Sequence Analysis Of Polymerase Activity Module In L Gene And G-L Intergenetic Region Of Rabies Virus

In this study, the cDNA fragments of polymerase activity module in L gene, G-L intergenic region (IGR) and L gene 5' terminal of three rabies virus strains in Guangxi were cloned and sequenced. The nucleotides sequence of these cDNA fragments mentioned above and their deduced amino acid sequence were compared with that of other rabies virus strains and rabies-related virus strains published previously. The result show that the homology of nucleotide sequence of polymerase activity module in L gene among three Guangxi rabies virus strains is 89.2%-90.3%, and their homology of deduced amino acid sequence is 99.0%-99.5%. Comparison of the sequence of nucleotide and amino acid of polymerase activity module of three Guangxi rabies virus strains with that of other fixed rabies virus strains and rabies-related virus strains, the nucleotide homologies between strains in Guangxi and fixed strains were 85.5% to 87.0%; and that of strains in Guangxi and rabies-related were 73.5% to 79.2%. Their homologies of deduced amino acid were ranged from 96.0% to 99.0% and 89.5% to 95.0%, respectively. In contrast with that of fixed strains and rabies-related strains, the amino acid on position 672, 681 and 745 of L protein in Guangxi strains were mutated to tryptophan, methionine and arginine respectively.The homology of nucleotide in G-L IGR among three Guangxi rabies virus strains was 70.8%-79.2%. The homology of nucleotide of Guangxi strains were 25.0% with that ofNishigahara strain and RC-HL strain, and 54.2%- 83.3% with other fixed rabies virus strains, and 16.7%-36.8% with rabies related virus strains, respectively. The length of IGR of rabies, which consisted of 24 nucleotides, was also different from the rabies related virus strains that contain 19 nucleotides, and Mokola strain contains 28 nucleotides. There was a different frequency of base between rabies virus and rabies related virus, too. The rabies virus contain rich adenine, and the rabies related virus contain rich cytosine.The homology of nucleotide and deduced amino acid in L gene 5' terminal among three Guangxi rabies virus strains was 87.6% to 88.4% and 91.6% to 96.5%, respectively. Comparison of the sequence of that in Guangxi rabies virus strains with that of some other fixed rabies virus strains and rabies related virus strains, the nucleotide homologies were between 82.8%-86.0% and 63.0% to 69.8%, homologies of deduced amino acid were ranged from 89.3.0% to 96.4% and 64.0% to 79.1%, respectively. The amino acids on position 30 to 45 of L protein were conserved, while the isoleucine on position 12 of L protein was changed to valine.The nucleotide sequence analysis showed that the genetic relationship among three Guangxi rabies virus strains was close. And it is a great difference between strains in Guangxi and fixed rabies virus strains and rabies-related strains.