Characterization of endogenous human Argonautes and their miRNA partners in RNA silencing.

Small RNAs triggering RNA silencing are loaded onto Argonautes and then sequence-specifically guide them to target transcripts. Epitope-tagged human Argonautes (hAgo1, hAgo2, hAgo3, and hAgo4) are associated with siRNAs and miRNAs, but only epitope-tagged hAgo2 has been shown to have Slicer activity. Contrarily, how endogenous hAgos behave in respect to small RNA association and target RNA destruction has remained unclear. Recently, we produced monoclonal antibodies for individual hAgos and characterized small RNAs specifically associated with hAgo2 and hAgo3 endogenously expressed in Jurkat cells.

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