The Polymorphism In Coding Region Of Thrsp Gene And Its Association With Lipogenesis Capability In Pigs

Thyroid hormone responsive spot14(THRSP) is a nucleoprotein induced by thyroidhormone, which makes an essential effect on the regulation of animal lipogenesis. In orderto clarify the genetic mechanisms of the differences between Chinese native pig breeds(fat-type group, FTG) and introduced pig species (lean-type group, LTG) in carcass fatdeposition, we extracted DNA samples of ear tissues from FTG (n=228) composed ofWannan Spotted, Jixi Black and Dingyuan and LTG (n=92) from Landrace, Large White,Duroc and their hybrid pigs and then detected the SNPs in the coding region of thrsp gene.The effects of SNPs on mRNA folding and protein secondary structure in FTPG and LTPGwere predicted using Vienna RNA folding software and YASPIN web services, and theirdistribution and association with lipogenesis capability in FTG and LTG were analyzed.The results showed that the homologies of nucleotide sequence in coding region of pigthrsp gene with human and cattle were86%and88%, respectively. Two SNP sites, G123Aand A308G, were located at123bp and308bp away from the start of the CDS, respectively.The mutation at G123A site was a synonymous mutation, but the mutation at A308G sitecaused the change of amino acids from lysine to arginine at103th site of THRSP proteinwhich resulted in the changes of casein kinase â…¡ phosphorylation site from TKEE toTREE, mRNA folding and protein secondary structure. The frequencies of alleles123Gand308A were0.9759and0.5899in FTG, repectively, while that of alleles123G and308A were0.6577and0.8152in LTG. The total frequency of gamete123G308A and123G308G in FTG achieved above0.97, while that of gamete123A308A and123G308Ain LTG was0.8153. Data from the present study imply the association of polymorphism atG123A and A308G sites with lipogenesis capability of pigs and their important regulatingrole in the expression of lipogenesis genes in pigs.