Induction of RNA interference using short interfering RNA expression vectors in cell culture and animal systems

RNA interference, (RNAi) is a phenomenon by which the introduction of double stranded RNA (dsRNA) into cells induces targeted degradation of RNA molecules with homologous sequences. In the laboratory, RNAi has become a valuable tool for analysis of gene function through suppression of specific gene products. In addition, RNAi has shown great promise for use in therapeutic strategies designed to suppress the expression of pathogenic genes. In this review, viral expression and animal model systems that indicate the potential benefits of RNAi will be discussed. The major obstacle for the use of short interfering RNA in a laboratory or clinical setting is the need for efficient and sustained delivery of dsRNA to mammalian cells. Here, current methods that are being used to induce RNAi, both in cultured cells and in animal models, will be described with a focus on some of the most promising applications.