RNA Interference

Abstract

A revolution has recently swept through biology called RNA interference. RNAi serves as an umbrella term, encompassing several phenomena discovered in a diversity of eukaryotes, all of which are mediated by short RNA species. RNAi has been implicated in regulating gene expression by several mechanisms, from transcriptional silencing to mRNA degradation and translational repression. The central role of RNAi processes in gene expression is underscored by its strong conservation across almost all eukaryotes, from plants to fungi to mammals. This review will focus on the discovery of the classical RNAi pathway before considering the molecular details of this pathway. RNAi will then be viewed from a broader perspective, by examining other small RNA directed pathways in a variety of organisms. One pathway in particular will receive ample attention, that of the endogenous microRNA genes, a class of small RNAs that has arisen in multicellular plants and animals. Finally, the adoption of RNAi as a powerful technology will be discussed, including prospects for RNAi-based therapeutic applications.