microRNA-mediated gene silencing
microRNAs (miRNAs) are a conserved class of small RNAs approximately 22 nucleotides in length. They regulate the expression of a large number of mRNAs in animals and plants through the miRNA-induced silencing complex (miRISC).
The conserved GW182 family of proteins has recently been identified, and its members have been shown to be associated with miRISC and to be required for miRNA-mediated gene silencing.
These proteins have also been localized to processing bodies that are cytoplasmic messenger ribonucleoprotein (mRNP) aggregates containing mRNA decay factors, translational repressors and untranslated mRNAs.
The formation of untranslatable messenger ribonuclear protein particles could be one important mechanism of miRNA-mediated gene silencing.
References
Ding L, Han M. GW182 family proteins are crucial for microRNA-mediated gene silencing. Trends Cell Biol. 2007 Aug;17(8):411-6. PMID: #17766119#