Differential analysis of testicular LncRNA in Kazakh horses of different ages.

The reproductive performance of horses is closely associated with testicular development, which involves a complex network of gene regulation. The molecular mechanisms underlying the reproductive traits of Kazakh horses are yet to be fully understood. In this study, transcriptomic analysis was performed on testicular tissues from Kazakh horses at different developmental stages using whole-transcriptome sequencing, aiming to investigate differential gene expression and regulatory mechanisms during testicular development. The results revealed significant differential expression of 7678 mRNAs, including COL4A1, LGR6, and WNT4, 4569 long non-coding RNAs (LncRNAs), 4148 circular RNAs (circRNAs) such as CSNK1G1, CUL3, and CSNK1G3, and 1091 microRNAs (miRNAs) including eca-miR-1197, eca-miR-122, and eca-miR-138. GO and KEGG enrichment analyses indicated that these differentially expressed genes (DEGs) are primarily involved in biological regulation (BP), cellular part (CC), binding (MF), as well as key signaling pathways such as the Wnt signaling pathway, PI3K-Akt signaling pathway, and mTOR signaling pathway. Additionally, the construction of a competing endogenous RNA (ceRNA) regulatory network highlighted the potential regulatory roles of non-coding RNAs in testicular development. This study provides a theoretical basis for analyzing the molecular mechanisms of testicular development in Kazakh horses and offers candidate molecular markers for the genetic improvement of equine reproduction.