Shandong Province, Local Chicken Flavor Characteristics Of Candidate Genes Adsl With Atic Research

China is one of the most abundant countries in resource of poultry's hereditary. Chinese native chicken breeds are famous for their tender and flavor. The germplasm resources of Shandong native chicken breeds are important components of livestock and poultry of our country. The genetic polymorphism of these livestock and poultry breeds is the hereditary foundation on vareital improvement in the future. In livestock and poultry's meat products, sodium glutamate salt and inosinic acid are main delicious flavor things. At present, more and more countries use IMP (inosine monophosphate) content as the criterion of meat flavor and freshness.The meat quality of livestock and poultry is a quantitative trait and some quantitative trait loci (QTLs) which have greater effects are major genes. Therefore, the study on these major genes and QTLs can accelerate the study of chicken heredity which is difficult to improve by the traditional breeding methods. All potential genes affecting the production and content of inosinic acid (IMP) are candidate genes influencing the meat flavor characteristic. This research studied ADSL and ATIC genes as candidate genes controlling chicken's flavor characteristic trait. ADSL and ATIC catalyze the last three step responses in the de novo purine biosynthetic pathway. By analysing the difference of activation of the enzymes in de novo purine synthesis and purine nucleotide recycling, we expect to find the basic reason of different inosinic acid content in different chicken breeds, and to offer the basis for molecular marker assist selection to chicken's meat flavor characteristic trait.Adenylosuccinate lyase (ADSL) is a bifunctional enzyme catalyzing de novo purine synthesis and purine nucleotide recycling. ADSL is an important enzyme in purine biosynthesis pathway and regulates the cellular metabolism by controlling both intermediates of Krebs cycle in eukaryote. There are two amino acid variation caused by two missense mutations might have certain influence on the activity of ADSL in Jining Hundred chicken. The C114R amino acid variationcaused by the point mutation T340C lies in domain 1 which is one of the three conserved regions in fumarase superfamily. C114R amino acid variation is close to the residue His 108 played a role in binding the AMP portion of substrate, which may influence the binding of AMP and ADSL. The K296R amino acid variation caused by the point mutation A887G lies in the signature motif of fumarase superfamily.The motif implicate as potentially interacting with carboxylate groups in both of the alternative substrates SAICAR and adenylosuccinate. So, K296R amino acid variation will certainly influence the activation of the chicken ADSL.What deserves to be mentioned is a single nucleotide mutation C-27T in 5'UTR found in all individuals of Shouguang chicken. The C-27T mutation malces CTCC which is non-potential binding site for NRF-2 (nuclear respiratory factor 2) mutate to CTTC for binding site NRF-2. Contrary to this exactly, Marie considered a point mutation (CTTC â†'CTCC) in the first binding site for NRF-2 in human, which might be a frequent cause of human ADSL deficiency. So we think the two potential binding sites for NRF-2 may play an important role in the regulation of purine biosynthesis.ATIC possesses both of 5-aminoimidazole-4-carboxamide-ribonucleotide transformlase (AICARTfase) and inosine monophosphate cyclehydrolase (IMPCH) activities. ATIC catalyze the penultimate and final steps in the de novo purine biosynthetic nucleotide pathway. There are 11 mutations in ATIC gene altogether, 7 among them take place in encoding region and 5 are missense mutation. Amino acid varition M211T and D540G in Langya chicken lie in near the active site residues involved in binding AICAR and folate including Arg208, Tyr209, Phe542, Asp547. They may influence AICARTfase activation by controlling the binding of AICARTfase and both substrates.There are two bases mutation in 5' flanking region which may influence the activity of ATIC. An insert of -1035T make a potential binding site for Oct-1 (octamer-binding protein 1) mutate to a potential binding site for CdxA.The...