Notes on Family: Dicistroviridae



General Description

This family has many of the features of the picornavirus "superfamily" but the established members infect insects and have a genome with two polyproteins (hence the family name, from "dicistron").


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


Monopartite positive sense single-stranded RNA 8.0-10.5 kb in length with a genome-linked protein (VPg) at the 5'-terminus and a 3'-polyA tail.

Genera in the Family

There are two genera that differ in the sequence and structure of the internal ribosome entry site (IRES) at the intergenic region (IGR) between the two ORFs. This is supported by phylogenetic analysis: