Cloning and sequencing of the mumps virus fusion protein gene.

The fusion protein (F) gene of mumps virus was cloned from a cDNA library constructed from infected cell mRNA. The F-specific plasmids were identified by hybridization to a degenerate oligonucleotide probe whose sequence was deduced from the N-terminal amino acid sequence of the F2 protein. The complete nucleotide sequence of the F gene was determined. The gene is 1786 nucleotides long and encodes one long open reading frame of 538 amino acids. The F protein has a 19-amino acid signal peptide cleaved between Cys and Val residues. The cleavage site for activation of the F0 protein into the mature F1,2 is Arg-Arg-His-Lys-Arg. A stretch of 30 hydrophobic amino acids near the C-terminus of the protein is followed by several charged amino acids and appears to serve as the anchoring domain for the protein in the lipid bilayer. The F gene of mumps virus is highly related to the F gene of the paramyxovirus SV-5.