Mitochondrial inner membrane lipid pool and electron transport chain complexes I–III (IMM lipid-ETC complex)

The mitochondrial inner membrane (IMM) lipid pool, specifically the phospholipid cardiolipin, and its interaction with electron transport chain (ETC) complexes I–III form a critical functional unit for cellular energy production (Birk et al., 2013, British Journal of Pharmacology). Cardiolipin acts as a structural scaffold that organizes individual ETC complexes into supercomplexes, which facilitates efficient electron transfer and minimizes the leakage of electrons that leads to oxidative stress (Paradies et al., 2014, Advances in Bioscience and Biotechnology). In various pathological states, cardiolipin is susceptible to peroxidation or depletion, causing the dissociation of these supercomplexes and resulting in mitochondrial dysfunction and reduced ATP synthesis (Szeto, 2014, British Journal of Pharmacology). This target system is central to the etiology of primary mitochondrial diseases like Barth syndrome and mitochondrial myopathy, as well as secondary dysfunction in cardiovascular and neurodegenerative conditions (Chavez et al., 2020, Journal of the American Heart Association). Therapeutic agents such as elamipretide (SS-31) target this system by binding to cardiolipin, thereby stabilizing the IMM and restoring the optimal activity of complexes I and III (Allen et al., 2020, Neurotherapeutics). By preserving mitochondrial structural integrity, these interventions aim to improve bioenergetic capacity and reduce the production of damaging reactive oxygen species (Chatterjee et al., 2016, Journal of Biological Chemistry).

Other names

Inner mitochondrial membrane lipid-protein complexCardiolipin-electron transport chain interfaceMitochondrial respiratory supercomplexesSS-31 target siteCardiolipin-complex I/III association

Stabilization of cardiolipin within the inner mitochondrial membrane to promote the structural integrity of cristae and optimize the assembly and efficiency of electron transport chain supercomplexes.