Cytochrome c, somatic (CYCS)

Cytochrome c, somatic (CYCS) is a highly conserved, small heme protein located in the mitochondrial intermembrane space, where it is essential for electron transport during cellular respiration[1][2][3][4]. It transfers electrons between Complex III (cytochrome bc1) and Complex IV (cytochrome c oxidase), enabling ATP synthesis[1][2]. Cytochrome c also has a pivotal signaling role in apoptosis; upon mitochondrial membrane permeabilization, it is released into the cytosol, where it binds Apaf-1 and triggers caspase activation, leading to programmed cell death[1][2]. Apart from its canonical roles, cytochrome c may act as an antioxidative enzyme and participate in the cellular response to oxidative stress[1]. Mutations in CYCS have been linked with inherited platelet disorders such as Thrombocytopenia 4[2][3]. While not a direct drug target in approved therapies, its functions and regulations are central to mechanisms of a broad range of diseases, especially those involving defective apoptosis or mitochondrial dysfunction[1][2][4].

Other names

Cytochrome cCYCHCSTHC4

Agents that cause mitochondrial outer membrane permeabilization promote cytochrome c release, triggering caspase activation and apoptosis[1][2]. Some antioxidants or pro-oxidant therapies may influence cytochrome c-related pathways.