A Key Gene, PLIN1, Can Affect Porcine Intramuscular Fat Content Based on Transcriptome Analysis

Intramuscular fat (IMF) content is an important indicator for meat quality evaluation. However, the key genes and molecular regulatory mechanisms affecting IMF deposition remain unclear. In the present study, we identified 75 differentially expressed genes (DEGs) between the higher (H) and lower (L) IMF content of pigs using transcriptome analysis, of which 27 were upregulated and 48 were downregulated. Notably, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that the DEG perilipin-1 (PLIN1) was significantly enriched in the fat metabolism-related peroxisome proliferator-activated receptor (PPAR) signaling pathway. Furthermore, we determined the expression patterns and functional role of porcine PLIN1. Our results indicate that PLIN1 was highly expressed in porcine adipose tissue, and its expression level was significantly higher in the H IMF content group when compared with the L IMF content group, and expression was increased during adipocyte differentiation. Additionally, our results confirm that PLIN1 knockdown decreases the triglyceride (TG) level and lipid droplet (LD) size in porcine adipocytes. Overall, our data identify novel candidate genes affecting IMF content and provide new insight into PLIN1 in porcine IMF deposition and adipocyte differentiation.