Members of this family are insect-infecting viruses that consist of positive single-strand RNA genomes translated into a single polyprotein of ~3000 amino acids long. It encodes helicase, protease and RNA-dependent RNA polymerase enzymes and four structural proteins (VP1–4). The non-envelopedcapsid has an icosahedral T=pseudo3 symmetry and is around 30 nm in diameter. VP1, VP2 and VP3 form the outer portion, with VP4 located internally.[1][3] Genomes are linear and non-segmented, around 8.8-9.7kb in length.[1][3]
Life cycle
Viral replication is cytoplasmic. Entry into the host cell is achieved by attachment to host receptors, which mediates endocytosis. Replication follows the positive stranded RNA virus replication model. Positive stranded RNA virus transcription is the method of transcription. Translation takes place by ribosomal skipping. Insects serve as the natural host.[1][3]
Pathogenicity
Several viruses in this family are economically important because they are highly pathogenic to their honeybee and silkworm hosts, while others (including Dinocampus coccinellae paralysis virus, Nasonia vitripennis virus and Venturia canescens picorna-like virus) appear to cause little or no symptoms.[4]
Taxonomy
The family Iflaviridae contains one genus, Iflavirus, with the following 16 species:[1][5]
