%0 Journal Article %A Tavantzis, S. M. %A Bandy, B. P. %T Properties of a Mycovirus from Rhizoctonia solani and Its Virion-associated RNA Polymerase %D 1988 %J Journal of General Virology, %V 69 %N 7 %P 1465-1477 %@ 1465-2099 %R https://doi.org/10.1099/0022-1317-69-7-1465 %K Rhizoctonia solani %K RNA polymerase %K mycovirus %I Microbiology Society, %X Summary Isometric virus particles, 33 nm in diameter, were purified to apparent homogeneity from a dsRNA-containing isolate (Rhs 717) of anastomosis group 2 of the basidiomycete Rhizoctonia solani. The dsRNA segments isolated from purified particles had the same M r (1.5 × 106 and 1.4 × 106) as those isolated directly from mycelial tissue of Rhs 717. Purified virus particles had a buoyant density of 1.37 g/ml in CsCl, and an A 260/A 280 ratio of 1.43. The melting curve of the mixture of dsRNA segments from Rhs 717 particles had a sharp thermal transition with a melting temperature of 95 °C in standard saline citrate buffer. The RNA polymerase activity associated with the purified virus was characterized. Enzyme activity was dependent on the presence of Mg2+ and was insensitive to actinomycin D. Virus particles and RNA polymerase activity cosedimented as a single peak in isopycnic CsCl gradients. The major reaction products were two dsRNA segments of M r 1.5 × 106 and 1.4 × 106, which corresponded to those of the two viral dsRNAs. The [32P]UMP-labelled products hybridized to the two viral dsRNAs. The RNA synthesized in vitro remained in association with virus particles subjected to agarose gel electrophoresis. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-69-7-1465