Notes on Genus: Torradovirus
Type member: Tomato torrado virus
- Members of this Genus
- General Description
- Electron Micrograph
- Genus Genomic Organization
- Genome Map
- Type Member Genomic Organization
- All Known Sequences
- Curated Sequences
General DescriptionThe genus Torradovirus (from the type member Tomato torrado virus) is one of the genera within the plant picornavirus family Secoviridae. It contains viruses reported to be transmitted by whiteflies with three distinct coat protein subunits and an additional ORF at the 5'-end of RNA2 in addition to the polyprotein typical of members of this family.
MorphologyVirions isometric (icosahedral), not enveloped, about 30 nm in diameter.
GenomeBipartite, linear, single stranded, positive sense RNA. The 3'- terminus of each RNA has a poly(A) tract and the 5'- terminus has a genome-linked protein (VPg).
Genus Genomic OrganizationEach RNA is translated into a polyprotein, which is then processed by a series of steps into functional proteins: RNA1 encodes proteins necessary for replication while the cell-to-cell movement protein and coat proteins are encoded on RNA2.
Type Member Genomic OrganizationRNA1 (7.8 kb) produces a polyprotein of 241 kDa processed into mature peptides. Cleavage sites have not been determined but these are expected to include a Processing regulator, Nucleotide binding protein, VPg (genome-linked protein), Protease and the RNA-dependent RNA polymerase.
RNA2 (5.4 kb) has a small (20 kDa) ORF predicted near the 5'-terminus and a polyprotein of 134 kDa in which a movement protein can be identified and three separate coat proteins of about 35, 26 and 23 kDa.