6KUT

Structure of influenza D virus polymerase bound to vRNA promoter in Mode B conformation (Class B2)

Replaces:  6ABE

Summary for 6KUT

• Entry DOI: 10.2210/pdb6kut/pdb
• EMDB information: 9580
• Descriptor: Polymerase 3, RNA-directed RNA polymerase catalytic subunit, Polymerase PB2, ... (5 entities in total)
• Functional Keywords: influenza d virus, polymerase, cryo-em, viral protein-rna complex, viral protein/rna
• Biological source: Influenza D virus (D/swine/Oklahoma/1334/2011); More
• Total number of polymer chains: 5
• Total formula weight: 266911.02

Authors

Peng, Q.,Peng, R.,Qi, J.,Gao, G.F.,Shi, Y. (deposition date: 2019-09-02, release date: 2019-10-02, Last modification date: 2024-03-27)

Primary citation

Peng, Q.,Liu, Y.,Peng, R.,Wang, M.,Yang, W.,Song, H.,Chen, Y.,Liu, S.,Han, M.,Zhang, X.,Wang, P.,Yan, J.,Zhang, B.,Qi, J.,Deng, T.,Gao, G.F.,Shi, Y.
Structural insight into RNA synthesis by influenza D polymerase.
Nat Microbiol, 4:1750-1759, 2019

PubMed Abstract: The influenza virus polymerase uses capped RNA primers to initiate transcription, and a combination of terminal and internal de novo initiations for the two-step replication process by binding the conserved viral genomic RNA (vRNA) or complementary RNA (cRNA) promoter. Here, we determined the apo and promoter-bound influenza D polymerase structures using cryo-electron microscopy and found the polymerase has an evolutionarily conserved stable core structure with inherently flexible peripheral domains. Strikingly, two conformations (mode A and B) of the vRNA promoter were observed where the 3'-vRNA end can bind at two different sites, whereas the cRNA promoter only binds in the mode B conformation. Functional studies confirmed the critical role of the mode B conformation for vRNA synthesis via the intermediate cRNA but not for cRNA production, which is mainly regulated by the mode A conformation. Both conformations participate in the regulation of the transcription process. This work advances our understanding of the regulatory mechanisms for the synthesis of different RNA species by influenza virus polymerase and opens new opportunities for antiviral drug design.

PubMed: 31209309
DOI: 10.1038/s41564-019-0487-5

Experimental method

ELECTRON MICROSCOPY (4.1 Å)