Experimental modification of the genome of Newcastle disease virus.: 1.: Establishment

The genome of the Newcastle disease virus (NDV) vaccine strain PHY-LMV42 (belonging to genotype 1) was cloned (Figure 1) and sequenced (Figure 2). It consists of 15 186 nucleotides and obeys the rule of six. The nucleotide positions at the genome level show approximately 11% difference from those of genotype 11 viruses (e. g. strain LaSota, B-1). The transcription regulators and start and stop signals of the individual genes are largely identical with those of the other viruses. Three support vectors containing the genes of phosphoprotein (P), nucleoprotein (NP) and L (Large) polypeptide, whose products are necessary for the assembly and function of the replicative complex are shown in Figure 3. Two expression vectors were prepared with full-length genome cDNA: one under cytomegalovirus (CMV), the other under T7-phage regulatory control. An NDV mini-genome containing CAT reporter gene was also constructed (Figure 4). Cells transfected with the mini-genome and the helper vectors produced a high amount of CAT-protein as measured by ELISA, indicating that all the constructs are functional (Table 1).