The Asia 2 specific signal peptide region and other domains in fusion protein genes characterized Asia 1 and Asia 2 canine distemper viruses

<p>Abstract</p> <p>Background</p> <p>Although the presence of Asia 2 group of canine distemper virus (CDV) was known by the sequencing and phylogenetic analysis of hemagglutinin (H) gene, the fusion (F) protein gene sequence of Asia 2 group had not been identified. So, the sequence analysis of F gene was carried out to elucidate the genotypic varaitons among Asian isolates.</p> <p>Results</p> <p>The phylogenetic analysis of F and H gene sequences from fourteen CDV isolates obtained from diseased dogs in Japan and Thailand indicated that the F genes had a new initiation codon and extra 27 nucleotides upstream of the usual open reading frame (ORF) and the F proteins had extra 9 amino acids at the N-terminal position only in Asia 2 isolates. On the contrary, the Asia 1 isolates had three extra putative N-glycosylation sites (two sites in the signal peptide region and one site in the F1 region) except for two strains of Th12 and Ac96I (two sites in signal peptide region) adding to four putative N-glycosylation sites that were conserved among all Asian isolates and Onderstepoort strain. In addition to this difference in N-glycosylation sites, the signal peptide region had a great diversity between Asia 1 and Asia 2 isolates. Also, characteristic amino acids were detected for some strains.</p> <p>Conclusion</p> <p>Asia 2 isolates were distinguished from other CDV lineages by the extra 27 nucleotide sequence. The signal peptide region of F gene gives a remarkable differentiation between Asia 1 and Asia 2 isolates. Strains Th12 and Ac96I were differentiated from other Asia 1 strains by the F protein glycosylation sites.</p

Propagation of Asian isolates of canine distemper virus (CDV) in hamster cell lines

<p>Abstract</p> <p>Backgrounds</p> <p>The aim of this study was to confirm the propagation of various canine distemper viruses (CDV) in hamster cell lines of HmLu and BHK, since only a little is known about the possibility of propagation of CDV in rodent cells irrespective of their epidemiological importance.</p> <p>Methods</p> <p>The growth of CDV in hamster cell lines was monitored by titration using Vero.dogSLAMtag (Vero-DST) cells that had been proven to be susceptible to almost all field isolates of CDV, with the preparations of cell-free and cell-associated virus from the cultures infected with recent Asian isolates of CDV (13 strains) and by observing the development of cytopathic effect (CPE) in infected cultures of hamster cell lines.</p> <p>Results</p> <p>Eleven of 13 strains grew in HmLu cells, and 12 of 13 strains grew in BHK cells with apparent CPE of cell fusion in the late stage of infection. Two strains and a strain of Asia 1 group could not grow in HmLu cells and BHK cells, respectively.</p> <p>Conclusion</p> <p>The present study demonstrates at the first time that hamster cell lines can propagate the majority of Asian field isolates of CDV. The usage of two hamster cell lines suggested to be useful to characterize the field isolates biologically.</p

The effect of bisulfite modification on the template activity of DNA for DNA polymerase I(1)

Cytosine residues of poly(C) and heat-denatured calf thymus DNA were transformed into 5,6-dihydrouracil-6-sulfonate (U(SO(−)(3))) residues by treatment with bisulfite. The poly(U(SO(−)(3))(2), C(3)) and poly(U(SO(−)(3))(9), C(1)) prepared did not form inter-base binding with either poly(A) or poly(I) as judged by the absence of hypochromicity in ultraviolet absorbance. U(SO(−)(3)) residues in the DNA inactivated it to serve as template for E.coli DNA polymerase I, while the template activity was restored by conversion of the U(SO(−)(3)) residues into U

Development of an Equine Herpesvirus Type 4-Specific Enzyme-Linked Immunosorbent Assay Using a B-Cell Epitope as an Antigen

The equine herpesvirus type 4 (EHV-4)-specific region of glycoprotein G has served as an antigen for serodiagnosis and seroepizootic studies of EHV-4 infection (B. S. Crabb and M. J. Studdert, J. Virol. 67:6332-6338, 1993; S. Yasunaga, K. Maeda, T. Matsumura, K. Kai, H. Iwata, and T. Inoue, J. Vet. Med. Sci. 60:1133-137, 1998; S. Yasunaga, K. Maeda, T. Matsumura, T. Kondo, and K. Kai, J. Vet. Med. Sci. 62:687-691, 2000). Here we identified a major B-cell epitope in the type-specific region of EHV-4 and applied it as an antigen in enzyme-linked immunosorbent assays (ELISAs). A 24-amino-acid repeat sequence expressed as a glutathione S-transferase fusion protein specifically reacted as well as the type-specific region with sera from foals infected with EHV-4. Five synthetic peptides (12-mer peptides) in the repeat sequence were included as ELISA antigens. The results indicated that the 12-mer peptide MKNNPIYSEGSL contained a major B-cell epitope specific for EHV-4 infection. Inclusion of this 12-mer peptide in ELISAs for an epidemiological study specifically detected EHV-4 infection in the field. These results indicated that the 12-mer epitope was responsible for the type-specific antibody response and therefore is useful for seroepizootic studies and serodiagnosis of EHV-4 infection