The molecular biology of astroviruses.

Astroviruses (genus Astrovirus) are assigned to a newly established virus family, the Astroviridae. The molecular biology of these agents reveals many features unique amongst the non-enveloped animal viruses and resembles that of members of certain plant virus families. In particular, their possession of a serine protease and use of ribosomal frameshifting to express the RNA polymerase are similar to the luteoviruses. Many aspects of the astrovirus replication strategy are still unclear, but replication may involve a nuclear step and non-structural proteins may influence host cell range.