Comparison of expression levels of fourteen genes involved in the lipid and energy metabolism in two pig breeds

Fat content, fatty acid composition and lean cut weight are important parameters which influence meat and carcass quality in pigs. Up to now, the genes involved in the regulation of the lipid and energy metabolism in porcine skeletal muscle and fat tissue are still relatively unknown. The aim of this study was to investigate the expression levels of fourteen genes (ACACA, ACLY, CES3, ENO3, FASN, INSIG2, LMNA, MTTP, ACVR1C, NAMPT, PLIN1, PLIN2, PLTP and SORT1) mapped on different chromosomes (1, 4, 7, 8, 9, 12, 15 and 17) which were chosen for their involvement in lipid or energy metabolism in porcine muscle and backfat tissue. Tissue samples from Italian Large White and Italian Duroc pig breeds were collected at the slaughterhouse and frozen in liquid nitrogen. After extraction, the mRNA was quantified by quantitative real time polymerase chain reaction (RT-PCR) and the transcription levels of the genes analysed were compared between breeds for each tissue. In the backfat tissue, differences were found for the ACACA, ACLY, and FASN genes whose highest gene expression levels were found in Italian Large White pigs. In addition, a correlation analysis was carried out between the transcription levels of the genes considered in each tissue and breed. Co-expression relationships still relatively unknown were identified, suggesting new associations between genes which in some cases differed between the two breeds. These results suggest differences between Italian Large White and Italian Duroc pig breeds determined at the genome level affecting carcass quality and fat traits.