Notes on Genus: Avenavirus
icosahedra
Type member: Oat chlorotic stunt virus
Contents
General Description
The genus
Avenavirus is one of 11 genera in the family
Tombusviridae. The name is based on
Avena, the scientific name of oat (the host of the type member). All the genera are morphologically similar, with icosahedral particles and small, (usually) monopartite ss RNA genomes. The single member of this genus has the largest coat protein of any member of the family (48.2 kDa) and four (rather than the usual five or six) open reading frames. The coat protein region shows most similarity with members of the genus
Tombusvirus whilst the size and predicted strategy of the genome seem to be intermediate between that of the
Carmovirus and
Tombusvirus genera.
Morphology
Virions isometric (icosahedral), not enveloped, 35 nm in diameter.
Genome
Monopartite, linear, single stranded, positive sense RNA approx. 4.4 kb in size. The 3' terminus has no poly(A) tract.
Genus Genomic Organization
The RNA is translated into three or four putative products.
Type Member Genomic Organization
The RNA is translated into three or perhaps four products:
| 1. | 23 kDa | putative polymerase |
| 2. | 84 kDa | polymerase, produced by readthrough of 1 |
| 3. | 48 kDa | coat protein |
| 4. | 8 kDa | possible ORF of unknown function |