7EKJ

Crystals structure of classical swine fever virus NS5B (residues 91-694)

Summary for 7EKJ

• Entry DOI: 10.2210/pdb7ekj/pdb
• Descriptor: Classical swine fever virus NS5B (1 entity in total)
• Functional Keywords: polymerase, transferase
• Biological source: Classical swine fever virus
• Total number of polymer chains: 1
• Total formula weight: 70418.36

Authors

Liu, W.,Gong, P. (deposition date: 2021-04-05, release date: 2021-07-28, Last modification date: 2023-11-29)

Primary citation

Zhang, B.Y.,Liu, W.,Jia, H.,Lu, G.,Gong, P.
An induced-fit de novo initiation mechanism suggested by a pestivirus RNA-dependent RNA polymerase.
Nucleic Acids Res., 49:8811-8821, 2021

PubMed Abstract: Viral RNA-dependent RNA polymerases (RdRPs) play central roles in the genome replication and transcription processes of RNA viruses. RdRPs initiate RNA synthesis either in primer-dependent or de novo mechanism, with the latter often assisted by a 'priming element' (PE) within the RdRP thumb domain. However, RdRP PEs exhibit high-level structural diversity, making it difficult to reconcile their conserved function in de novo initiation. Here we determined a 3.1-Å crystal structure of the Flaviviridae classical swine fever virus (CSFV) RdRP with a relative complete PE. Structure-based mutagenesis in combination with enzymology data further highlights the importance of a glycine residue (G671) and the participation of residues 665-680 in RdRP initiation. When compared with other representative Flaviviridae RdRPs, CSFV RdRP PE is structurally distinct but consistent in terminal initiation preference. Taken together, our work suggests that a conformational change in CSFV RdRP PE is necessary to fulfill de novo initiation, and similar 'induced-fit' mechanisms may be commonly taken by PE-containing de novo viral RdRPs.

PubMed: 34365500
DOI: 10.1093/nar/gkab666

Experimental method

X-RAY DIFFRACTION (3.06 Å)