Higher classification Virus Group IV | Rank Family | |
Lower classifications Tomato mosaic virus, Pepper mild mottle virus, Sunn‑hemp mosaic virus, Tobacco rattle virus | ||
Virgaviridae is a family of positive single stranded RNA viruses. Plants serve as natural hosts. There are currently 56 species in this family, divided among 7 genera. The name of the family is derived from the Latin word virga (rod), as all viruses in this family are rod-shaped.
Contents
Taxonomy
Viruses in Virgaviridae are characterized by unique alpha-like replication proteins.
Group: ssRNA(+)
Structure
Viruses in Virgaviridae are non-enveloped, with rigid helical rod geometries, and helical symmetry. The diameter is around 20-25 nm, and virions have a central "canal." Genomes are linear, single-stranded, positive sense RNA with a 3'-tRNA like structure and no polyA tail. They may be in one, two, or three segments, depending on the genus. Coat proteins are about 19–24 kiloDaltons.
Life Cycle
Viral replication is cytoplasmic. Entry into the host cell is achieved by penetration into the host cell. Replication follows the positive stranded RNA virus replication model. Positive stranded RNA virus transcription is the method of transcription. Translation takes place by leaky scanning, and suppression of termination. The virus exits the host cell by tripartite non-tubule guided viral movement, and monopartite non-tubule guided viral movement. Plants serve as the natural host.