Abstract：Platelet-derived growth factor receptor (PDGFRα) is the member of tyrosine kinase receptor family and has a potential role of regulating lipid metabolism. The aim of this study was to clone cDNA of PDGFRα and analyze its mRNA expression level in different tissues and different periods of pig (Sus scrofa). The specific primers were designed based on the published nucleotide sequence of human (Homo sapiens), bovine (Bos taurus) and mouse (Mus musculus) in GenBank, and the whole cDNA of porcine PDGFRα gene was cloned using RT-PCR and RACE. The cloned full-length cDNA of PDGFRα gene was 6 360 bp (GenBank accession: KP329568) containing an open reading frame (ORF) of 3 270 bp, 2 964 bp 3' untranslated regions (UTR), 126 bp 5'UTR, encoding a protein of 1 089 amino acid. This gene spaned approximately 148 Mb on the genome, and contained 23 exons and 22 introns. The homology analysis of porcine PDGFRα gene indicated that the nucleotides and amino acids had high similarity with human, bovine, sheep (Ovis aries) and mouse. Ten N-glycosylation sites and 75 phosphorylation sites were predicted in the translated PDGFRα protein, as well as one signal peptide. The protein structure analysis showed that PDGFRα protein had 2 transmembrane helices. The N-terminal of the PDGFR protein was high hydrophobic, but the C-terminal showed high hydrophilism. Quantitative Real-time PCR (qRT-PCR) results suggested that PDGFRα mRNA expressed in heart, liver, spleen, lung, kidney, small intestine and skeletal muscle. PDGFRα mRNA expressed abundantly in spleen, followed by kidney and lung. Six kinds of muscle, including soleus muscle, supraspinatus muscle, biceps femoris muscle, psoas minor muscle, gastrocnemius muscle and loin muscle, were selected. The qRT-PCR results showed that the expression of slow muscles represented with soleus muscle was extremely higher than that in fast muscles represented with loin muscle (P＜0.01). Different growth stages expression analysis showed that expression of porcine PDGFRα gene was extremely higher in the primary stage than that in weaning and adult stage (P＜0.01). In conclusion, the research obtained the full-length cDNA of porcine PDGFRα gene, the rule of tissue expression and relative mRNA expression of PDGFRα gene in different muscles. The results provide a basic data for further understanding of the function of PDGFRα gene.
