Analysis of the fusion protein gene of the porcine rubulavirus LPMV: comparative analysis of paramyxovirus F proteins

Complementary DNA clones representing the fusion (F) protein gene of the porcine rubulavirus LPMV were isolated and sequenced. The F gene was found to be 1,845 nucleotides long containing one long open reading frame capable of encoding a protein of 541 amino acids. The cleavage motif for F0 into F1 and F2 is His-Arg-Lys-Lys-Arg. A sequence comparison and a phylogenetic analysis was performed in order to identify possible functional domains of paramyxovirus fusion proteins and also to classify the porcine rubulavirus. The F gene of LPMV is most closely related to the human mumps virus and simian virus type 5 F genes, and is therefore classified into the rubulavirus genus. A coding region for a small hydrophobic protein was however not found between the F and hemagglutinin-neuraminidase (HN) genes as previously found in both SV5 and mumps.

The molecular biology of the porcine paramyxovirus LPMV

Protein and genomic studies of a previously uncharacterized porcine paramyxovirus (designated LPMV) confirmed that it was a member of the paramyxovirus genus. The nucleotide sequences and deduced amino acids of the complete P-gene, M-gene, F-gene and HN-gene as well as the intergenic sequences have been determined. Comparative sequence analysis of the M-gene of LPMV revealed the closest relationship of LPMV was to human mumps virus with a homology of 46% and 55% at the amino acid and nucleotide levels respectively. The P-gene of LPMV is transcribed to V protein mRNA and by editing of the gene to the P protein mRNA. The LPMV P-gene has the coding capacity for an additional protein of 126 amino acids, a C protein.