spermatogenesis and offer a valuable foundation for future research on the molecular mechanisms underlying testicular development in pigs and other mammals.