The Consequences of Reconfiguring the Ambisense S Genome Segment of Rift Valley Fever Virus on Viral Replication in Mammalian and Mosquito Cells and for Genome Packaging

• DOI: 10.1371/journal.ppat.1003922
• Publication Date: 2014-02-13T22:04:36Z
• Authors: Benjamin Brennan; Stephen R. Welch; Richard M. Elliott
• Keywords: Subgenomic mRNA; Reverse Genetics

Rift Valley fever virus (RVFV, family Bunyaviridae) is a mosquito-borne pathogen of both livestock and humans, found primarily in Sub-Saharan Africa the Arabian Peninsula. The viral genome comprises two negative-sense (L M segments) one ambisense (S segment) RNAs that encode seven proteins. S segment encodes nucleocapsid (N) protein nonstructural (NSs) positive-sense, though NSs cannot be translated directly from but rather specific subgenomic mRNA. Using reverse genetics we generated virus, designated rMP12:S-Swap, which N expressed locus within genomic RNA. In cells infected with rMP12:S-Swap at higher levels respect to than parental rMP12 virus. Despite being main interferon antagonist determinant virulence, growth was attenuated mammalian gave small plaque phenotype. increased abundance did not lead faster inhibition host cell synthesis or transcription cells. cultured mosquito cells, however, infection resulted death establishment persistence as seen rMP12. Finally, altering composition led differential packaging ratio antigenomic RNA into virions. Our results highlight plasticity RVFV provide useful experimental tool investigate further mechanism segmented genome.