Notes on Genus: Aureusvirus
icosahedra
Type member: Pothos latent virus
Contents
General Description
The genus
Aureusvirus (from the scientific name of the host of the type member,
Scindapsus aureus) is one of 11 genera in the family
Tombusviridae. All the genera are morphologically similar, with icosahedral particles and small, (usually) monopartite ss RNA genomes. The genome (<4.6 kb) is smaller than those of members of the genus
Tombusvirus but its organization is virtually identical. Virions accumulate in great quantity in the cytoplasm, often forming crystalline aggregates, and in bubble-like evaginations of the tonoplast protruding into the vacuole.
Morphology
Virions isometric (icosahedral), not enveloped, 30 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 five putative products, including a polymerase, a 40-41 kDa coat protein translated from the larger of two subgenomic RNAs and two other products translated from the smaller subgenomic. The structural organization (i.e. number and order of genes) is virtually identical to that of members of the genus
Tombusvirus but the aureusvirus genome is smaller size and there are distinct differences in the amino acid sequence of some of the ORFs.
Type Member Genomic Organization
The RNA is translated into five products:
| 1. | 25 kDa | putative polymerase |
| 2. | 84 kDa | polymerase, produced by readthrough of 1 |
| 3. | 40 kDa | coat protein, translated from subgenomic RNA1 |
| 4. | 27 kDa | movement protein, translated from subgenomic RNA2 |
| 5. | 14 kDa | responsible for symptom severity, translated from subgenomic RNA2 |