Study On The E₂ Gene Nucleotide Sequences Of CSFV Field Strains And Some Characteristics Of Its Multiplication In PK15 Cells

The major protechve anhgen endoding regions Of fy genes of Field Isolates ofCSFV frOm five countries were amPlified by RT-PCR and Nest-PCR. Then theywere cloned and sequenced. ComParison and analysis of th6 nucleotide sequencesand the deduced ndno sequences among the stfains from fferent sopoe withCSFV C-strain were perfOrmed by comPuter with the GoldKey software. ThefUAner study of the two strains genetic relationship was done by the phylogenetictrbo consmicted on the base of analyzing the data of the E2 gene with computersoftware. The results showed some substitutions of nucleotide or deduced andnoacid scattering along the fy genes or their encoding proteins with the homology ofthe nucleotide and aInino acid sequences being 8l.7~83.1% and 87.3~88.6%,indicating the five strains had varied genetically to a cendn extent, they wereclassifled into the same subgroups in the phylogenehc tree, and the homologybetWeen the five strains and CSFV strain C were lower, so they belonged intodifferent subgrOups.Meanwhile, In this rePort, some characterishcs of the mulhplication of CSFVLT strain were studied by means of the inununofluorescence technique. Thelocation of CSFV's replication in PKl5 cell is detected by the multiclonedantibodies of CSFV Fluorescened intensity with time prolorged was fUrtherstudied, It was found that the special fluorescence becarne brighter and brighteruntile 54 hour after infected. But following it,the fluorescence intensity weakrand weakee the morphic aPpearance of PK,, cell turned into thegularity and eventhere aPPeared some vacuoles in cell plasma.