Tweet
Nucleic Acids Res. 2016 Sep 30. pii: gkw884. [Epub ahead of print]
Single-molecule FRET reveals the pre-initiation and initiation conformations of influenza virus promoter RNA.
Robb NC1, Te Velthuis AJ2, Wieneke R3, Tamp? R3, Cordes T4, Fodor E5, Kapanidis AN6.
Author information
Abstract
Influenza viruses have a segmented viral RNA (vRNA) genome, which is replicated by the viral RNA-dependent RNA polymerase (RNAP). Replication initiates on the vRNA 3' terminus, producing a complementary RNA (cRNA) intermediate, which serves as a template for the synthesis of new vRNA. RNAP structures show the 3' terminus of the vRNA template in a pre-initiation state, bound on the surface of the RNAP rather than in the active site; no information is available on 3' cRNA binding. Here, we have used single-molecule F?rster resonance energy transfer (smFRET) to probe the viral RNA conformations that occur during RNAP binding and initial replication. We show that even in the absence of nucleotides, the RNAP-bound 3' termini of both vRNA and cRNA exist in two conformations, corresponding to the pre-initiation state and an initiation conformation in which the 3' terminus of the viral RNA is in the RNAP active site. Nucleotide addition stabilises the 3' vRNA in the active site and results in unwinding of the duplexed region of the promoter. Our data provide insights into the dynamic motions of RNA that occur during initial influenza replication and has implications for our understanding of the replication mechanisms of similar pathogenic viruses.
? The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.
PMID: 27694620 DOI: 10.1093/nar/gkw884
[PubMed - as supplied by publisher] Free full text
Single-molecule FRET reveals the pre-initiation and initiation conformations of influenza virus promoter RNA.
Robb NC1, Te Velthuis AJ2, Wieneke R3, Tamp? R3, Cordes T4, Fodor E5, Kapanidis AN6.
Author information
Abstract
Influenza viruses have a segmented viral RNA (vRNA) genome, which is replicated by the viral RNA-dependent RNA polymerase (RNAP). Replication initiates on the vRNA 3' terminus, producing a complementary RNA (cRNA) intermediate, which serves as a template for the synthesis of new vRNA. RNAP structures show the 3' terminus of the vRNA template in a pre-initiation state, bound on the surface of the RNAP rather than in the active site; no information is available on 3' cRNA binding. Here, we have used single-molecule F?rster resonance energy transfer (smFRET) to probe the viral RNA conformations that occur during RNAP binding and initial replication. We show that even in the absence of nucleotides, the RNAP-bound 3' termini of both vRNA and cRNA exist in two conformations, corresponding to the pre-initiation state and an initiation conformation in which the 3' terminus of the viral RNA is in the RNAP active site. Nucleotide addition stabilises the 3' vRNA in the active site and results in unwinding of the duplexed region of the promoter. Our data provide insights into the dynamic motions of RNA that occur during initial influenza replication and has implications for our understanding of the replication mechanisms of similar pathogenic viruses.
? The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.
PMID: 27694620 DOI: 10.1093/nar/gkw884
[PubMed - as supplied by publisher] Free full text