Cytochrome c phosphorylation: Control of mitochondrial electron transport chain flux and apoptosis.

Cytochrome c phosphorylation: Control of mitochondrial electron transport chain flux and apoptosis. Int J Biochem Cell Biol. 2020 Feb 02;:105704 Authors: Kalpage HA, Wan J, Morse PT, Zurek MP, Turner AA, Khobeir A, Yazdi N, Hakim L, Liu J, Vaishnav A, Sanderson TH, Recanati MA, Grossman LI, Lee I, Edwards BFP, Hüttemann M Abstract Cytochrome c (Cytc)1is a cellular life and death decision molecule that regulates cellular energy supply and apoptosis through tissue specific post-translational modifications. Cytc is an electron carrier in the mitochondrial electron transport chain (ETC) and thus central for aerobic energy production. Under conditions of cellular stress, Cytc release from the mitochondria is a committing step for apoptosis, leading to apoptosome formation, caspase activation, and cell death. Recently, Cytc was shown to be a target of cellular signaling pathways that regulate the functions of Cytc by tissue-specific phosphorylations. So far five phosphorylations sites of Cytc have been mapped and functionally characterized, Tyr97, Tyr48, Thr28, Ser47, and Thr58. All five phosphorylations partially inhibit respiration, which we propose results in optimal intermediate mitochondrial membrane potentials and low ROS production under normal conditions. Four of the phosphorylations result in inhibition of the apoptotic functions of Cytc, suggesting a cytoprotective role for phosphorylated Cytc. Interestingly, these phosphorylati...
Source: The International Journal of Biochemistry and Cell Biology - Category: Biochemistry Authors: Tags: Int J Biochem Cell Biol Source Type: research