A Structural Overview of RNA-Dependent RNA Polymerases from the Flaviviridae Family
AbstractRNA-dependent RNA polymerases (RdRPs) from the Flaviviridae family are representatives of viral polymerases that carry out RNA synthesis through a de novo initiation mechanism. They share a ≈ 600-residue polymerase core that displays a canonical viral RdRP architecture resembling an encircled right hand with palm, fingers, and thumb domains surrounding the active site. Polymerase catalytic motifs A–E in the palm and motifs F/G in the fingers are shared by all viral RdRPs with sequence and/or structural conservations regardless of the mechanism of initiation. Different from RdRPs carrying out primer-dependent initiation, Flaviviridae and other de novo RdRPs utilize a priming element often integrated in the thumb domain to facilitate primer-independent initiation. Upon the transition to the elongation phase, this priming element needs to undergo currently unresolved conformational rearrangements to accommodate the growth of the template-product RNA duplex. In the genera of Flavivirus and Pestivirus, the polymerase module in the C-terminal part of the RdRP protein may be regulated in cis by the N-terminal region of the same polypeptide. Either being a methyltransferase in Flavivirus or a functionally unclarified module in Pestivirus, this region could play auxiliary roles for the canonical folding and/or the catalysis of the polymerase, through defined intra-molecular interactions. View Full-Text
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Wu, J.; Liu, W.; Gong, P. A Structural Overview of RNA-Dependent RNA Polymerases from the Flaviviridae Family. Int. J. Mol. Sci. 2015, 16, 12943-12957.
Wu J, Liu W, Gong P. A Structural Overview of RNA-Dependent RNA Polymerases from the Flaviviridae Family. International Journal of Molecular Sciences. 2015; 16(6):12943-12957.Chicago/Turabian Style
Wu, Jiqin; Liu, Weichi; Gong, Peng. 2015. "A Structural Overview of RNA-Dependent RNA Polymerases from the Flaviviridae Family." Int. J. Mol. Sci. 16, no. 6: 12943-12957.