Molecular Cloning, Expression And Genetic Variation Of AMPD1 Gene In Wild Boar And Swine

Adenosine monophosphate deaminase(AMPD)has only been found in all eukaryote. It is one of the key enzymes in the purine nucleotide cycle and catalyzes the deamination of AMP to IMP. AMPD is a complex allosteric enzyme encoded by a multigene family in mammals including AMPD1, AMPD2 and AMPD3. The AMPD1 gene is expressed predominantly in skeletal muscles. It is shown from research that AMPD1 was tightly linked with the NGFB gene. The porcine AMPD1 maps within known QTL with effects on carcass traits (carcass weight cold, shoulder meat weight, bacon meat weight, chops weight, head weight and muscle area). So AMPD1 may be regarded as a positional candidate for these traits. This study was designed to clone the cDNA of swine and wild boar AMPD1 gene based on the sequences of human, rat and mouse AMPD1 gene; to detect the polymorphisms by PCR-SSCP in five breeds of pigs; to investigate the expression characteristic of the gene by RT-PCR. The main results are as follows:1. The cDNA sequences of domestic pig and Wild boar AMPD1 gene were cloned in the first time by homologous cloning. The results showed that coding region of swine AMPD1 gene was composed of 2244 bp encoding 747 AA. The cDNA of AMPD1 gene in Wild boar was composed of 2240 bp and the open reading frame encodes 613 AA.2. 11 SNPs in exons of AMPD1 gene were found by PCR-SSCP method, and there were 4 missenses. Population genetics analyses showed that in each polymorphic locus, there was extremely significant difference among 5 breeds in the distribution of genotypes (P<0.01). While no significant difference was found between Wild boar and Min pig except the locus detected by primer S5.3. The expression characteristic of AMPD1 gene in heart, liver, stomach, kidney, spleen, lung, large intestine, small intestine, muscles and gonad tissue was investigated by RT-PCR in Wild boar and Yorkshire. The results showed that the pig AMPD1 gene was expressed only in skeletal muscle. And the expression of AMPD1 in muscle on different growing period in Yorkshire was analyzed. The expression level in muscle of Yorkshire was the most at the age of birth. There was barely expression at 6,9 and 12-month. Along with the increasing of age, the expression level showed a weakening trend.