Nucleotide sequence of the gene encoding the Newcastle disease virus fusion protein and comparisons of paramyxovirus fusion protein sequences.

The nucleotide sequence of cloned cDNA copies of the mRNA encoding the Newcastle disease virus fusion protein was determined. A single open reading frame in the sequence encodes a hydrophobic protein of 553 amino acids with a calculated molecular weight of 58 978. The previously determined protein sequence of the amino terminus of the F1 (Richardson, G.D. et al. (1980) Virology 105, 205-222) was located within the predicted protein sequence. The predicted protein sequence contains a hydrophobic stretch of 29 amino acids near the carboxy terminal end and likely represents the membrane spanning region of the protein. The F2 portion of the sequence contains one glycosylation site while F1 contains four which are potentially used. The predicted sequence contains 13 cysteine residues. Comparison of the NDV fusion protein sequence with three other paramyxovirus fusion protein sequences reveals little homology common to all four viruses except for the amino terminus of the F1 proteins. However, the positions of the cysteine residues within the sequence are conserved, particularly among the members of the paramyxovirus subgroup, suggesting the importance of disulfide bond formation in the conformation of paramyxovirus fusion proteins.