Molecular characterization, tissue expression profile, and SNP analysis of porcine SLC13A5

Solute carrier family 13 (sodium-dependent citrate transporter member 5, SLC13A5) gene has been recently found to play an important role in intramuscular fat content in pigs. In this study, the full-length cDNA of porcine SLC13A5 was obtained from the longissimus dorsi muscle of Shaziling pigs, using the rapid amplification of cDNA ends technique. Full-length porcine SLC13A5 cDNA was 2118 bp, with a 1665-bp open reading frame encoding 554 amino acids. The porcine SLC13A5 protein was analyzed using bioinformatic methodology, and found to include 18 potential phosphorylation sites (including six serine, nine threonine, and three tyrosine) and eight putative transmembrane domains. One single nucleotide polymorphism (SNP) site, A251G, was identified by polymerase chain reaction (PCR)-restriction fragment length polymorphism and the associations of this SNP with age at 100 kg and corrected back fat thickness were found to be not significant. Expression of SLC13A5 was evaluated in ten tissues from 25-day-old full-sib Yorkshire and Shaziling piglets (both N = 3), using quantitative PCR analysis. Expression levels of SLC13A5 differed significantly between the breeds in cecum, liver and crureus muscle. In each breed, gene expression levels were significantly different in longissimus dorsi muscle, compared to the nine other tissues. This study has laid the foundation for further investigations of the molecular mechanisms of SLC13A5 in pigs.