Genetic structure and diversity of T cell receptor alpha chain genes in Hezuo minipig / 中国实验动物学报

ABSTRACT

Objective To analyze the complexity of molecular structure in porcine T cell receptor gene and its similarity compared to humans.Method Based on the gene of porcine T cell receptor alpha chain ( TCRα) from the Gen-Bank database, 93 swine T cell receptor alpha chain genes ( STA) were cloned by reverse transcription-polymerase chain reaction (RT-PCR) from porcine peripheral blood lymphocytes, lymph nodes and spleen.Result Sequence analysis showed that STA genes all contain a domain of variable signal peptide and V, hypervariable J and conservative C.Howev-er, nucleotide sequence of STA was not completely identical with only 68.4%to 98.7%homology among genes, and had extremely sophisticated polymorphism and diversity.This was accord with the genetic structure of TCRαchain.Molecular structure, genetic evolution and classification of these genes were carried out according to the homology of TCRαgene, which all have several sites and zones of mutation on the domain of signal peptide, FR1 and CDR1, FR2 and CDR2, FR3 and CDR3.Analysis of similarity and classification of TCRαV domain(STAV)and J domain (STAJ) of Hezuo minipig u-sing IMGT/V-QUEST tools compared with those of humans found the genetic evolution relationship that was closer, and each of TRAV and TRAJ also found to have a corresponding fragment of humans, ever in 92% of similarity of TRAV be-tween swine and humans.Conclusion Our results indicate that inbred Hezuo minipig possesses genetic diversity against complicated environment of microbes in healthy status, and Hezuo minipig is suitable as an animal model for research on human immunology and diseases.