Figure 3.

Summary of current strategies for mitochondrial targeting. (A) attachment of lipophilic cations such as triphenylphosphonium to small molecules or nanocarriers for targeting to the mitochondria; (B) Mitochondrial targeting Szeto-Schiller (SS) peptides containing an aromatic-cationic sequence motif selectively partition into the inner mitochondrial membrane independent of the mitochondrial membrane potential; (C) A dicationic mitochondriotropic compound, dequalinium chloride, self-assembles and forms vesicle-like aggregates called DQAsomes. These vesicles are taken up by endocytosis, fuse with the mitochondrial outer membrane and enter to the mitochondrial matrix via the mitochondrial protein import machinery; (D) MITO-porter is a liposome-based carrier that fuses with the mitochondrial membrane and releases its cargo to the intra-mitochondrial compartment; (E) Mitochondrial targeted signal peptides attached to non-mitochondrial proteins create a chimeric protein taken up by the mitochondrial matrix via the mitochondrial protein import machinery. Cargo consisting of a drug or nucleic acid attached to this chimeric protein can be selectively transferred to mitochondria.