RRC ID 70001
Author Naito T, Momose F, Kawaguchi A, Nagata K.
Title Involvement of Hsp90 in assembly and nuclear import of influenza virus RNA polymerase subunits.
Journal J Virol
Abstract Transcription and replication of the influenza virus RNA genome occur in the nuclei of infected cells through the viral RNA-dependent RNA polymerase consisting of PB1, PB2, and PA. We previously identified a host factor designated RAF-1 (RNA polymerase activating factor 1) that stimulates viral RNA synthesis. RAF-1 is found to be identical to Hsp90. Here, we examined the intracellular localization of Hsp90 and viral RNA polymerase subunits and their molecular interaction. Hsp90 was found to interact with PB2 and PB1, and it was relocalized to the nucleus upon viral infection. We found that the nuclear transport of Hsp90 occurs in cells expressing PB2 alone. The nuclear transport of Hsp90 was in parallel with that of the viral RNA polymerase binary complexes, either PB1 and PB2 or PB1 and PA, as well as with that of PB2 alone. Hsp90 also interacted with the binary RNA polymerase complex PB1-PB2, and it was dissociated from the PB1-PB2 complex upon its association with PA. Furthermore, Hsp90 could form a stable PB1-PB2-Hsp90 complex prior to the formation of a ternary polymerase complex by the assembly of PA in the infected cells. These results suggest that Hsp90 is involved in the assembly and nuclear transport of viral RNA polymerase subunits, possibly as a molecular chaperone for the polymerase subunits prior to the formation of a mature ternary polymerase complex.
Volume 81(3)
Pages 1339-49
Published 2007-2-1
DOI 10.1128/JVI.01917-06
PII JVI.01917-06
PMID 17121807
PMC PMC1797515
MeSH HSP90 Heat-Shock Proteins / metabolism* HeLa Cells Humans Influenza A virus / enzymology* Influenza A virus / immunology Nucleoproteins RNA, Viral / biosynthesis RNA, Viral / metabolism RNA-Dependent RNA Polymerase RNA-Directed DNA Polymerase / biosynthesis* RNA-Directed DNA Polymerase / genetics RNA-Directed DNA Polymerase / immunology Viral Proteins / metabolism* Virus Assembly* Virus Replication
IF 4.501
DNA material PB2cMyc on pCAGGS (RDB19452) PAcFLAG on pCAGGS (RDB19451) PB2cHA on pCAGGS (RDB19450) PB1cFLAG on pCAGGS (RDB19449)