TY - JOUR
T1 - Porcine reproductive and respiratory syndrome virus comparison
T2 - Divergent evolution on two continents
AU - Nelsen, Chris J.
AU - Murtaugh, Michael P
AU - Faaberg, Kay S.
PY - 1999
Y1 - 1999
N2 - Porcine reproductive and respiratory syndrome virus (PRRSV) is a recently described arterivirus responsible for disease in swine worldwide. Comparative sequence analysis of 3'-terminal structural genes of the single- stranded RNA vital genome revealed the presence of two genotypic classes of PRRSV, represented by the prototype North American and European strains, VR- 2332 and Lelystad virus (LV), respectively. To better understand the evolution and pathogenicity of PRRSV, we obtained the 12,066-base 5'-terminal nucleotide sequence of VR-2332, encoding the viral replication activities, and compared it to those of LV and other arteriviruses. VR-2332 and LV differ markedly in the 5' leader and sections of the open reading frame (ORF) 1a region. The ORF 1b sequence was nearly colinear but varied in similarity of proteins encoded in identified regions. Furthermore, molecular and biochemical analysis of subgenomic mRNA (sgmRNA) processing revealed extensive variation in the number of sgmRNAs which may be generated during infection and in the lengths of noncoding sequence between leader-body junctions and the translation-initiating codon AUG. In addition, VR-2332 and LV select different leader-body junction sites from a pool of similar candidate sites to produce sgmRNA7, encoding the viral nucleocapsid protein. The presence of substantial variations across the entire genome and in sgmRNA processing indicates that PRRSV has evolved independently on separate continents. The near-simultaneous global emergence of a new swine disease caused by divergently evolved viruses suggests that changes in swine husbandry and management may have contributed to the emergence of PRRS.
AB - Porcine reproductive and respiratory syndrome virus (PRRSV) is a recently described arterivirus responsible for disease in swine worldwide. Comparative sequence analysis of 3'-terminal structural genes of the single- stranded RNA vital genome revealed the presence of two genotypic classes of PRRSV, represented by the prototype North American and European strains, VR- 2332 and Lelystad virus (LV), respectively. To better understand the evolution and pathogenicity of PRRSV, we obtained the 12,066-base 5'-terminal nucleotide sequence of VR-2332, encoding the viral replication activities, and compared it to those of LV and other arteriviruses. VR-2332 and LV differ markedly in the 5' leader and sections of the open reading frame (ORF) 1a region. The ORF 1b sequence was nearly colinear but varied in similarity of proteins encoded in identified regions. Furthermore, molecular and biochemical analysis of subgenomic mRNA (sgmRNA) processing revealed extensive variation in the number of sgmRNAs which may be generated during infection and in the lengths of noncoding sequence between leader-body junctions and the translation-initiating codon AUG. In addition, VR-2332 and LV select different leader-body junction sites from a pool of similar candidate sites to produce sgmRNA7, encoding the viral nucleocapsid protein. The presence of substantial variations across the entire genome and in sgmRNA processing indicates that PRRSV has evolved independently on separate continents. The near-simultaneous global emergence of a new swine disease caused by divergently evolved viruses suggests that changes in swine husbandry and management may have contributed to the emergence of PRRS.
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U2 - 10.1128/jvi.73.1.270-280.1999
DO - 10.1128/jvi.73.1.270-280.1999
M3 - Article
C2 - 9847330
AN - SCOPUS:0032889516
SN - 0022-538X
VL - 73
SP - 270
EP - 280
JO - Journal of virology
JF - Journal of virology
IS - 1
ER -