Identification of Key Genes for Backfat Deposition in Dahe Pigs Based on Transcriptome Sequencing

Purpose To screen and identify the key candidate genes associated with backfat deposition of Dahe pigs.

Methods Based on transcriptome sequencing of the backfat tissues of 12 Dahe pigs, which six with high backfat thickness (HBF) and six with low backfat thickness (LBF), differentially expressed genes (DEGs) were screened, and their GO function and KEGG pathway enrichment were analyzed; and the key genes for backfat deposition of Dahe pigs were investigated combined with constructing protein-protein interaction (PPI) network. Three random selected key genes for backfat deposition were identified by RT-qPCR.

Results A total of 214 DEGs were identified, which 107 genes were up-regulated and 107 genes were down-regulated in HBF pigs. These DEGs were significantly enriched in GO terms such as oxoacid metabolic process, organic acid metabolic process, lipid metabolic process, carboxylic acid metabolic process, and pathways related to the regulation of fat deposition such as peroxisome proliferator-activated receptor (PPAR) signaling pathway, AMP-activated protein kinase (AMPK) signaling pathway, pyruvate metabolism, and tricarboxylic acid cycle pathway (P<0.01). Among these genes, six genes were identified as the key genes associated with backfat deposition, including PCK1, ME1, ACLY, ACACA, FASN and SCD. The expression levels of the random selected key genes, PCK1, ACLY and ME1 had significantly or extremely significantly differences in backfat tissues between HBF and LBF pigs (P<0.05 or P<0.01).

Conclusion The results preliminarily identify the key genes of backfat deposition in Dahe pigs, which provide a scientific foundation and basis for further revealing the molecular mechanism of pig backfat deposition in depth, and accelerating the genetic improvement of backfat related traits such as lean meat percentage.