Submitted to: American Society for Virology Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 4/11/2006
Publication Date: 7/15/2006
Citation: Estevez, C., Seal, B.S., Yu, Q. 2006. Viral rescue from an infectious clone of a mesogenic Newcastle disease virus. In: Proceedings of the 14th Annual Meeting of American Society for Virology, July 15, 2006, Madison, WI. p.217.
Technical Abstract: Reverse genetics is a powerful tool for the study of viral pathogenesis of negative stranded RNA viruses through the manipulation of genes associated with interactions of the pathogen with the host. The present work describes the generation of an infectious clone of the Newcastle disease virus Anhinga strain and initial characterization of the rescued virus. A mesogenic strain was chosen for this work because it allows for the determination of amino acid residues that are important for attenuation as well as for enhancement of pathogenicity of the virus. During the assembly of the infectious clone and viral rescue work, two mutations in the nucleocapsid (N) gene and one mutation in the polymerase (L) gene were found to interfere with function of these proteins. Mutations Cys-78-Arg and Arg-222-Ser in the N gene completely abrogated the function of the protein, while mutation Val-1190-Ala of the L gene profoundly diminished the ability of the protein to function. This was evidenced by the reduced expression of a reporter gene included in a minireplicon system constructed to assess functionality of the supporting proteins necessary for viral rescue from the infectious clone. Correction of these mutations in the supporting proteins and infectious clone resulted in viral rescue. Initial characterization of the rescued virus revealed that the initial viral population obtained had a diminished ability to hemagglutinate chicken RBC, but was still a mesogenic virus, as evidenced by the results of the mean death time assay in specific pathogen-free embryonating chicken eggs.