4WSB

Bat Influenza A polymerase with bound vRNA promoter

Summary for 4WSB

• Entry DOI: 10.2210/pdb4wsb/pdb
• Descriptor: Polymerase PA, RNA-directed RNA polymerase catalytic subunit, Polymerase PB2, ... (8 entities in total)
• Functional Keywords: transferase-rna complex, transferase/rna
• Biological source: Influenza A virus; More
• Total number of polymer chains: 5
• Total formula weight: 274856.71

Authors

Cusack, S.,Pflug, A.,Guilligay, D.,Reich, S. (deposition date: 2014-10-26, release date: 2014-11-19, Last modification date: 2024-01-10)

Primary citation

Reich, S.,Guilligay, D.,Pflug, A.,Malet, H.,Berger, I.,Crepin, T.,Hart, D.,Lunardi, T.,Nanao, M.,Ruigrok, R.W.,Cusack, S.
Structural insight into cap-snatching and RNA synthesis by influenza polymerase.
Nature, 516:361-366, 2014

PubMed Abstract: Influenza virus polymerase uses a capped primer, derived by 'cap-snatching' from host pre-messenger RNA, to transcribe its RNA genome into mRNA and a stuttering mechanism to generate the poly(A) tail. By contrast, genome replication is unprimed and generates exact full-length copies of the template. Here we use crystal structures of bat influenza A and human influenza B polymerases (FluA and FluB), bound to the viral RNA promoter, to give mechanistic insight into these distinct processes. In the FluA structure, a loop analogous to the priming loop of flavivirus polymerases suggests that influenza could initiate unprimed template replication by a similar mechanism. Comparing the FluA and FluB structures suggests that cap-snatching involves in situ rotation of the PB2 cap-binding domain to direct the capped primer first towards the endonuclease and then into the polymerase active site. The polymerase probably undergoes considerable conformational changes to convert the observed pre-initiation state into the active initiation and elongation states.

PubMed: 25409151
DOI: 10.1038/nature14009

Experimental method

X-RAY DIFFRACTION (2.65 Å)