Characterization of Genes Related to Intramuscular Fat Deposition in Muscles of Piglets Under Cold Exposure by Whole Transcriptome Sequencing

Background/Objectives: Understanding the regulatory mechanisms of intramuscular fat accumulation is crucial for maintaining skeletal muscle function and treating muscle-related diseases. It is known that cold exposure can lead to fat deposition in the muscles of mice and pigs. However, so far, there is very limited knowledge about the factors influencing its formation under cold exposure conditions. This study used piglets as an animal model to investigate intramuscular fat accumulation under cold exposure. Methods: Six piglets were exposed to 10 °C, and six piglets were exposed to 25 °C. A whole transcriptome joint analysis was performed on the longissimus dorsi muscle of three piglets randomly selected from each group. Results: No fever or cough symptoms were observed in all experimental groups, and the cold exposure vs. control groups’ RNA data were compared. The study identified 705 differentially expressed messenger RNAs, 87 long non-coding RNAs, 57 microRNAs, and 236 circular RNAs. CD36 Molecule (CD36 Blood Group) (CD36) was upregulated, while adiponectin (ADIPOQ) was downregulated. Conclusion: We established a competing endogenous RNA network centered around CD36, Protein Phosphatase 1 Regulatory Subunit 3G (PPP1R3G) and ADIPOQ for intramuscular fat accumulation by using a pig model exposed to a cold temperature. This study provides important references for further understanding the regulatory mechanism of intramuscular fat.