A human, ATP-independent, RISC assembly machine fueled by pre-miRNA.

ABSTRACT: RNA interference (RNAi) is mediated by RNA-induced silencing complexes (RISCs), which are guided by microRNAs (miRNAs) or short interfering RNAs (siRNAs) to cognate RNA targets. In humans, the catalytic engine of RISC is a ribonucleoprotein formed by the Argonaute2 (Ago2) protein and either miRNA (miRNP) or siRNA (siRNP). The Dicer nuclease produces mature miRNAs and siRNAs from pre-miRNAs and double-stranded RNA (dsRNA), respectively, and associates with Ago2. Here, we studied the assembly of human RISC by presenting pre-miRNA to immunopurified complexes that contain Ago2, Dicer, and TRBP. Mature miRNAs were produced in an ATP-independent manner and guided specific cleavage of cognate RNA targets in a pattern that is typical of RISC. This de novo formed RISC activity dissociated from Dice

SUBMITTER: Maniataki E 

PROVIDER: S-EPMC1315402 | biostudies-literature | 2005 Dec

REPOSITORIES: biostudies-literature