catalytic core domain of RNA-dependent RNA polymerase (RdRp) in the genus Flavivirus, within the family Flaviviridae of positive-sense single-stranded RNA (+ssRNA) viruses
This group contains the catalytic core domain of the RdRp of RNA viruses belonging to the Flavivirus genus within the family Flaviviridae, order Amarillovirales. The genus Flavivirus consists of more than 50 species of arthropod-borne viruses, with distinct groups infecting mosquitoes or ticks. Mammals and birds are the usual primary hosts, in which infections range from asymptomatic to severe or fatal hemorrhagic fever or neurological disease. Important human pathogens include yellow fever virus, dengue virus, Japanese encephalitis virus, West Nile virus and tick-borne encephalitis virus. Other members cause economically important diseases in domestic or wild animals. Virions of Flavivirus have a single, small, basic capsid (C) protein and two envelope proteins. They contain a single, long ORF flanked by 5'- and 3'-terminal non-coding regions, which form specific secondary structures required for genome replication and translation. Translational initiation of genomic RNA is cap dependent in the case of members of the genus Flavivirus. The RdRp domain displays a right hand with three functional subdomains, called fingers, palm, and thumb. All RdRps contain conserved polymerase motifs (A-G), located in the palm (A-E motifs) and finger (F-G) subdomains. All these motifs have been implicated in RdRp fidelity such as processes of correct incorporation and reorganization of nucleotides.