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A combination of naturally occurring mutations in North American West Nile virus nonstructural protein genes and in the 3' untranslated region alters virus phenotype.

ABSTRACT: We previously reported mutations in North American West Nile viruses (WNVs) with a small-plaque (sp), temperature-sensitive (ts), and/or mouse-attenuated (att) phenotype. Using an infectious clone, site-directed mutations and 3' untranslated region (3'UTR) exchanges were introduced into the WNV NY99 genome. Characterization of mutants demonstrated that a combination of mutations involving the NS4B protein (E249G) together with either a mutation in the NS5 protein (A804V) or three mutations in the 3'UTR (A10596G, C10774U, A10799G) produced sp, ts, and/or att variants. These results suggested that the discovery of North American WNV-phenotypic variants is rare because of the apparent requirement of concurrent polygenic mutations.

SUBMITTER: Davis CT

PROVIDER: S-EPMC1900292 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature

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A combination of naturally occurring mutations in North American West Nile virus nonstructural protein genes and in the 3' untranslated region alters virus phenotype.

Davis C Todd CT Galbraith Sareen E SE Zhang Shuliu S Whiteman Melissa C MC Li Li L Kinney Richard M RM Barrett Alan D T AD

Journal of virology 20070321 11

We previously reported mutations in North American West Nile viruses (WNVs) with a small-plaque (sp), temperature-sensitive (ts), and/or mouse-attenuated (att) phenotype. Using an infectious clone, site-directed mutations and 3' untranslated region (3'UTR) exchanges were introduced into the WNV NY99 genome. Characterization of mutants demonstrated that a combination of mutations involving the NS4B protein (E249G) together with either a mutation in the NS5 protein (A804V) or three mutations in th ...[more]

PMID: 17376926

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