title: Characterisation of a recent virulent transmissible gastroenteritis virus from Britain with a deleted ORF 3a.
abstract: Analyses of transmissible gastroenteritis virus (TGEV) and porcine respiratory coronavirus (PRCV) isolates have suggested that tropism and pathogenicity are influenced by the spike protein and ORF 3. In general, enteric viruses (TGEV) have been shown to contain intact spike and ORF 3 genes, whilst respiratory isolates (PRCV) have major deletions within both regions. Virulence has been correlated to a functional ORF 3. Here, sequence analysis of a recent isolate of virulent TGEV, revealed a variant with an intact spike gene, but a large deletion in ORF 3a. This suggests that ORF 3a is not essential for enteric virulence.
authors.affiliation: Virology Department, Veterinary Laboratories Agency, Addlestone, Surrey, U.K.
authors.forename: A
authors.initials: A
authors.lastname: McGoldrick
authors.forename: J P
authors.initials: JP
authors.lastname: Lowings
authors.forename: D J
authors.initials: DJ
authors.lastname: Paton
mesh_terms: D000818:Animals; D001483:Base Sequence; D017934:Coronavirus / Q000145:classification / Q000235:genetics*; D017931:DNA Primers; D005761:Gastroenteritis, Transmissible, of Swine / Q000635:transmission; D014644:Genetic Variation; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017384:Sequence Deletion; D064370:Spike Glycoprotein, Coronavirus; D013552:Swine; D005760:Transmissible gastroenteritis virus / Q000235:genetics* / Q000472:pathogenicity* / Q000502:physiology; D006113:United Kingdom; D014759:Viral Envelope Proteins / Q000235:genetics* / Q000378:metabolism; D014774:Virulence
chemical_list: D017931:DNA Primers; D008562:Membrane Glycoproteins; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins