RNA interference

RNA interference is a biological process in which RNA molecules inhibit gene expression or translation. Andrew Fire and Craig Mello shared the 2006 Nobel Prize in Physiology or Medicine for their work on RNA interference in the nematode worm Caenorhabditis elegans.

About RNA interference in brief

RNA interference is a biological process in which RNA molecules inhibit gene expression or translation, by neutralizing targeted mRNA molecules. Andrew Fire and Craig Mello shared the 2006 Nobel Prize in Physiology or Medicine for their work on RNA interference in the nematode worm Caenorhabditis elegans. Since the discovery of RNAi and its regulatory potentials, it has become evident that RNAi has immense potential in suppression of desired genes. RNAi is a valuable research tool, both in cell culture and in living organisms, because synthetic dsRNA introduced into cells can selectively and robustly induce suppression of specific genes of interest. It can also be used for large-scale screens that systematically shut down each gene in the cell, which can help to identify the components necessary for a particular cellular process or an event such as cell division. The pathway is also used as a practical tool in biotechnology, medicine and insecticides. It is initiated by the enzyme Dicer, which cleaves long double-stranded RNA molecules into short double- Stranded fragments of ~21 nucleotide siRNAs. Exogenous ds RNA initiates RNAi by activating the ribonuclease protein Dicer,. which binds and cleaves double-Stranded RNAs in plants, or short hairpin RNAs in humans, to producedouble-strander fragments of 20–25 pairs with a 3’nucleotide overhang at the 3′ end. Bioinformatics studies suggest multiple organisms suggest this length maximizes target-gene specificity and minimizes non-specific effects on the genomes of genomes of this type of organism.

These small interfering RNAs are then separated into single strands and integrated into an active RISC-Loading Complex, by 10-fold affinity to tetramerization, which increases the binding affinity to T-R2. The RISC is crucial to unite the RLC-2 and RISC ATA-binding protein-associated factor 11 (RISC TATA) to unite 11-fold binding protein-ATA- binding protein 11 (TATA) and convert the siRNA to RISC. In some organisms, this process spreads systemically, despite the initially limited molar concentrations of siRNA. The most well-studied outcome is post-transcriptional gene silencing, which occurs when the guide strand pairing with a complementary sequence in a messenger RNA molecule and induces cleavage by Argonaute 2, the catalytic component of the RISC, in the cytoplasm. The passenger strand is degraded and the guide strands are incorporated into the RNA-induced silencing complex. The RNAi pathway is found in many eukaryotes, including animals, and is initiated in the nucleus, where they interact with a catalytic RISC component argonaute. When the dsRNAs are exogenous, the RNA is imported directly into the cy toplasm and cleaved to short fragments by Dicer. The initiating ds RNAs can be endogenous, as in pre-microRNAs expressed from RNA-coding genes in the genome. The primary transcripts from such genes are first processed to form the characteristic stem-loop structure of pre-miRNA.

Related posts:

CRISPR gene editing Cell nucleus West Nile virus RNA vaccine