The 3' terminal sequence of a human astrovirus

We have determined the sequence for 1,000 bases from the 3' terminus of a human astrovirus serotype 1 isolated in Newcastle. This is the first sequence reported for a representative of this virus family. We find one open reading frame which terminates 83 bases from a poly A tail. The 3' non-coding-region has similarities to some picornavirus termini. However the amino acids specified by the coding region have no significant homology to the picornavirus protein 3D, encoded at the 3' terminus of these viruses. Northern blot analysis of intracellular virus-specific RNAs revealed one size of transcript which corresponded to full-length virus RNA. Available data thus indicate that astroviruses may resemble picornaviruses in replication strategy.