Molecular weights of the double-stranded RNAs of cucumber mosaic virus strain S and its associated RNA 5

Abstract

The molecular weights of the double-stranded (ds) RNAs of cucumber mosaic virus (CMV) and CMV-associated RNA 5 (CARNA 5) produced in tobacco plants were calculated from previously published values of the single-stranded (ss) CMV RNAs and CARNA 5. These molecular weights were compared with those of the dsRNAs of Penicillium chrysogenum virus (PcV) and P. stoloniferum virus (PsV), determined by others by means of contour-length measurements. When electrophoresed simultaneously in 2.4% polyacrylamide gels, all dsRNA components were clearly resolved except for dsCMV 1 and dsCMV 2 which coelectrophoresed with dsPcV 2 and dsPcV 3, respectively. A semilogarithmic plot of the molecular weights of the dsRNAs versus their electrophoretic migration distances gave a nonlinear, smoothly curved line which fit most of the points, and thus confirmed the basic validity of the molecular weights used. For the dsRNAs of CMV and CARNA 5, the molecular weights are: dsCMV RNA 1, 2.02 × 10 6; dsCMV RNA 2, 1.78 × 10 6; dsCMV RNA 3, 1.36 × 10 6; dsCMV RNA 4, 0.66 × 10 6; dsCARNA 5, 0.22 × 10 6.