Although extracellular vesicles (EVs) are by far the most studied carriers of extracellular small RNAs involved in cell-to-cell communication, most extracellular small RNAs are actually present as soluble vesicle-free supramolecular complexes. Several proteins have been described as the counterparts of these RNase-protected complexes. Here we describe a method for the purification and analysis of non-vesicular extracellular RNA derived from the conditioned media of mammalian cell culture. Focus on this fraction will increase our understanding on extracellular RNA biology, while serving as a source for biomarker discovery complementary to EVs.
Keywords: Exosomes; Ribonucleoprotein fraction; Sequencing; miRNA; tRNA fragments.