Sequences of all 12 rice dwarf phytoreovirus (RDV) genome segments (S1–S12) have been determined. Each segment has a terminal sequence of six 5′- and four 3′-nucleotides conserved in all segments, and a subterminal segment-specific inverted repeat. RDV S1 to S11 each contain single large open reading frames (ORFs), while S12 has three potential ORFs and specifies three polypeptidesin vitro. The following gene product assignments have been established: S1–S3, S5, S7 and S8 encode structural proteins, and S4, S6 and S9–S12 code for non-structural ones. Data on functions of some of the gene products, and molecular evolution are also presented. These provide a basis for further molecular analysis of RDV.
