# Screening and Functional Transformation Analysis of Genes Related to Skeletal Muscle Development in Supplemental-Fed Oula Sheep

## TL;DR

This study explores how genes and metabolic processes change during muscle development in Tibetan Oula sheep at different growth stages, identifying key genes and pathways that could help improve breeding practices.

## Contribution

The study identifies novel genes and signaling pathways involved in muscle development in Oula sheep under supplementary feeding.

## Key findings

- Metabolic processes related to energy and nutrient utilization are progressively enhanced with age in Oula sheep muscle.
- Genes like NDUFAB1 and pathways such as PI3K-AKT are potentially critical for regulating muscle development.
- Key genes including PTPRC, IL10, BUB1, and ITGB3 show significant roles in muscle growth across developmental stages.

## Abstract

To understand how muscle development changes with growth in Tibetan Oula sheep, we investigated the gene expression profiles in the longissimus dorsi muscle of female Oula sheep during the three-month fetal stage, six-month-old lamb stage, and eighteen-month-old adult stage using transcriptomic sequencing. Comparative analysis across these developmental stages revealed that metabolic processes related to energy and nutrient utilization were progressively enhanced with age. Furthermore, we identified several key genes, such as NDUFAB1, and signaling pathways, including the PI3K-AKT pathway, that are potentially critical in regulating muscle development. These findings provide deeper insights into the molecular mechanisms underlying muscle development in Oula sheep, offering valuable insights for future breeding strategies and management practices.

To investigate the gene regulatory mechanisms underlying muscle development in Oula sheep at different growth stages, under supplementary feeding, particularly the shift in core regulatory mechanisms governing muscle development from the fetal stage to the postnatal period, we conducted transcriptomic sequencing and comparative analysis of the longissimus dorsi muscle collected during the embryonic, lamb, and adult stages. Differentially expressed genes (DEGs) potentially associated with muscle growth and development were identified across various age phases. Furthermore, Short Time-series Expression Miner (STEM) analysis was employed to decipher the temporal expression patterns of these DEGs. The results indicated that metabolic processes related to carbohydrates, energy, and amino acids were enhanced with increasing age in Oula sheep muscle. Comparative analysis between different growth stages revealed that the functional enrichment of DEGs was directly associated with changes in skeletal muscle development, with significant enrichment in biological pathways such as ECM–receptor interaction, PI3K-AKT signaling pathway, and protein digestion and absorption. Additionally, we observed that PTPRC, IL10, NDUFAB1, BUB1, BUB1B, CDK1, ITGB3, and ITGB2 may play pivotal roles in the regulation of muscle growth and development across different stages in Oula sheep. These findings provide theoretical support for the understanding of the genetic regulatory mechanisms underlying muscle development in Oula sheep.