RNA Interference (RNAi)

RNA interference (RNAi) is a phenomenon by which the expression of double stranded RNA (dsRNA) specifically stimulates a cellular process that reduces gene expression in a sequence specific manner. Small synthetic RNA, termed small interfering RNAs (siRNA), which are typically 21-28 nucleotides in length, can induce RNAi and knockdown gene expression in mammalian cells without inducing an antiviral response. Biochemical studies have elucidated the mechanism of RNAi. Double stranded RNA is processed by an enzyme known as Dicer resulting in the production of siRNA molecules. These molecules are then able to form a multi-protein siRNA complex, known as the RNA-induced Silencing Complex (RISC). The RISC/siRNA complex catalyzes the cleavage and degradation of the complement mRNA molecules.
The use of RNAi applications, including small interfering RNA, to reduce cellular gene expression appears to have significant advantages over other approaches for targeted gene regulation. The potency of siRNA molecules, sequence-specific design, and ability of siRNAs to be re-used to guide mRNA degradation in cells bears a significant advantage over anti-sense oligonucleotides and ribozyme-stem approaches. Well-designed and functional siRNAs are capable of effectively bypassing the interferon response in order to induce specific post-transcriptional gene silencing or RNAi in vitro and in vivo. Altogen Custom Services offer stable cell line generation and RNAi gene silencing services. The capability of siRNAs to mediate post-transcriptional gene silencing in mammalian cells and tissues, as well as its successful use to prevent expression of target mRNA has recently led to the development of a new methodology for novel drug discovery. Several pharmaceutical and biotechnology companies are currently investigating the possible use of synthetic siRNA for inducing RNAi in vivo, its use in animal models, and in RNAi-based therapeutics. Small RNA molecules, such as siRNA, shRNA, and microRNA have been regarded as potential therapeutic agents to target multiple misregulated cellular processes therefore it is theoretically possible that RNAi can be utilized to treat any disease associated with overexpression of specific genes. In fact, there are many reports in the literature that address the potential therapeutic application of RNAi to specifically target genes involved in multiple diseases including various forms of cancer, Alzheimer’s, and a number of inflammatory and virally-associated diseases.