Transcriptomic Dynamics and ECM Remodeling During Postnatal Testicular Maturation in the Tianzhu White Yak

Abstract

Simple Summary Yaks (Bos grunniens) are vital to the livelihoods of pastoral communities on the Qinghai–Tibetan Plateau; however, their reproductive performance is constrained by late sexual maturity, strong seasonal breeding patterns, and low conception rates. A better understanding of the molecular mechanisms underlying testicular development may facilitate the development of strategies to improve yak fertility. In this study, we analyzed gene expression profiles in the testes of Tianzhu white yaks at three key developmental stages: prepuberty (0.5 years), puberty (2.5 years), and adulthood (4.5 years). The most pronounced transcriptional changes occurred during the transition from prepuberty to puberty, involving nearly 10,000 genes, whereas comparatively few genes changed between puberty and adulthood. Gene network analysis identified groups of co-regulated genes associated with spermatogenesis, and functional analyses revealed that remodeling of the cellular scaffold (extracellular matrix) may play an important role during this critical developmental period. These findings provide a comprehensive molecular framework for understanding testicular maturation in yaks and identify biological pathways that may serve as potential targets for improving reproductive performance.