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A 5' RNA element promotes dengue virus RNA synthesis on a circular genome.

ABSTRACT: The mechanisms of RNA replication of plus-strand RNA viruses are still unclear. Here, we identified the first promoter element for RNA synthesis described in a flavivirus. Using dengue virus as a model, we found that the viral RdRp discriminates the viral RNA by specific recognition of a 5' element named SLA. We demonstrated that RNA-RNA interactions between 5' and 3' end sequences of the viral genome enhance dengue virus RNA synthesis only in the presence of an intact SLA. We propose a novel mechanism for minus-strand RNA synthesis in which the viral polymerase binds SLA at the 5' end of the genome and reaches the site of initiation at the 3' end via long-range RNA-RNA interactions. These findings provide an explanation for the strict requirement of dengue virus genome cyclization during viral replication.

SUBMITTER: Filomatori CV

PROVIDER: S-EPMC1553207 | biostudies-literature | 2006 Aug

REPOSITORIES: biostudies-literature

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A 5' RNA element promotes dengue virus RNA synthesis on a circular genome.

Filomatori Claudia V CV Lodeiro Maria F MF Alvarez Diego E DE Samsa Marcelo M MM Pietrasanta Lía L Gamarnik Andrea V AV

Genes & development 20060801 16

The mechanisms of RNA replication of plus-strand RNA viruses are still unclear. Here, we identified the first promoter element for RNA synthesis described in a flavivirus. Using dengue virus as a model, we found that the viral RdRp discriminates the viral RNA by specific recognition of a 5' element named SLA. We demonstrated that RNA-RNA interactions between 5' and 3' end sequences of the viral genome enhance dengue virus RNA synthesis only in the presence of an intact SLA. We propose a novel me ...[more]

PMID: 16882970

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