Studies On Cloning And Analysing Of MyoG Gene Exon 1 In Goose

To animals, the potential of meat production and the quality of meat is highly related to the idiosyncrasy of muscle tissue. The muscle fibrin of vertebrate has come into being in the period of embryo. And the quantity did not chang after birth. The growth of muscle mostly depended on the proliferation and differentiation of muscle cell. The proliferation and differentiation induced the increase of length and diameter in muscle fibrin. Yet it didn't lie on the hyperplasia of cell. Thus the quantity of muscle fibrin determines the meat production. The discovery of myogenic regulatory factors (MRFS) and the confirmation of its structure and function make people highly recognize the essence of muscle creation.Myogenin(MyoG) was one of MRFs which included MyoD,MyoG,Myf5 and MRF4. It could control the start of myoblasts fusion, and induce the myoblasts proliferation, and then turn the monocaryon myoblasts to the multinuclear myotubes. Thus MyoG had important function in MRFs. MyoG gene had three exons and two introns. And the sequence of exons had highly conservation.According to the method of Comparison Genomics and the sequence of chicken, a pair of primers were designed by Primer Premier 5.0 and Dnastar and the MyoG gene exon1 of goose were coloned (Genbank accession number: DQ294735).Sequence analysis suggested that the content of A, T, C and G in the exon 1 of goose MyoG gene were separately 19.2%, 34.0%, 32.3% and 14.6%. Exon1 coded 160 amino acids Thereinto the quantity of Cys which is related to the form of two sulfur bonds was 5 and they were located at 45, 63, 67, 72 and 75. Moreover the quantity and location were similar to chicken and turkey. By homology analysis, the nucleotide homology of MyoG gene exon1 between goose and chicken was 91.9%, and 89.6% between goose and turkey, with both 93.0% of amino acid homologies, which showed that some nucleotide mutations didn't cause the change of amino acid. The sites of different amino acids between goose and chicken were at 13^th,32^th,42^th,49^th,57^th,59^th,73^th,78^th,97^th and 139^th, the sites between goose and turkey at 13^th,29^th,42^th,49^th,57^th,59^th,73^th,78^th,97^th and 139^th.The homologies of 21 species in MyoG gene exon1 sequence had done with goose. The result showed that the homology between goose and chicken was 91.9% and the homology between goose and turkey was 89.6%. In addition, the homologies were 54%⁵7.5%, 53%⁶5%, 57%-65.5% between goose and amphibian, mammal, fish. All are lower than chicken and turkey. But the homologies among human, cattle, pig were about 90%. Among fish, the homologies between danio and zebrafish, fugu and tetra were 94.1% and 93.8% separately, but the homologies among other were lower.Aslo we analysed condon usage of amino acides coded by exon 1of MyoG gene in goose. The result suggested the usage frequence of Lue(11.88%),Glu(11.25%),Arg(12.5%),Ala(10%) and Pro(8.12%) were higher. The lower usage frequence of amino acids had Met, Trp and His and was only 0.62%. Others were 2.5%～6.3%. And the codon usage strategy were different among different amino acids in this region. Ala favors GCC and CGG., Arg likes CGC, His uses CAC, Leu uses CUG, Ser favors AGC, Val favors GUG, Thr favors ACC, and so on. This also showed the non-randomness of codon usage .The similarity analysis of codon usage between goose and other species suggested the codon usage of goose is different from other species. The similarity of codon usage between goose and chicken was 0.936. And 0.8～0.9 between goose and mammal such as human, cattle, pig, dog, and so on, both 0.75 between goose, mouse and goose, fugu, and 0.54～0.63 between goose and fish. Additional it were only 0.02～0.05 between goose and amphibian. These showed that different species had different codon usage.The analysis of the hidrophilicity, Surface probability, average charge of amino acids showed that the section of MyoG gene in goose had three high hidrophilicity regions. It located at 10^th～20^th, 80th¹00th and 140^th～150^th. The average charge of amino acids showed high density positive charge in the region of 80^th～100^th. And amino acids of the 80^th～100^th and 140^th～150^th region was exposure to the surface of MyoG protein. It showed that this region was perhaps the binding region of MyoG.