Abstract
BACKGROUND: Yaks (Bos grunniens), native to the high-altitude environments of the Qinghai-Tibet Plateau, are crucial livestock for local herders, providing milk, meat, and other resources. However, traditional grazing practices are becoming increasingly unsustainable due to overgrazing and land degradation. This study investigates the impact of different feeding systems on yak skeletal muscle development and meat quality, focusing on the role of long non-coding RNAs (lncRNAs) in regulating these processes. Using a multi-omics approach, we constructed a comprehensive competing endogenous RNA (ceRNA) network comprising lncRNAs, miRNAs, and mRNAs. Differentially expressed lncRNAs were identified and their regulatory functions assessed. RESULTS: We identified a total of 2,009 lncRNA transcripts in yak skeletal muscle. Differential expression analysis between grazing (Group G) and indoor-fed (Group HF) yaks revealed 157 differentially expressed lncRNAs (DElncs) (77 upregulated and 80 downregulated), 51 differentially expressed miRNAs (DEmiRs), and 1,003 differentially expressed mRNAs (DEMs). Functional enrichment analysis demonstrated that these differentially expressed transcripts were significantly enriched in energy metabolism and muscle development pathways, specifically AMPK, Insulin, and FoxO signaling. Based on these datasets, we constructed a muscle-specific ceRNA network. Notably, specific regulatory axes were identified, such as lncRNA TCONS_00010840 competing for miRNAs to regulate the expression of TRIM63, a key gene implicated in muscle atrophy and meat tenderness. CONCLUSIONS: Our findings suggest that intensive feeding modulates yak muscle growth and tenderness through IncRNA-mediated pathways involved in metabolic adaptation and extracellular matrix remodeling. The identified TCONS_00010840-miR - 30b - 5p- TRIM63 and TCONS_00013998-ADAMTS2 regulatory nodes represent potential molecular targets for improving yak meat quality. These results provide a theoretical framework for future functional studies into the molecular breeding of yaks.