title: Characterization of the cytopathic BVDV strains isolated from 13 mucosal disease cases arising in a cattle herd.
abstract: Bovine viral diarrhea virus (BVDV) is a positive single stranded RNA virus belonging to the Pestivirus genus of the Flaviviridae family. BVDV has a wide host range that includes most ruminants. Noncytopathic (ncp) BVDV may establish lifelong persistent infections in calves following infection of the fetus between 40 and 120 days of gestation. Cytopathic (cp) BVDV strains arise from ncp strains via mutations. The most common cp mutations are insertions of RNA derived from either host or a duplication of viral sequences into the region of the genome coding for the NS2/3 protein. Superinfection of a persistently infected animal with a cp virus can give rise to mucosal disease, a condition that is invariably fatal. A herd of 136 bred 3-year old cows was studied. These cows gave birth to 41 PI animals of which 23 succumbed to mucosal disease. In this study, we characterized the ncp and cp viruses isolated from 13 of these animals. All viruses belonged to the BVDV type 2a genotype and were highly similar. All the cp viruses contained an insertion in the NS2/3 coding region consisting of the sequences derived from the transcript encoding a DnaJ protein named Jiv90. Comparison of the inserted DnaJ regions along with the flanking viral sequences in the insertion 3' end of the 13 cp isolates revealed sequence identities ranging from 96% to 99% with common borders. This suggested that one animal likely developed a cp virus that then progressively spread to the other 12 animals. Interestingly, when the inserted mammalian gene replicated within viral genome, it showed conservation of the same conserved motifs between the different species, which may indicate a role for these motifs in the insertion function within the virus genome. This is the first characterization of multiple cp bovine viral diarrhea virus isolates that spread in a herd under natural conditions.
authors.affiliation: Department of Veterinary and Biomedical Sciences, SDSU, Brookings, SD 570076, USA. Electronic address: Mahmoud_f_darweesh@yahoo.com.
authors.forename: Mahmoud F
authors.initials: MF
authors.lastname: Darweesh
authors.affiliation: Department of Veterinary and Biomedical Sciences, SDSU, Brookings, SD 570076, USA. Electronic address: mrigendra@medgenelabs.com.
authors.forename: Mrigendra K S
authors.initials: MK
authors.lastname: Rajput
authors.affiliation: Department of Veterinary and Biomedical Sciences, SDSU, Brookings, SD 570076, USA. Electronic address: lyle.braun@sdstate.edu.
authors.forename: Lyle J
authors.initials: LJ
authors.lastname: Braun
authors.affiliation: Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, IA 50010, USA. Electronic address: Julia.Ridpath@ARS.USDA.GOV.
authors.forename: Julia F
authors.initials: JF
authors.lastname: Ridpath
authors.affiliation: Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, IA 50010, USA. Electronic address: John.Neill@ARS.USDA.GOV.
authors.forename: John D
authors.initials: JD
authors.lastname: Neill
authors.affiliation: Department of Veterinary and Biomedical Sciences, SDSU, Brookings, SD 570076, USA. Electronic address: christopher.chase@sdstate.edu.
authors.forename: Christopher C L
authors.initials: CC
authors.lastname: Chase
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000635:transmission / Q000821:virology*; D002417:Cattle; D003588:Cytopathogenic Effect, Viral; D001908:Diarrhea Viruses, Bovine Viral / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity; D014644:Genetic Variation; D005838:Genotype; D054884:Host-Pathogen Interactions; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D012367:RNA, Viral / Q000235:genetics; D011995:Recombination, Genetic
chemical_list: D012367:RNA, Viral
keywords: Bovine viral diarrhea virus; Cytopathogenicity; DnaJ; Insertion; Mucosal disease; RNA recombination