Genetic Polymorphisms Of AMPD1Gene And Its Correlation With IMP Content In Chicken

Flavor is one of the elements influncing the meat quality and inosine monophosphate acid (IMP) is one of the key components for meat flavor. Our study determined IMP content of the breast muscle from the Lingshan chickens and Fast Partridge using high performance liquid chromatography technology (HPLC). At the same time, we identified the single nucleotide polymorphisms (SNPs) of AMPD1gene which is one of the key genes in anabolic metabolism of IMP and analyzed the population genetic structure and the correlation with IMP of three SNPs. At last, we examined their expression in eleven tissues by real-time fluorescence quantitative PCR. The main results were as follows:1. Determination and analysis of the IMP content of breast muscleThe IMP content of breast muscle of the Lingshan chickens and Fast Partridge with a total number of116was determined using HPLC. The IMP content of Lingshan chickens was significantly higher than that of Fast Partridge(P<0.01) and the IMP content of the females was higher than that of the males for two breeds.2. SNPs scanning of5’UTR and coding region of AMPD1geneWe scanned SNPs of5’UTR and other fifteen exons of AMPD1gene from DNA pools by sequencing. Ten SNPs were found in Lingshan chickens and Fast Partridge and they were C-555A、T-350C、C-214G、G4064A、T5288C、A5573G、T6751C、G6805A、 C9228T and C9306T; The SNP T6751C in Exon8was missense mutation, resulting in the change of serine (Ser) to the Cysteine (Cys). The missense mutation altered slightly the physicochemical properties of AMPD1protein but did not change the secondary and space structure.3. Analysis of genetic polymorphisms of AMPD1gene and its correlation with IMP contentBy Bi-PASA and PCR-RLFP technology, we analyzed4064th、5573th and6805th of AMPD1gene and found that they were all purine conversion. Three genotypes were found in each site in the two breed. Polymorphic information contents of the three sites belonged to moderate polymorphism (0.25<PIC<0.5). Heterozygosity and effective number of alleles were not high, which suggested that they were genetically identical.The correlation between different genotypes of each SNP with the content of IMP showed that for G4064A, AA genotype has significantly higher IMP than GG genotype does (P<0.05), AG genotype is higher than GG genotype but they have no significant difference in Lingshan chickens; there is no significant difference in all genotypes in Fast Partridges; there is also no significant difference in all genotypes of different sexes in the two breeds. For A5573G, there is no significant difference in all genotypes in two breeds. For G6805A, AA genotype has significantly higher IMP content than AG genotype does(P <0.05), GG genotype is higher than AA genotype but they have no significant difference in Lingshan chickens; AG genotype has significantly higher IMP content than AA genotype does (P<0.05), GG genotype is higher than AG and AA genotype but they have no significant difference in Fast Partridges; GG genotype was not found and AA genotype has significantly higher IMP content than AG genotype does (P<0.05)in Lingshan male chickens, AA genotype has significantly higher IMP content than AG genotype does (P<0.05)but had no significant difference with GG in Lingshan female chickens; AG genotype has significantly higher IMP content than AA genotype does(P<0.05)in male Fast Partridges, GG genotype is higher than AG and AA genotypes but they have no significant difference in female Fast Partridges.4. Expression of AMPD1gene in different tissuesExpression pattern of AMPD1gene in the eleven tissues of the chickens were studied by real-time fluorescent quantitative PCR. The results showed that the highest expression levels were detected in abdominal fat and then in subcutaneous fat, breast muscle, leg muscle and liver; less in heart, kidney and gizzard; the lowest in glandular stomach, spleen and lung.