Notes on Genus: Partitivirus

icosahedra

Type member: Atkinsonella hypoxylon virus

Contents

Members of this Genus
General Description
Morphology
Electron Micrograph
Genome
Genus Genomic Organization
Genome Map
Type Member Genomic Organization
All Known Sequences
Curated Sequences

General Description

This is now the only mycovirus genus in the family Partitiviridae. The name is from the Latin partitus, meaning "divided". Similar viruses of fungi with four genomic components are placed in the genus Chrysovirus (family Chrysoviridae). Some sequences with high similarity to partitiviruses have now been isolated from plants; it is not yet clear whether these are genuine plant pathogens, or whether they have been isolated from a parasitic fungus within the plant.

Morphology

Virions isometric (icosahedral), not enveloped, 30-35 nm in diameter.

Genome

Bipartite, linear, double stranded RNA. The segments are unrelated, separately encapsidated, and 1.4-2.2 kb in size. Additional segments of satellite or defective dsRNA may also be present.

Genus Genomic Organization

The segments are monocistronic and similar in size. RNA1 (the slightly larger segment) encodes an RNA-dependent RNA polymerase (77-86 kDa in currently sequenced members), while RNA2 encodes the coat protein (57-76 kDa in currently sequenced members).

Type Member Genomic Organization