RNA-induced silencing complex

The RNA - induced silencing complex (RISC ), a complex of RNA and proteins. When RNA is a small interfering RNA ( siRNA) or microRNA (miRNA ) and for the protein content by proteins of the Argonaute family, sometimes another partner.

The RISC function is to reduce off the production of specific proteins ( gene knockout ) or ( gene knockdown ), by degrading the mRNA encoding for these proteins or inhibits their translation. The siRNAs / miRNAs are only about 18-24 nt long, but this brings sufficient specificity. They are substantially complementary to the target mRNA, in providing the antisense strand of the target mRNA and siRNA represents the miRNA binds to the corresponding mRNA, which is then decomposed by activation of the Argonaute protein which acts as a ribonuclease. This will reduce the amount available at a specific mRNA, so that the corresponding protein can no longer be produced only in small amounts or at all. So you could say that the information transport is inhibited. Here, the RNA -protein complex acts as an enzyme, that can repeatedly absorb and degrade mRNAs and in this way reduce the effectiveness of a gene or off.