Notes on Genus: Quadrivirus

icosahedra
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