RNA Interference (RNAi) is a process by which the expression of double stranded RNA specifically stimulate a cell process that reduce gene expressions in a sequence specific manner. Small synthetic RNA, usually termed small interfering RNAs (siRNA) is typically 21-28 nucleotides long, can induce RNAi and knockdown mRNA expression of genes in mammalian cells without an antiviral response. Biochemical research have elucidated the mechanisms of RNAi. Double-stranded RNA is processed by enzyme (known as Dicer) resulting in production of the siRNA molecules. Those molecules can form a multi protein siRNA complex (known as the RNA-induced Silencing Complex (RISC)). The RISC/siRNA complexes catalyzes cleavages and degradation of complement mRNA molecules.
Greater understanding of how RNAi works is an excellent research tool that experts have utilized in the development of pharmaceuticals as well as therapies in medicine, offering researchers the ability to literally stop specific gene activity in its track. This results in offering researchers large amounts of information about specific gene functions in cellular pathways. Before RNAi was discovered, these process were extremely difficult to understand and analyze, and such studies often took months. Today, by literally capturing RNAi, researchers can effectively silence specific genes in a relatively quick and easy process, enabling them to focus on techniques that will expose the behavior and development of specific genes that play a large role in normal as well as a disease processes.
The use of RNAi applications (including small interfering RNA transfection) to reduce gene expression appear to have major advantages over other methods for targeting gene regulations. The potency of siRNAs, sequence specific design, and abilities of siRNAs to be reused to guide mRNA’s degradation in a cell bears significant advantages over antisense oligonucleotides and ribozyme approaches.
Well designed functional siRNA are capable to effectively bypass the interferon response – in order to induce specific posttranscriptional gene silencing (or RNAi in vitro and in vivo).