Notes on Genus: Soymovirus


Type member: Soybean chlorotic mottle virus


General Description

This is one of 7 genera in the family Caulimoviridae, which are distinctive amongst plant viruses in having double-stranded DNA. Members of this genus are those with isometric, rather than bacilliform particles and with 8 open reading frames in the genome. They were previously classified in the Caulimovirus genus, but this now only includes those viruses with 6 or 7 open reading frames. The name is derived from the type member, Soybean chlorotic mottle virus.


Virions isometric, not enveloped, 45-50 nm in diameter with no obvious surface structure. The virion shell is multi-layered.

Virions composed of 16 % nucleic acid.


Monopartite, open circular, double stranded DNA of c.8200 base pairs.

Genus Genomic Organization

Eight potential open reading frames have been identified. The movement protein (1a), coat protein (4), reverse transcriptase (5) and post-trancriptional activator (6) are homologous to those of the genus Caulimovirus, but the other ORFs are thought to function differently.

Type Member Genomic Organization

The proposed ORFs are:
1a    35.6 kDa Movement protein
1b 13.8 kDa
2 23.3 kDa
3 22.5 kDa
4 52.1 kDa Coat protein
5 80.4 kDa Reverse transcriptase
6 53.1 kDa Possible post transcriptional activator
7 17.1 kDa
8 9.6 kDa possible ORF