Characterization of pig skeletal muscle transcriptomes in response to low temperature

The response of mammals to cold environment is a complex physiological activity, and its underlying mechanism must be analyzed from multiple perspectives. Skeletal muscle is an important thermogenic tissue that maintains body temperature in mammals. We dissected the molecular mechanism of pig skeletal muscle response to a cold environment by performing comparative transcriptome analysis in the Enshi black pig.Three pigs were subjected to acute cold stress (3 days), three pigs were subjected to cold acclimation (58 days), and three pigs were used as controls. RNA-seq was used to screen the differentially expressed genes (DEGs) of skeletal muscle.Using RNA-seq methods, we identified 1241 DEGs within the acute cold stress group and 1886 DEGs within the cold acclimation group. Prolonged cold exposure induced more gene expression changes. A total of 540 key cold-responsive DEGs were found, and their trends were consistent within the acute cold stress group and cold acclimation group. Gene expression pattern analysis showed that there were significant differences between the low-temperature treatment groups and the control group, and there were also differences between individuals after long-term low-temperature treatment. Analysis of DEGs revealed that 134 pathways were significantly enriched in the cold adaptation group, 98 pathways were significantly enriched in the acute cold stress group, and 71 pathways were shared between the two groups. The 71 shared pathways were mainly related to lipid, amino acid, and carbohydrate metabolism; signal transduction; endocrine, immune, and nervous system; cardiovascular disease; infectious diseases caused by bacteria or viruses; and neurodegenerative disease.In conclusion, this study provides insights into the molecular mechanism of porcine skeletal muscle response under low-temperature environment. The data may assist further research on the mechanism of pig response to cold exposure.