title: The S gene of canine coronavirus, strain UCD-1, is more closely related to the S gene of transmissible gastroenteritis virus than to that of feline infectious peritonitis virus.
abstract: To gain insight into the genetic relationships among six canine coronavirus (CCV) strains, the variable region of the spike (S) protein gene was sequenced. The CCV strains were: two ATCC reference strains, the Insavc-1 vaccine strain, the National Veterinary Services Laboratories (Ames, IA) challenge strain, and two California field isolates (UCD-1 and UCD-2) from the 1970s. All six strains, downstream of the nucleocapsid (N) protein gene, had sufficient size for an ORF 7b, and thus, none were transmissible gastroenteritis virus (TGEV)-like since TGEV lacks ORF 7b. By sequence analysis of the variable domain at the 5' end of the S gene, five of the six CCV strains had a high degree of identity with feline infectious peritonitis virus (FIPV). However, one CCV field isolate (UCD-1) was different and had a high degree of identity with the 5' end of the TGEV S gene. This suggests that RNA recombination occurred at this site between antigenically related coronaviruses. The low passage field isolates, UCD-1 and UCD-2, varied in their initial infectivity for swine testicular cells suggesting that sequence differences in the variable domain of the S gene may account for biological variation among CCVs.
authors.affiliation: Virology Swine Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, IA 50010, USA.
authors.forename: R D
authors.initials: RD
authors.lastname: Wesley
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000956:Antigens, Viral / Q000235:genetics*; D002415:Cats; D002478:Cells, Cultured; D017939:Coronavirus, Canine / Q000145:classification / Q000235:genetics* / Q000276:immunology; D016765:Coronavirus, Feline / Q000145:classification / Q000235:genetics / Q000276:immunology; D004285:Dogs; D005455:Fluorescent Antibody Technique; D008969:Molecular Sequence Data; D010802:Phylogeny; D012328:RNA Viruses / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017421:Sequence Analysis; D005760:Transmissible gastroenteritis virus / Q000145:classification / Q000235:genetics / Q000276:immunology; D014764:Viral Proteins / Q000235:genetics*
chemical_list: D000956:Antigens, Viral; D014764:Viral Proteins; C064484:spike protein S, Transmissible gastroenteritis virus