Minimal RISC (miRNA) pre-RISC (miRNA) Removal of miRNA passenger strand A short double-stranded RNA is passed from Dicer to an Argonaute and rendered single-stranded by removal and loss of the passenger strand. All Argonautes (AGO1, AGO2, AGO3, AGO4) can remove the passenger strand without cleaving it and most miRNAs are processed in this way. AGO2 can cleave the passenger strand of a subset of miRNAs that have no mismatches in the central region (Shin 2008). <br>RNA helicase A is associated with the RISC loading complex can facilitate removal of the passenger strand.<br>The mechanism that selects which strand is retained as the guide RNA is not well understood in humans. Overhanging nucleotides and strength of base-pairing at each end of the input duplex are observed to influence strand selection.<br>Argonaute proteins directly or indirectly bind many other proteins and appear to be present in more than one distinct complex. Authored: Gopinathrao, G, May, B, 2007-11-18 23:55:40 Edited: May, B, 2009-06-10 Pubmed15284456 Pubmed16271386 Pubmed16357216 Pubmed17531811 Pubmed17932509 Pubmed18178619 Pubmed18728384 Pubmed18782830 Pubmed18842624 Pubmed19401777 Pubmed19966796 Reactome Database ID Release 43210805 Reactome, http://www.reactome.org ReactomeREACT_118810 Reviewed: Tomari, Y, 2012-02-10