Characterization of RNA polymerase associated with rice ragged stunt virus.

The RNA polymerase associated with rice ragged stunt virus (RRSV) was characterized. Activity was optimum at 35-40 degrees in 0.1 MTris-HC1 (pH 8.5) and 6-8 mMMgCl2. S-Adenosyl-L-methionine stimulated the activity about 5- to 6-fold. It was also stimulated in the presence of chymotrypsin (200 micrograms/ml). The molecular weights of RNAs synthesized in vitro were calculated to be about half those of the respective genome segments. The synthesized RNAs hybridized to the genome RNAs, and the hybrids migrated identically to the genome RNAs in PAGE. These results indicate that RRSV particles transcribe full-length copies of the genome RNAs. The characteristics of the polymerase are discussed in relation to those of other members of the Reoviridae.