Notes on Genus: Alphacryptovirus

icosahedra
icosahedra

Type member: White clover cryptic virus 1

Contents

General Description

This is one of 2 plant virus genera in the family Partitiviridae. Both genera have double stranded bipartite RNA genomes, isometric particles, and cause latent infections in plants. The name is from the Greek crypto, meaning "hidden". Members of this genus have smaller particles (30nm) than those of the genus Betacryptovirus and are not serologically related to them.

Morphology

Virions isometric (icosahedral), not enveloped, 30 nm in diameter.

Virions composed of 25% nucleic acid.

Genome

Bipartite, linear, double stranded RNA, typically of about 1.7 and 2.0 kbp.

Genus Genomic Organization

The two RNAs are monocistronic. One encodes the RNA polymerase and the other the coat protein.

Type Member Genomic Organization

  • RNA1 (1955 nt): encodes an RNA polymerase of 73 kDa
  • RNA2 (1708 nt): encodes the coat protein of 54 kDa