Research On Structure, Function, Expression And Molecular Biology Typing Of SLA-DQ And DR Genes

Research on Structure, Function, Expression of SLA-DQ and DR Genes and Molecular Biology Typing of SLA-DRB geneSUMMARYThe MHC genes of swine play an important role in response and regulation of immune.In the course of production and breeding of animals,researches on MHC genes of swine should promote the breeding of disease resistance.In this article,the DQ and DR genes ,as the part of SLA-II genes,will be studied deeply by its structures , functions and mRNA changes in different stages. In order to study the relations between the SLA class II genes and disease resistance,the technology of molecular biology typing available on practice will be studied.1. Research and analysis of structure and function of SLA-DQA, DQB, DRA and DRB genesTotal RNA was isolated from peripheral blood lymphocytes of Wuzhishan and Erhualian pigs using the Tripure Isolation Reagent, then, RT-PCR was performed to proliferate SLA -DQA,DQB,DRA and DRB genes and the products were sequenced by cloning method. All 8 complete cDNA sequences were presented, the numbers of nucleotide of SLA-DQA,DQB,DRA and DRB cDNA were 768,786,759 and 801 bp .respectively.The clone XX-591C4 (Accession Number: BX088590) was blasted out by the four cDNA sequences from the molecular databases in GenBank. The cDNA sequences of four genes were analyzed by comparing the sequence of clone XX-591C4 ,which calculated by the programme Sim4 at the http://pbil.univ-lyonl .fr/ web. Four complete DNA sequences were obtained, the numbers of nucleotide of SLA-DQA,DQB,DRA and DRB genomic DNA were 5122,8010,4159 and 12237 bp .respectively.The sequences of cDNA and genomic DNA of DQA,DQB,DRA and DRB genes were submitted and entried the GenBank. Their accession number were AY243100, AY243101, AY243102, AY243103, AY243104, AY243105, AY243106, AY243107 and AY303988, AY303989, AY303990, AY303991,respectively.Of the four genes,DRA gene was very conservative, DRB gene was more polymorphic, the characteristics of DQA and DQB genes were between the DRA gene and DRB gene and very near ,by analyzing the cDNA sequences and predicted peptide chains.Sequence comparison with those of known Haplotype C and D Miniature Swine inGenBank by the softwares of Primer Premier 5.0 and GeneDoc showed that:1. In the predicted amino acid sequence of DQA, 23 amino acid residues from 1 to 23 formed the domain of signal peptide, similarly the al functional domain was 87 residues from 24 to 110 , the