Permutation of the active site of putative RNA-dependent RNA polymerase in a newly identified species of plant alpha-like virus.
To direct the genome synthesis, RNA viruses without a DNA stage in the replication cycle use RNA-dependent RNA polymerase (RdRp). All RdRps have conserved right hand-like shape that includes characteristic A-->B-->C sequence motifs forming the active site. Recently, the structural permutation of the RdRp active site (C-->A-->B) has been described in few double-stranded RNA birnaviruses and a subset of positive-stranded RNA tetraviruses distantly related to Picorna-like viruses. Here we describe a permuted RdRp in the newly identified plant alpha-like virus with 6.5 kb-long polyadenylated genome, dubbed Grapevine virus Q (GVQ). The multi-domain layout and sequence similarities place GVQ into the genus Marafivirus of the family Tymoviridae. In contrast to other tymovirids, GVQ has 21 amino acid residues corresponding to the motif C relocated upstream of the motif A in the putative RdRp. This unique sequence characteristic was extensively verified and identified in several GVQ isolates infecting wild and cultivated Vitis and Rubus spp.
Department of Entomology, Mississippi State University, Mississippi State, MS 39762, USA. ss501@msstate.edu
Sead
S
Sabanadzovic
Nina Abou
NA
Ghanem-Sabanadzovic
Alexander E
AE
Gorbalenya
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D020134:Catalytic Domain; D016000:Cluster Analysis; D008969:Molecular Sequence Data; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase / Q000737:chemistry* / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D046830:Tymoviridae / Q000145:classification / Q000201:enzymology* / Q000235:genetics*; D014764:Viral Proteins / Q000235:genetics*; D027843:Vitis / Q000821:virology
D012367:RNA, Viral; D014764:Viral Proteins; D012324:RNA-Dependent RNA Polymerase