RISC

RISC, the cytoplasmic RNA-induced silencing complex, is a complex of RNA and proteins that process pre-microRNAs into mature microRNAs (miRNAs). RISC is activated in an ATP-dependent manner and triggers sequence-specific degradation of the target mRNA. In this process, only the antisense strand is crucial for homologous base pairing with the endogenous target mRNA and subsequent enzymatic degradation.

The RNA of the RISC complex is a small interfering RNA (siRNA) or a microRNA (miRNA). The protein portion is Argonaute family proteins and other proteins including protein kinase RNA activator (PACT), transactivation response RNA binding protein (TRBP) and Dicer. The function of RISC is to eliminate (gene knockout) or decrease (gene knockdown) the production of specific proteins by degrading the mRNA encoding these proteins or inhibiting their translation. This process is known as RNA interference.

1. Dana H et al (2017) Molecular Mechanisms and Biological Functions of siRNA. Int J Biomed Sci 13: 48-57.