Construction of recombinant fowlpox virus expressing fusion gene of Newcastle disease virus

The gene expression cassette was constructed with the fusion protein gene fragment from Newcastle disease virus(NDV) by RT-PCR,along with compound promoters of fowlpox virus and SV40 polyA tail signal sequence.In the interaction of liposome,the recombinant virus rFPVFGFP was generated via co-transfection of the fowlpox virus genome and the delivery vector,in which tandem insertion of the fusion gene cassette and loxp-GFP-loxP sequence into the homologous arm gene of fowlpox virus,into chick embryo fibroblast cell.After second transfection,the GFP gene in recombinant genome was removed automatically by site specific recombination of Cre-loxP system and then the rFPVF was gained only containing fusion gene of NDV.The rFPVF recombinant could multiplicate stably in CEF and the fusion protein expression product got immunogenic ability to promote the chicken to produce neutralizing antibody against NDV.