Notes on Family: Astroviridae
This family consists of a viruses that cause gastro-intestinal infections of vertebrates. A proprotion of the spherical virions have a distinct star-shaped appearance (Greek astron
= star) and there are two or three major coat proteins.
Virions isometric (icosahedral), not enveloped, 28-30 nm in diameter, 10% of which have a distinctive 5- or 6-pointed star shape.
Monopartite positive sense single-stranded RNA 6.8-7.9 kb in length with a 3'-polyA tail. The non-structural proteins are encoded by two ORFs that are expressed as one by ribosomal frameshift. The coat protein precursor is towards the 3'-end of the genome and is translated from a subgenomic RNA.
Genera in the Family