Characterizations Of Functional Genes In Porcine Epidemic Diarrhea Viruses Filed Samples In Fujian

The genetic characterizations of filed samples from Fujian Province, were investigated on the structural genes, i.e., S1, M, N, and ORF3by sequence and phylogenetic analysis. One neutralizing epitope in S gene was cloned and expressed by Prokaryotic system. The induced recombinant epitope was injected the rabbits to make polyclonal antiserum. The result in this study will be useful to the prevention and management of control of this disease.1. According to the results from sequence analysis, there were no significant deletions or insertions but some point mutations in the S1genes of the3filed samples. By contrast, unique point mutations were found in the ORF3region in both of P55and F422as well as an obvious deletion in P55. No special deletions or insertions but very few point mutations were found in the M and N gene of all the samples either.2. Due to the result from phylogenetic analysis among the3local filed samples and the reference strains, the diversity for the S1, ORF3, M and N gene was7.5,9.9,2.4, and3.7separately.3. The analysis of predicted characterizations of protein of S1showed that there were significant differences between the local samples and the reference strains in terms of the numbers of antigenic peptides and Maximum score position. Significant differences were also found in the analysis result of the PI, numbers of antigenic peptides and Maximum score position in ORF3. By contrast, no obvious differences were found in the M and N gene.4. The investigation on the ORF3genes from27local filed samples indicated that all the samples could be classified into2groups, one of which was composed of P55and5reference strains with the characteristic of a big deletion in nuclear and amino acid sequences. The other was comprised by3subgroups with all the local samples except P55. All the local samples had a long-distant relationship with the CV777, which was used in the development of vaccine.5. One neutralizing epitope in S genes of P718and P55, which were2local samples, were cloned and expressed by Prokaryotic system. The induced recombinant epitope mainly existed in precipitation in the form of inclusion body. The antiserum made from New Zealand White rabbits showed tilters of1:25600and1:51200for the P718and P55separately by ELISA analysis.