Fig. 1

Schematic representation of the various mitochondrial-transfer modes utilized between donor cells and damaged cells with dysfunctional mitochondria. A Extracellular vesicles (EVs) can convey mtDNA or fragments of mitochondria; though less well documented, microvesicles are suggested to contain entire mitochondria. B Cx43-mediated gap junctions serve at the cell–cell junction to enable mitochondrial transfer. Tunneling nanotubes (TNTs) are actin-dependent cytoskeletal protrusions that also serve as cytoplasmic bridges between cells. Miro1 regulates the transport of mitochondria across TNTs. C. Cell fusion enables sharing of cytoplasmic contents during either transient or permanent fusion of the plasma membranes of two cells