RNA Interference

RNA interference (RNAi) is a biological process in which RNA molecules inhibit gene expression or translation, by neutralizing targeted mRNA molecules. Initial applications of RNA interference include managing pests and diseases caused by bacteria, fungi and viruses, for improving crop yield, or to generate plants with novel traits (e.g. delayed ripening of Flavr Savr tomato).

Double-stranded RNA-mediated interference (RNAi) is a simple and rapid method of silencing gene expression in a range of organisms.

Two steps of RNAi: The first step involves degradation of dsRNA into small interfering RNAs (siRNAs), 21 to 25 nucleotides long, by an RNase III-like activity. In the second step, the siRNAs join an RNase complex, RISC (RNA-induced silencing complex), which acts on the cognate mRNA and effectively “silence” it.