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Model suggesting that replication of influenza virus is regulated by stabilization of replicative intermediates.

ABSTRACT: The RNA-dependent RNA polymerase of influenza A virus is responsible for both transcription and replication of negative-sense viral RNA. It is thought that a "switching" mechanism regulates the transition between these activities. We demonstrate that, in the presence of preexisting viral RNA polymerase and nucleoprotein (NP), influenza A virus synthesizes both mRNA (transcription) and cRNA (replication) early in infection. We suggest that there may be no switch regulating the initiation of RNA synthesis and present a model suggesting that nascent cRNA is degraded by host cell nucleases unless it is stabilized by newly synthesized viral RNA polymerase and NP.

SUBMITTER: Vreede FT

PROVIDER: S-EPMC506943 | biostudies-literature | 2004 Sep

REPOSITORIES: biostudies-literature

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Model suggesting that replication of influenza virus is regulated by stabilization of replicative intermediates.

Vreede Frank T FT Jung Tanis E TE Brownlee George G GG

Journal of virology 20040901 17

The RNA-dependent RNA polymerase of influenza A virus is responsible for both transcription and replication of negative-sense viral RNA. It is thought that a "switching" mechanism regulates the transition between these activities. We demonstrate that, in the presence of preexisting viral RNA polymerase and nucleoprotein (NP), influenza A virus synthesizes both mRNA (transcription) and cRNA (replication) early in infection. We suggest that there may be no switch regulating the initiation of RNA s ...[more]

PMID: 15308750

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