9V44

Coupling of polymerase-nucleoprotein-RNA in an influenza virus mini ribonucleoprotein complex

Summary for 9V44

• Entry DOI: 10.2210/pdb9v44/pdb
• EMDB information: 64766
• Descriptor: Polymerase acidic protein, RNA-directed RNA polymerase catalytic subunit, Polymerase basic protein 2, ... (6 entities in total)
• Functional Keywords: influenza virus, ribonucleoprotein complex, polymerase, cryo-em, viral protein/rna, viral protein-rna complex
• Biological source: Influenza A virus (A/Victoria/3/1975(H3N2)); More
• Total number of polymer chains: 6
• Total formula weight: 324051.14

Authors

Kang, H.,Yang, Y.,Liu, Y.,Li, M.,Zhang, L.,Lin, Y.,Rao, Z.,Lou, Z. (deposition date: 2025-05-22, release date: 2025-10-08, Last modification date: 2025-11-26)

Primary citation

Kang, H.,Yang, Y.,Liu, Y.,Li, M.,Zhang, L.,Lin, Y.,Witte, L.,Chen, K.Y.,Song, W.,Xu, Z.,He, X.,Guddat, L.W.,Guo, Y.,Yan, L.,Gao, Y.,Fodor, E.,Rao, Z.,Lou, Z.
Coupling of polymerase-nucleoprotein-RNA in an influenza virus mini ribonucleoprotein complex.
Nat Commun, 16:9741-9741, 2025

PubMed Abstract: Influenza virus ribonucleoprotein complexes (RNPs), composed of the polymerase complex (FluPol), nucleoprotein (NP), and RNA, are essential for replication and transcription. We report atomic-resolution cryo-EM structures of mini-vRNPs in two states: FluPol located inside (State-In) or at the outer rim (State-Out) of the NP-RNA ring. In both states, the 5' and 3' termini of vRNA are bound to FluPol as previously reported. One NP (NP-0) contacts PA/PB1 of FluPol and binds the distal double-stranded vRNA promoter, with its D72-K90 loop inserting into the RNA fork; separated strands occupy NP-0 RNA-binding grooves. Grooves from other NPs form a continuous RNA-protective path, consistent with negative-strand RNA virus mechanisms. In State-In, interfaces for FluPol dimerization or Pol II interaction are blocked, but fully exposed in State-Out. These structures reveal detailed FluPol-NP-RNA coupling and suggest a conformational shift in RNPs during the viral life cycle.

PubMed: 41188214
DOI: 10.1038/s41467-025-64741-z

Experimental method

ELECTRON MICROSCOPY (2.97 Å)