The viral nucleoprotein (NP) segment of AIV was genetically modified to co-express GFP11 of self-assembling split-GFP, and the recombinant AIV with the modified NP segment was generated by plasmid-based reverse genetics. Infection with the recombinant AIV in cultured chicken cells was visualized by transient transfection with a GFP1 -10 expression vector and fluorescence was observed in the cells at 96 hours post-inoculation. Virus titer of the recombinant AIV in embryonated eggs was comparable to wild type AIV titers at 48 h post inoculation. The inserted sequence encoding GFP11 was stable for up to ten passages in embryonated eggs.
A visualization system for AIV-infected cells using split-GFP was developed. This method could be used to understand AIV infection dynamics in cells.