Subfamily: Comovirinae

Genus: Fabavirus

 

Distinguishing features

Fabaviruses have bipartite genomes encapsidated by two capsid proteins (CP) and are transmitted by aphids.

Virion

See discussion under family description.

Genome organisation and replication

The genomic organization of fabaviruses is similar to that of comoviruses. Similar to comoviruses, RNA2 encodes two overlapping polyproteins with the N-terminal protein playing a role in the replication of RNA2 and the overlapping movement protein being synthesized through initiation at the second AUG codon (Lin et al., 2014). The movement protein was also confirmed to be a structural component of the tubular structures that traverse the cell wall (Liu et al., 2011) (Figure 3.Secoviridae). The cleavage of polyproteins is presumed to be similar to that of comoviruses but this has not been investigated in detail.

Biology

Fabaviruses have wide host ranges among dicotyledonous plants and some families of monocotyledonous plants. Symptoms are ringspots, mottling, mosaic, distortion, wilting and apical necrosis. In nature, fabaviruses are transmitted by aphids in a non-persistent manner.

Species demarcation criteria

See discussion under family description