Cloning, Polymorphism And Tissue Expression Profile Of GNMT And GLP-1R Gene In Swine

The combination of molecular marker-assisted selection(MAS) and traditional breeding metheds is one of the main methods of the swine genetic improvement engineering. As the basis of molecular MAS, fingding the major gene or molecular marker which contributed genetically much to the economic trait is very important With the development of genetic map,QTL mapping and functional genome research of human mouse and swine, we can use the information of QTL about important economic trait and choose new useful gene associated with the trait during the chromosome region which homologous to human and mouse. According to these theory, we studied the newest report of reseach improvement about comparision of homologous region between SSC7 and HSA6 in and abroad and the mapping information of swine QTL associated wi(?)h economic trait and found 2 genes in this region to do our research..The main results are (?)s follows:1. GNMT (Glycine-N-Methyltransferase):(1) GNMT is an key enzyme in amino acids (aa) metabolism of liver, and it was assigned at position 77 cM on SSC7 within a QTL region for fat traits (interval of 75-117 cM) and carcass lenth (79-126 cM) by S. Ponsuksili,2005.We obtained all five introns of GNMT used sequence homology at the basis of its known mRNA;(2) We found an L:T / M:G SNP at the 69bp in the first intron, developrd PCR-AsuC2 I-RFLP to detect this SNP during Large White and Meishan, and the allele frequencies were studied in these 2 breeds.In the 146 F₂ animals in the Large White×Meishan resouce family, the SNP was genotyped by the PCR- AsuC2 I-RFLP for carcass trait association analysis. We found that this SNP was significantly associated with MBW,psoas,ABWF,ABWL,PBWF,PBWL,FM(?),RLF, and was extremely significantly associated with ABW,PBW,ABWL,MBWL,PBWL,LMP.(3) The tissue expression profiles of GNMT was completed by semi-quantity RT-PCR. It was done during the 10 different tissues came from the same stage and breed. We Found that it was expressed highest in liver.2. GLP-1R (glucagon-like peptide-1 receptor)(1) GLP-1R can activate GLP-1 to stimulate the glucose-dependant insulin secretion,B- cell proliferation and the differentiation of new B-cells like insulin according to cAMP and P13K pathway. It was located on human chromosome 6p21. We studied the information about swine GLP-1R on NCBI and the homology between human and mouse and obtained part of its CDS, introns and 3'UTL.(2) We found an L:C / M:T SNP at the 272bp in the 10 intron, developed PCR- Eco130 I-RFLP to detect this SNP during Large White and Meishan, and the allele frequencies were studied in these 2 breeds. In the 135 F₂ animals in Large White×Meishan resouce family, the SNP was genotyped by PCR- Eco130 I-RFLP for carcass trait association analysis. We found that this SNP was significantly associated with LFW,CFW,BFT1,ABF,LEH,LEW,ABWF,MBWF and PBWF, and was extremely significantly associated withLC,FME(3) The tissue expression profiles of GLP-1R was completed by fluorescent quantitative RT-PCR. It was done during the 10 different tissues came from the same stage and breed.We found that it was expressed highest in kidney. Compared with human, it was especially expressed in swine fat.