Notes on Genus: Quadrivirus
icosahedra
Type member: Rosellinia necatrix quadrivirus 1
Contents
General Description
The genus
Quadrivirus is the only genus in the family
Quadriviridae. It is named because the genome has four segments.
Morphology
Virions isometric (icosahedral), not enveloped, about 48 nm in diameter.
Genome
Quadripartite, linear double-stranded RNA, with segments ranging in size from 3.7 to 4.9 kbp. A terminal sequence of seven 5’- and fourteen 3’-nucleotides is strictly conserved in all segments.
Genus Genomic Organization
There are four RNAs, each encoding a single protein.
Type Member Genomic Organization
- RNA1 (4.9 kbp) encodes a protein of 178 kDa (function unknown)
- RNA2 (4.4 kbp) encodes a stuctural protein of 147 kDa
- RNA3 (4.1 kbp) encodes a polymerase of 147 kDa
- RNA4 (3.7kbp) encodes a second structural protein of 113 kDa