miRISC is a multi-protein assembly that identifies mRNAs targeted for reppression using microRNAs (miRNAs). In vitro and in living cells, 29576456 demonstrated that two core protein components of human miRISC, Argonaute2 (Ago2) and TNRC6B, condense into phase-separated droplets.
Formation, Composition & dynamics (Assembly and disassembly)
The glycine/tryptophan (GW)-rich domain of TNRC6B interacts multivalently with three equally spaced tryptophan-binding pockets in the Ago2 PIWI domain, promoting miRISC phase separation. Deadenylation factors are recruited and target RNAs are sequestered from the bulk solution by miRISC droplets produced in vitro. The rapid deadenylation of target RNAs coupled to Ago2 coincides with the condensation of miRISC (29576456).
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