Genomic organisation of a virulent Taiwanese strain of transmissible gastroenteritis virus

• Published in: Advances in experimental medicine and biology Vol. 342; p. 23
• Main Authors: Chen, C.M, Pocock, D.H, Britton, P
• Format: Journal Article
• Language: English
• Published: United States 1993
• Subjects: Amino Acid Sequence; AMINO ACID SEQUENCES; ANIMAL VIRUSES; Base Sequence; CLONE; CLONES; COMPLEMENTARY DNA; FENOTIPOS; GENE; GENES; Genome, Viral; Molecular Sequence Data; NUCLEOTIDE SEQUENCE; Open Reading Frames; PATHOGENICITY; PHENOTYPE; PHENOTYPES; PODER PATOGENO; Polymerase Chain Reaction; POUVOIR PATHOGENE; PROTEINAS; PROTEINE; PROTEINS; s gene; SECUENCIA NUCLEICA; SEQUENCE NUCLEIQUE; spike protein; Taiwan; TRANSMISSIBLE GASTROENTERITIS VIRUS; Transmissible gastroenteritis virus - genetics; Transmissible gastroenteritis virus - pathogenicity; VIRULENCE; VIRUS DE LOS ANIMALES; VIRUS DES ANIMAUX; VIRUS GASTROENTERITE DU PORC; VIRUS GASTROENTERITIS TRANSMISIBLE; Taiwan
• ISSN: 0065-2598

Transmissible gastroenteritis (TGE) infection causes 65% of infectious piglet diarrhoea in Taiwan. A virulent Taiwanese strain, TFI, of transmissible gastroenteritis virus (TGEV) from a field outbreak was isolated in cell culture and plaque purified. Phenotypic differences were observed in the ability of TFI to infect certain cell lines. TGEV strains TLM-83 (PRCV Belgium), TO-163 (TGEV Japan) and Purdue-115 (TGEV USA) infected both ST (swine testis) and RPTG (pig kidney) cell lines whereas TFI infected ST but not RPTG cells. To investigate this phenotypic variation cDNA was generated from TFI genomic and amplified by PCR with oligonucleotides derived from published TGEV sequence data. An 8.4kb cDNA derived from the 3'-end of the TFI genome was sequenced. Eight ORFs, corresponding to the three structural protein genes, four potential genes and the 3'-end of an incomplete ORF whose amino acid sequence corresponded to the carboxyl end of the 1b subunit of the polymerase gene, were identified on the TFI sequence. The overall sequence similarity of TFI with the other TGEV strains was over 97%. However, several deletions, insertions and point mutations were found on the TFI sequence when compared with other TGEV strains. The TFI S protein was found to contain 1449 amino acids, as also identified for the FS772/70 and Miller TGEV strains, but two amino acids longer than the Purdue S protein. The TFI ORF-3a gene encodes 72 amino acids, however, a 37 nucleotide deletion was found 16 nucleotides downstream of the TFI ORF-3a stop codon.