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The V protein of mumps virus plays a critical role in pathogenesis.

ABSTRACT: Mumps virus (MuV) causes an acute infection in humans characterized by a wide array of symptoms ranging from relatively mild manifestations, such as parotitis, to more-severe complications, such as meningitis and encephalitis. Widespread mumps vaccination has reduced mumps incidence dramatically; however, outbreaks still occur in vaccinated populations. The V protein of MuV, when expressed in cell culture, blocks interferon (IFN) expression and signaling and interleukin-6 (IL-6) signaling. In this work, we generated a recombinant MuV incapable of expressing the V protein (rMuV?V). The rescued MuV was derived from a clinical wild-type isolate from a recent outbreak in the United States (MuV(Iowa/US/06), G genotype). Analysis of the virus confirmed the roles of V protein in blocking IFN expression and signaling and IL-6 signaling. We also found that the rMuV(Iowa/US/06)?V virus induced high levels of IL-6 expression in vitro, suggesting that V plays a role in reducing IL-6 expression. In vivo, the rMuV(Iowa/US/06)?V virus was highly attenuated, indicating that the V protein plays an essential role in viral virulence.

SUBMITTER: Xu P

PROVIDER: S-EPMC3264346 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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The V protein of mumps virus plays a critical role in pathogenesis.

Xu Pei P Luthra Priya P Li Zhuo Z Fuentes Sandra S D'Andrea James Alexander JA Wu Jianguo J Rubin Steven S Rota Paul A PA He Biao B

Journal of virology 20111116 3

Mumps virus (MuV) causes an acute infection in humans characterized by a wide array of symptoms ranging from relatively mild manifestations, such as parotitis, to more-severe complications, such as meningitis and encephalitis. Widespread mumps vaccination has reduced mumps incidence dramatically; however, outbreaks still occur in vaccinated populations. The V protein of MuV, when expressed in cell culture, blocks interferon (IFN) expression and signaling and interleukin-6 (IL-6) signaling. In th ...[more]

PMID: 22090137

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The V protein of mumps virus plays a critical role in pathogenesis.

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The V protein of mumps virus plays a critical role in pathogenesis.

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