Download MendeleyAn induced-fit de novo initiation mechanism suggested by a pestivirus RNA-dependent RNA polymerase.
Zhang, B.Y., Liu, W., Jia, H., Lu, G., Gong, P.(2021) Nucleic Acids Res 49: 8811-8821
- PubMed: 34365500
- DOI: https://doi.org/10.1093/nar/gkab666
- Primary Citation of Related Structures:
7EKJ - 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.
Organizational Affiliation:
Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, No.44 Xiao Hong Shan, Wuhan, Hubei 430071, China.
