For the French ships, see French ship Argonaute Argonaute proteins are the catalytic components of the RNA-induced silencing complex (RISC), the protein complex responsible for the gene silencing phenomenon known as RNA interference (RNAi). Argonaute proteins bind small interfering RNA (siRNA) fragments and have endonuclease activity directed against messenger RNA (mRNA) strands that're complementary to their bound siRNA fragment. The proteins are also partially responsible for selection of the… (More on Argonaute)