Peter T. Emmerson

Insertion of the fusion gene from Newcastle disease virus into a non-essential region in the terminal repeats of fowlpox virus and demonstration of protective immunity induced by the recombinant.

In this paper we report on the identification of non-essential genes in the terminal repeats of the avipox-virus fowlpox virus and the use of these as insertion sites in a vector system. Foreign genes inserted into these sites are shown to be present in two copies in the resultant recombinant virus. To test the potential use of this vector as a live vaccine the fusion gene of Newcastle disease virus has been inserted into a vaccine strain of fowlpox virus and inoculated into chickens. The experiments demonstrate the ability of the recombinant to protect chickens against challenge by a virulent strain of Newcastle disease virus and to elicit the formation of an anti-fusion protein antibody.

Nucleotide Sequence of the Gene Encoding the Fusion Glycoprotein of Newcastle Disease Virus

The nucleotide sequence of the gene encoding the fusion (F) glycoprotein of the Beaudette C strain of Newcastle disease virus (NDV) has been determined from cDNA clones obtained from virion RNA. The gene is 1792 nucleotides long, including mRNA start and polyadenylation signals typical of paramyxoviruses. The single open reading frame encodes a polypeptide of 553 amino acids, with a predicted molecular weight of 59042. The F polypeptide has three regions of high hydrophobicity: an N-terminal signal peptide, the N terminus of F1 (known from protein sequencing) and a C-terminal membrane-spanning region by which the F glycoprotein is anchored to the membrane. The cleavage site of F0 is located in a highly basic region of the F polypeptide. Five potential asparagine-linked glycosylation sites are present in the amino acid sequence, of which one is in F2 and the others in F1. Comparison of the NDV F amino acid sequence to those from other paramyxoviruses reveals homology to Sendai virus, simian virus 5 and human respiratory syncytial virus. There is also limited homology between the N terminus of F1 of NDV and the N termini of HA2 of influenza viruses. Post-translational modifications of the NDV F polypeptide are discussed in the light of information provided by the amino acid sequence.

Location of a Neutralizing Epitope for the Haemagglutinin-Neuraminidase Glycoprotein of Newcastle Disease Virus

The binding site of a monoclonal antibody to the haemagglutinin-neuraminidase (HN) polypeptide of Newcastle disease virus (NDV) has been located. Complementary DNA or synthetic oligonucleotides corresponding to portions of the HN gene were cloned into the Escherichia coli vector pUC19 and fragments of the HN protein were thereby fused to the alpha-peptide of beta-galactosidase. Western blot analysis of E. coli lysates containing expressed fragments of the HN cDNA or synthetic oligonucleotides identified an antibody-binding peptide (Asp-Glu-Gln-Asp-Tyr-Gln-Ile-Arg; amino acid residues 346 to 353). Nucleotide sequence analysis of an antibody-resistant mutant of NDV revealed a Glu (wild-type) to Lys (mutant) substitution within the above sequence. The methods described could be useful for the location of continuous epitopes of other polypeptides.