THE MOLECULAR-BIOLOGY OF ASTROVIRUSES

Astroviruses (genus Astrovirus) are assigned to a newly established vi rus family, the Astroviridae. The molecular biology of these agents re veals many features unique amongst the non-enveloped animal viruses an d resembles that of members of certain plant virus families. In partic ular, their possession of a serine protease and use of ribosomal frame shifting to express the RNA polymerase are similar to the luteoviruses . Many aspects of the astrovirus replication strategy are still unclea r, but replication may involve a nuclear step and non-structural prote ins may influence host cell range.