Mechanisms of RNA loading into exosomes.
Upon fusion of multivesicular bodies (MVBs) with the plasma membrane, intraluminal vesicles (ILVs) are released into the extracellular space as exosomes. Since the lipid composition of the exosomal membrane resembles that of raft microdomains, the inward budding process involves the raft-like region of the MVB limiting membrane. Although published research suggests that cellular RNAs may be selectively sorted into exosomes, the molecular mechanisms remain elusive. In this review, we suggest that there is a continuous interaction of cellular RNAs with the outer (cytoplasmic) surface of MVBs and that the selection for incorporation of these RNAs into ILVs is based on their affinity to the raft-like region in the outer layer of the MVB membrane.
Department of Biotechnology and Molecular Biology, University of Opole, Kominka 6, 45-032 Opole, Poland.
Teresa
T
Janas
Alnylam Pharmaceuticals, 300 Third Street, Cambridge, MA 02142, USA.
Maja M
MM
Janas
Department of Biotechnology and Molecular Biology, University of Opole, Kominka 6, 45-032 Opole, Poland.
Karolina
K
Sapoń
Department of Biotechnology and Molecular Biology, University of Opole, Kominka 6, 45-032 Opole, Poland; Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309, USA.
Tadeusz
T
Janas
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D055354:Exosomes / Q000378:metabolism*; D006801:Humans; D008563:Membrane Lipids / Q000378:metabolism; D021962:Membrane Microdomains / Q000378:metabolism; D008954:Models, Biological; D057146:Multivesicular Bodies / Q000378:metabolism*; D012313:RNA / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism
D008563:Membrane Lipids; D016601:RNA-Binding Proteins; D012313:RNA
Ceramide; Exosomes; Intraluminal vesicles; Membrane; MicroRNA; RNA; Rafts