VIRION
No true capsid. The dsRNA genome is encapsulated along with the viral replicase enzyme within host-derived lipid pleomorphic vesicles (50-80nm in diameter).
GENOME
Linear dsRNA genome of 9-13kb, encodes one or two ORFs (ORFB, and eventually ORFA). The 3'end is polyadenylated. The genome only encodes non-structural proteins.
May also contain additional satellite dsRNAs.
GENE EXPRESSION
ORFB (and if present, ORFA) encodes a polyprotein that is proteolytically processed.
REPLICATION
CYTOPLASMIC
Poorly understood. The virus never budds out of its host and probably replicates in lipid pleomorphic vesicles. Transmission dependent on cell to cell cytoplasmic exchange, and hyphal anastomosis.