Field isolates of transmissible gastroenteritis virus differ at the molecular level from the Miller and Purdue virulent and attenuated strains and from porcine respiratory coronaviruses.
The diversity in selected regions of the transmissible gastroenteritis virus (TGEV) and porcine respiratory coronavirus (PRCV) genomes was analyzed among known TGEV and PRCV strains and field isolates. The N-terminal half of the spike (S) glycoprotein gene and open reading frames (ORF) 3, 3-1 and 4 were amplified by reverse transcriptase reaction and polymerase chain reaction (RT/PCR), and analyzed using restriction fragment length polymorphism (RFLP) patterns of the amplified DNA. Reference TGEV strains (Miller and Purdue) and a PRCV strain (ISU-1), and TGEV and PRCV field isolates were analyzed. Based on the size of the ORF 3, 3-1 and 4 RT/PCR products, TGEV and PRCV strains could be quickly and easily differentiated into three groups designated TGEV Miller, Purdue types and PRCV. By RFLP analysis of the N-terminal region of the S glycoprotein gene and ORFs 3, 3-1 and 4, TGEV and PRCV strains were differentiated into five groups using the restriction enzyme Sau3AI. Sequence analysis of a PCR product in the ORFs 3, 3-1 and 4 from virulent and attenuated Miller strains demonstrated additional differences in that region which have been correlated with a change in virulence of TGEV isolates.
Kwon
H M
HM
Department of Veterinary Preventive Medicine, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster 44691, USA.
Saif
L J
LJ
Jackwood
D J
DJ
D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D018352:Coronavirus Infections / Q000662:veterinary* / Q000821:virology; D005761:Gastroenteritis, Transmissible, of Swine / Q000821:virology; D014644:Genetic Variation; D016679:Genome, Viral; D008297:Male; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D019318:Porcine Reproductive and Respiratory Syndrome / Q000821:virology; D019316:Porcine respiratory and reproductive syndrome virus / Q000235:genetics* / Q000302:isolation & purification; D017384:Sequence Deletion; D012689:Sequence Homology, Nucleic Acid; D013552:Swine; D013737:Testis / Q000166:cytology / Q000821:virology; D005760:Transmissible gastroenteritis virus / Q000235:genetics* / Q000302:isolation & purification