title: Cloning, sequencing and expression of the S protein gene from two geographically distinct strains of canine coronavirus.
abstract: The gene encoding the spike (S) protein from two geographically distinct strains (American and British) of canine coronavirus (CCV) was cloned and sequenced. The nucleotide sequence revealed open reading frames of 1443 or 1453 amino acids, respectively. Structural features include an N-terminal hydrophobic signal sequence, a hydrophilic cysteine-rich cluster near the C-terminus, two heptad repeats and 29 or 33 potential N-glycosylation sites. Pairwise comparisons of S amino acid sequences from these isolates with other CCV strains (Insavc1 and K378) revealed that heterogeneity, found mostly in the form of conservative substitutions, is distributed throughout the canine sequences. However, 5 variable regions could be identified. Similar analysis with feline, porcine, murine, chicken and human coronavirus sequences revealed that the canine sequences are much more closely related to the feline S protein sequence than to the porcine S protein sequences even though they are all from the same antigenic group. Moreover, the sequence similarity between CCV isolates and the feline coronavirus, feline infectious peritonitis virus (FIPV) was comparable. Expression of the CCV or the transmissible gastroenteritis virus (TGEV) S gene using the vaccinia virus system produced a protein of the expected size which could induce extensive syncytia formation in infected canine A72 cells.
authors.affiliation: Department of Pathology, University of Cambridge, UK.
authors.forename: B C
authors.initials: BC
authors.lastname: Horsburgh
authors.forename: T D
authors.initials: TD
authors.lastname: Brown
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002415:Cats; D002478:Cells, Cultured; D002645:Chickens; D003001:Cloning, Molecular / Q000379:methods; D017939:Coronavirus, Canine / Q000235:genetics*; D004285:Dogs; D015870:Gene Expression; D005814:Genes, Viral; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000096:biosynthesis; D016415:Sequence Alignment; D017421:Sequence Analysis; D064370:Spike Glycoprotein, Coronavirus; D013552:Swine; D014162:Transfection; D014759:Viral Envelope Proteins / Q000235:genetics*; D014764:Viral Proteins / Q000096:biosynthesis / Q000235:genetics
chemical_list: D008562:Membrane Glycoproteins; D011994:Recombinant Proteins; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins; D014764:Viral Proteins; C578557:spike glycoprotein, SARS-CoV; C578553:spike protein, mouse hepatitis virus