Updated FTP location. We prepared BmN4 cell lysates in Co-IP buffer [30 mM HEPES-KOH pH 7.3, 150 mM potassium acetate, 5 mM magnesium acetate, 5 mM dithiothreitol, 0.1% (w/v) NP-40 and cOmplete ULTRA EDTA-free protease inhibitor (Roche)] with and without 1 mM EDTA and conducted immunoprecipitation assays using anti-Ago3 antibody. The reaction was terminated by boiling with SDS sample buffer.