Notes on Family: Virgaviridae
rigid rods
Contents
General Description
This family was created in 2008 to include all the rod-shaped ssRNA+ plant viruses with with a 3'- t-RNA like structure and no polyA tail. Their replication proteins form a single family within the alpha-like supergroup. The name is from the Latin
virga (= rod). The genus
Benyvirus is the only other rod-shaped plant virus genus but this has a polyadenylated gene and the replication protein is only very distantly related to that of members of the
Virgaviridae.
Morphology
Virions rod-shaped, not enveloped, usually straight, with distinct central canal and 20-23 nm in diameter. The distribution of particle lengths differs between the genera.
Genomen
Linear, single stranded, positive sense RNA with a 3'- t-RNA like structure and no polyA tail . Depending on the genus there are either 1, 2 or 3 genomic RNAs packaged in separate particles.
Genera in the Family
- Furovirus: bipartite genome; transmitted by plasmodiophorids; '30K' movement protein; coat protein has readthrough domain associated with vector transmission
- Hordeivirus: tripartite genome; seed-transmitted; RNA polymerase encoded separately from other replication proteins on RNA2; triple gene block movement proteins
- Pecluvirus: bipartite genome; transmitted by plasmodiophorids; triple gene block movement proteins
- Pomovirus: tripartite genome; transmitted by plasmodiophorids; triple gene block movement proteins; coat protein has readthrough domain associated with vector transmission
- Tobamovirus: monopartite genome; mechanically transmitted with no known vectors; '30K' movement protein
- Tobravirus: bipartite genome; transmitted by nematodes; '30K' movement protein