catalytic core domain of RNA-dependent RNA polymerase (RdRp) in the family Caliciviridae of positive-sense single-stranded RNA [(+)ssRNA] viruses
This group contains the catalytic core domain of RdRp of RNA viruses belonging to the family Caliciviridae, order Picornavirales. Member viruses have a viral (+)ssRNA genome, which is not segmented. The family Caliciviridae, includes eleven genera: seven genera of which infect mammals (Lagovirus, Norovirus, Nebovirus, Recovirus, Sapovirus, Valovirus, and Vesivirus), two genera of which infect birds (Bavovirus, Nacovirus), and two genera of which infect fish (Minovirus and Salovirus). Each genus includes 1-2 species. Human noroviruses are a leading cause of acute gastroenteritis in humans. Furthermore, unclassified caliciviruses have been detected in geese, yellowfin seabream, greater green snake, arctic lamprey, frogs and various Australian birds, highlighting the wide host range of viruses in the family Caliciviridae. 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.
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