Conserved terminal sequences of rice ragged stunt virus genomic RNA.

The 5'- and 3'-terminal nucleotide sequences of the dsRNA genome segments of rice ragged stunt virus (RRSV), a member of the plant Reoviridae, were determined and compared with those published for other viruses in this family. The 5'- and 3'-terminal regions of the RRSV plus strand RNA from all genome segments were found to have the same conserved hexanucleotide (5' GAUAAA---) and tetranucleotide (---GUGC 3') sequences, respectively. These conserved terminal sequences were different from those found in viruses in the Phytoreovirus and Fijivirus genera. This result confirms that, as already suggested, RRSV should be placed in a third genus.