Cloning And Sequence Analysis Of VP1 Gene Of Attenuated Viral Vaccine Strains Of Foot-and-Mouth Disease Virus Serotype O And A

Foot and mouth disease (FMD) is a highly contagious disease of cloven-hoofed animals. It is one of the most important animals infectious diseases. It is defined as A class animals infectious disease by OIE and Our Country . Many research data showed that VP1 gene contains major antigenic determinant of FMDV and is easy to be variable. This paper was studied on the cloning and sequence analysis of the VP1 gene of FMDV which were chose from different culture generations'strains on the basis of attenuated viral vaccines strains, named OE78, OE84, OR, OR10 of FMDV type O and AE105, AE123, AR5, AR15 of FMDV type A. VP1 genes were cloned and sequenced by routine technique of molecular biology. DNAstar software was used to study their genetics and variation according to the changes in the nucleotide sequences of VP1 gene. This work provided the basic information for further research in the aspects of vp1 gene genetics and variation of FMDV and for using attenuated viral vaccines strains to produce inactived vaccine.Compered all VP1 genes sequences with others VP1 sequences of FMDV from GenBank, the result indicated that the length of eight strains‵VP1 was 639bp. It was found that there was little difference among four strains of each type. Their hyomology among the strains of type O was 99.8%-100% in nucleotide sequences, and 98. 6%-98.9% for type A. But the difference was very distinct between four strains of type O and Akesu58 or O-A-58. Their homology was 80. 8%-87.2% in nucleotide sequences among these strains. For amino acid sequences, the differences were smaller than NT. The homology was 87. 8%-93.0% among them. There were distinct difference between four strains type A and XJ-KY-58, which homology was 94.6%-94.9% in nucleotide sequences among these strains. But because of a nucleotide inserted and deleted, its homology was 92.3%-93.0%. The homology was less than Nucleotide . There were some variation at the position of VP1 141-160 amino acids of FMDV type O attenuated by chick embryo, compared with epidemic strains from foreign countries around Xingjiang, the difference at amino acid site was 2 or 3. Compared with latest epidemic PanAsia strains, there were 3 amino acids variated. However, another antigen site at 200-213 amino acids was almost no change. Compared with foreign strains around Xingjiang, only one amino acid difference was found, and there was not difference with latest epidemic PanAsia strains. FMDV type A attenuated by chick embryo had high varitation at VP1 antigen site of 141-160 amino acids. Compared with f, There were 4 to 6 amino acids differed between foreign strains, but for another antigen site at 200-213 amino acids, there was only 0 or 1 amino...