Mitochondrial oxidative phosphorylation system (OXPHOS) (OXPHOS)

The mitochondrial oxidative phosphorylation (OXPHOS) system is the primary energy-generating machinery in eukaryotic cells, consisting of five multi-subunit protein complexes (Complexes I-V) located in the inner mitochondrial membrane (StatPearls, 2023). It couples the transfer of electrons from electron donors (NADH and FADH2) to oxygen with the pumping of protons to create an electrochemical gradient, which ultimately drives the synthesis of ATP by ATP synthase (NCBI, 2022). Beyond energy production, this machinery plays critical roles in regulating cellular redox state, reactive oxygen species (ROS) signaling, and the initiation of apoptosis (Nature Reviews Molecular Cell Biology, 2020). Dysregulation of OXPHOS is implicated in a wide range of pathologies, including primary mitochondrial disorders, neurodegenerative diseases like Parkinson's, and metabolic syndromes (PubMed, 2021). In oncology, certain cancers exhibit a high dependency on OXPHOS, making specific components like Complex I attractive therapeutic targets for small-molecule inhibitors such as IACS-010759 (Nature Medicine, 2018). However, targeting these enzymes requires careful management of systemic toxicity, as they are essential for the function of high-energy-demand organs like the heart and brain (Journal of Clinical Investigation, 2017).

Other names

Electron transport chainRespiratory chainMitochondrial respiratory chainMitochondrial respiratory chain complexes

Inhibition of electron transport chain complexes (I-IV), uncoupling of oxidative phosphorylation, and inhibition of ATP synthase (Complex V) to modulate cellular energy levels and redox state.