The PB1 subunit alone can catalyze cRNA synthesis, and the PA subunit in addition to the PB1 subunit is required for viral RNA synthesis in replication of the influenza virus genome.
AUTOR(ES)
Nakagawa, Y
RESUMO
We indicated that the PB1 and PA subunits of RNA polymerase and nucleoprotein (NP) can support replication of the influenza virus genome as well as transcription to yield uncapped poly(A)(+)-RNA (Y. Nakagawa, N. Kimura, T. Toyoda, K. Mizumoto, A. Ishihama, K. Oda, and S. Nakada, J. Virol. 69:728-733, 1995). To analyze the functions of the PB1 and PA subunits in replication and transcription, YP1N clones in which the PB1 and NP genes can be expressed in response to dexamethasone were established. cRNA was transcribed from model viral RNA (vRNA), but vRNA synthesis from model cRNA was not detected in YP1N clones. Furthermore, poly(A)(+)-RNA directed from model vRNA was synthesized in YP1N clones. These results indicated that PB1 and NP can support the syntheses of cRNA and poly(A)(+)-RNA and that the PA subunit, in addition to that of PB1 and to NP, is required for vRNA synthesis. In summary, the PB1 subunit is involved in the catalytic activities of nucleotide elongation, and the PA subunit may act as an allosteric modulator and cause a conformational change from a cRNA-to a vRNA-synthesizing form of the PB1 subunit.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=190666Documentos Relacionados
- The PA Subunit Is Required for Efficient Nuclear Accumulation of the PB1 Subunit of the Influenza A Virus RNA Polymerase Complex
- The RNA polymerase PB2 subunit is not required for replication of the influenza virus genome but is involved in capped mRNA synthesis.
- The influenza A virus PB2 polymerase subunit is required for the replication of viral RNA.
- Identification of two separate domains in the influenza virus PB1 protein involved in the interaction with the PB2 and PA subunits: a model for the viral RNA polymerase structure.
- Characterization of Influenza Virus PB1 Protein Binding to Viral RNA: Two Separate Regions of the Protein Contribute to the Interaction Domain