Now, what about Small RNA? Well small RNA is basically a constituent of this biological molecule found in a cytoplasm of our cells known as the signal recognition particle. Now remember from biology the signal recognition particle is this complex that binds onto the protein that synthesize polypeptide chain and then brings it to its final destination be it in the cell or outside of cell. So the small RNA molecule helps form the signal recognition particle that directs the synthesized protein to their intracellular or extracellular final destination. Let's move on to small interfering RNA molecules or siRNA molecules. And what these molecules do is they essentially bind onto the mRNA molecule and they stimulate the breakdown, the degradation of the messenger RNA molecule.