Characteristics of major structural protein coding gene and leader-body sequence in subgenomic mRNA of porcine reproductive and respiratory syndrome virus isolated in Japan.

Nucleotide sequence, 1713nt in length, of porcine reproductive and respiratory syndrome virus (PRRSV) isolated in Japan was determined. The sequence encompassed 3 overlapping open reading frames (ORFs), ORF5 to ORF7. These ORFs encodes major structural proteins of PRRSV. The deduced amino acid sequence of each ORF showed higher than 87.5% identity with an American isolate, and lower (54.6 to 80.5%) identity with an European isolate. This result supported a previous report about antigenic characteristics of the EDRD-1 strain. Leader-body junction sequence in subgenomic mRNA of the EDRD-1 strain was determined by sequencing cDNA clones of subgenomic RNAs. A common sequence motif of 5 nucleotide, represented by UA(A/G)CC, was identified as the junction sequence.