Alternative splicing dynamics in pig tissues under soybean oil supplementation

Lipid metabolism in pigs is a relevant model for understanding human metabolic regulation due to physiological similarities between the species. Alternative splicing (AS) generates transcript variants that can modulate metabolic pathways in the brain, liver, and skeletal muscle. This study aimed to identify and characterize AS events to explore the dynamics of AS under supplementation of soybean oil in these three tissues. We performed RNA sequencing in 36 pigs fed a soybean-corn diet supplemented with 1.5% or 3.0% soybean oil, using brain, liver, and muscle tissues. Expression matrices and structural annotation were generated for SUPPA analyses. Seven classes of splicing events were identified for each tissue, and only candidate genes exhibiting the highest differential proportion of spliced-in (DPSI) values were considered. Events were detected in both coding regions and 5' UTRs, indicating potential functional consequences. Differential splicing was present in FRMPD1 for brain, G6PC3 for liver, and MED1 and FBXL20 for muscle. These findings suggest that AS may regulate lipid metabolism and that coordinated splicing responses across tissues could also influence the metabolic adaptation and growth performance.