The role of Dicer's helicase domain is enigmatic, but in vivo it is required for processing certain endogenous siRNA, but not miRNA. By using Caenorhabditis elegans extracts or purified Drosophila Dicer-2 we compared activities of wild-type enzymes and those containing mutations in the helicase domain. We found the helicase domain was essential for cleaving dsRNA with blunt or 5'-overhanging te...

Small circular double-stranded RNAs (dsRNAs) were synthesized. The structural analysis by atomic force microscopy gave direct images for the interpretation of the structural strain present in circular dsRNAs. Finally, we demonstrated that circular dsRNA caused RNAi effect in cells.

In RNA-mediated interference (RNAi), double-stranded RNAs (dsRNAs) target complementary mRNAs for degradation. New work demonstrates that essential chromosomal functions are mediated through RNAi protein components and short RNAs, which alter chromosome function at specific DNA loci via histone modification.

3-Methylquercetin is a natural flavone that powerfully blocks poliovirus replication. This compound inhibits selectively poliovirus RNA synthesis both in infected cells and in cell-free systems. Poliovirus double-stranded RNA (replicative forms) is still made in the presence of this inhibitor, whereas the synthesis of single-stranded RNA and the formation of replicative intermediates are drasti...

Double-stranded RNA can induce the degradation of homologous RNAs in organisms as diverse as protozoa, animals, plants and fungi, resulting in post-transcriptional gene silencing. But in some species, RNA-mediated processes can also lead to translational repression, DNA methylation, heterochromatin formation or DNA elimination. In some situations, amplification of the 'trigger' double-stranded ...

RNA interference (RNAi) by oral delivery of dsRNA in insects has great potential as a tool for integrated pest management (IPM), especially with respect to addressing the need to reduce off-target effect and slow down resistance development to chemical insecticides. Employing the natural association existing between insect and yeast, we developed a novel method to enable the knock down of vital...

The mle(napts) mutation causes temperature-dependent blockade of action potentials resulting from decreased abundance of para-encoded Na+ channels. Although maleless (mle) encodes a double-stranded RNA (dsRNA) helicase, exactly how mle(napts) affects para expression remained uncertain. Here, we show that para transcripts undergo adenosine-to-inosine (A-to-I) RNA editing via a mechanism that app...