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TRIM79?, an interferon-stimulated gene product, restricts tick-borne encephalitis virus replication by degrading the viral RNA polymerase.

ABSTRACT: In response to virus infection, type I interferons (IFNs) induce several genes, most of whose functions are largely unknown. Here, we show that the tripartite motif (TRIM) protein, TRIM79?, is an IFN-stimulated gene (ISG) product that specifically targets tick-borne encephalitis virus (TBEV), a Flavivirus that causes encephalitides in humans. TRIM79? restricts TBEV replication by mediating lysosome-dependent degradation of the flavivirus NS5 protein, an RNA-dependent RNA polymerase essential for virus replication. NS5 degradation was specific to tick-borne flaviviruses, as TRIM79? did not recognize NS5 from West Nile virus (WNV) or inhibit WNV replication. In the absence of TRIM79?, IFN-? was less effective in inhibiting tick-borne flavivirus infection of mouse macrophages, highlighting the importance of a single virus-specific ISG in establishing an antiviral state. The specificity of TRIM79? for TBEV reveals a remarkable ability of the innate IFN response to discriminate between closely related flaviviruses.

SUBMITTER: Taylor RT

PROVIDER: S-EPMC3182769 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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TRIM79α, an interferon-stimulated gene product, restricts tick-borne encephalitis virus replication by degrading the viral RNA polymerase.

Taylor R Travis RT Lubick Kirk J KJ Robertson Shelly J SJ Broughton James P JP Bloom Marshall E ME Bresnahan Wade A WA Best Sonja M SM

Cell host & microbe 20110901 3

In response to virus infection, type I interferons (IFNs) induce several genes, most of whose functions are largely unknown. Here, we show that the tripartite motif (TRIM) protein, TRIM79α, is an IFN-stimulated gene (ISG) product that specifically targets tick-borne encephalitis virus (TBEV), a Flavivirus that causes encephalitides in humans. TRIM79α restricts TBEV replication by mediating lysosome-dependent degradation of the flavivirus NS5 protein, an RNA-dependent RNA polymerase essential for ...[more]

PMID: 21925107

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Dataset Information

TRIM79?, an interferon-stimulated gene product, restricts tick-borne encephalitis virus replication by degrading the viral RNA polymerase.

Publications

TRIM79α, an interferon-stimulated gene product, restricts tick-borne encephalitis virus replication by degrading the viral RNA polymerase.

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