Preadsorption of aniline dimer on the surface of MWCNTs enabled a composite with better morphology, high conductivity, high specific capacitance and long cycling stability to be fabricated.

Cucumber mosaic virus (CMV) is a tripartite RNA virus that can support the replication of satellite RNAs, small molecular parasites of the virus. Satellite RNAs can have a dramatic effect on the helper virus and the host plant in a manner specific to the helper, satellite, and host. Previously, we showed that the Sny-CMV strain is not able to support the replication of the WL1 satellite RNA in zucchini squash and that this phenotype maps to RNA 1. In the present study, we use recombinant cDNA clones of Fny- and Sny-CMV RNA 1 and a site-directed mutant of Fny-CMV RNA 1 to demonstrate that the inability to support WL1 satellite RNA maps to a single amino acid at residue 978 in the 1a protein, proximal to the helicase domain VI. Support of satellite RNA in whole plants and in protoplasts of zucchini squash is analyzed.

The presence of cucumber mosaic virus (CMV) satellite RNA usually reduces the yield of accumulated helper virus, although more so in solanaceous than in cucurbit hosts. The accumulation of viral RNA and viral-encoded proteins of two strains of CMV (Fny- and Sny-) known to differ in their ability to support satellite RNA in zucchini squash was examined in squash and tobacco to determine the effect of satellite RNA on the accumulation of viral-associated components. In the absence of satellite RNA, Fny- and Sny-CMV showed similar levels of accumulation of RNA at 7 days postinoculation (p.i.), but by 14 days p.i. the Fny-CMV RNAs accumulated to lower levels than did both strains at 7 days p.i., in either host. The levels of accumulated Sny-CMV-encoded proteins were higher than those encoded by Fny-CMV in tobacco, but not squash plants, at 7 days p.i. At 14 days p.i., for Fny-CMV vs Sny-CMV, there were differences in the levels of accumulation of most CMV-encoded proteins in both hosts, more exacerbated in tobacco vs squash. The effect of satellite RNA was to intensify these differences; that is, by 7 days p.i., satellite RNA reduced the accumulation of Fny-CMV RNAs 1 and 2 and their encoded proteins in both tobacco and squash but had little or no effect on the accumulation of Sny-CMV RNAs or encoded proteins. By 14 days p.i., the levels of accumulation of all Fny-CMV RNAs and encoded proteins were severely reduced in both hosts, and the levels of accumulation of Sny-CMV RNAs 1 and 2 and their encoded proteins were also reduced in tobacco, but not squash. Sny-CMV did not support satellite RNA accumulation in squash plants or protoplasts. Satellite RNA did not appear to have a direct effect on the movement of either CMV strain. Rather, accumulation studies in tobacco protoplasts indicated that the difference in response of Fny-CMV vs Sny-CMV to satellite RNA in tobacco was due to the extent to which satellite RNA affected the levels of RNA 1, and to a lesser extent RNA 2, and their encoded proteins, 1a and 2a, both components of the CMV replicase.

The differential rate of systemic symptom induction in zucchini squash by the Fny- and Sny-strains of cucumber mosaic virus (CMV) previously was mapped to RNA 1, which encodes a protein (1a) involved in virus replication. Examination of the kinetics of accumulation of the RNAs and the four encoded proteins in the inoculated cotyledons showed that the Fny-CMV-associated products generally appeared earlier then the Sny-CMV-associated products. In the systemically infected leaves, this difference was magnified, with a 2-day delay in the appearance of the Sny-CMV RNAs and encoded proteins. However, both Fny-CMV and Sny-CMV RNAs showed similar kinetics of RNA, 2a, 3a, and coat protein accumulation in protoplasts prepared from zucchini squash cotyledons. These data indicate that the differential rate of systemic symptom development was due to a difference in the rate of movement rather than the rate of replication. This was confirmed by a leaf-detachment assay, which showed a difference in the rate of systemic movement by Fny-CMV vs Sny-CMV, and by leaf-press blot hybridization of the inoculated cotyledons at different days postinoculation, which showed a difference in the rate of cell-to-cell movement by the two strains of CMV. Taken together, these data show that the rates of cell-to-cell and long-distance movement can be regulated by sequences in CMV RNA 1, previously thought to be involved only in virus replication.