RNA interference: genetic wand and genetic watchdog

In many species, introduction of double-stranded RNA (dsRNA) induces potent and specific gene silencing, a phenomenon called RNA interference or RNAi. The apparently widespread nature of RNAi in eukaryotes, ranging from trypa nosome to mouse, has sparked great interest from both applied and fundament al standpoints, Here we review the technical improvements being made to inc rease the experimental potential of this technique. We also discuss recent advances in uncovering the proteins that act during the RNAi process, disco veries that have revealed enticing links between transposition, transgene s ilencing and RNAi.