Maintenance of redox homeostasis by hypoxia-inducible factors.

Oxidative phosphorylation enables cells to generate the large amounts of ATP required for development and maintenance of multicellular organisms. However, under conditions of reduced O2 availability, electron transport becomes less efficient, leading to increased generation of superoxide anions. Hypoxia-inducible factors switch cells from oxidative to glycolytic metabolism, to reduce mitochondrial superoxide generation, and increase the synthesis of NADPH and glutathione, in order to maintain redox homeostasis under hypoxic conditions.