title: Hiding in plain sight: uncovering a new function of vitamin A in redox signaling.
abstract: The protein kinase Cδ signalosome modulates the generation of acetyl-Coenzyme A from glycolytic sources. This module is composed of four interlinked components: PKCδ, the signal adapter p66Shc, cytochrome c, and vitamin A. It resides in the intermembrane space of mitochondria, and is at the center of a feedback loop that senses upstream the redox balance between oxidized and reduced cytochrome c as a measure of the workload of the respiratory chain, and transmits a forward signal to the pyruvate dehydrogenase complex to adjust the flux of fuel entering the tricarboxylic acid cycle. The novel role of vitamin A as co-activator and potential electron carrier, required for redox activation of PKCδ, is discussed. This article is part of a Special Issue entitled Retinoid and Lipid Metabolism.
authors.affiliation: Immunology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Avenue, New York, NY 10065, USA.
authors.forename: Beatrice
authors.initials: B
authors.lastname: Hoyos
authors.forename: Rebeca
authors.initials: R
authors.lastname: Acin-Perez
authors.forename: Donald A
authors.initials: DA
authors.lastname: Fischman
authors.forename: Giovanni
authors.initials: G
authors.lastname: Manfredi
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hammerling
mesh_terms: D000105:Acetyl Coenzyme A / Q000378:metabolism; D000818:Animals; D002952:Citric Acid Cycle / Q000502:physiology; D045304:Cytochromes c / Q000378:metabolism; D004579:Electron Transport / Q000502:physiology; D006801:Humans; D008928:Mitochondria / Q000378:metabolism; D010084:Oxidation-Reduction; D010085:Oxidative Phosphorylation; D051745:Protein Kinase C-delta / Q000378:metabolism*; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism; D015398:Signal Transduction; D014801:Vitamin A / Q000031:analogs & derivatives / Q000378:metabolism*
chemical_list: D011768:Pyruvate Dehydrogenase Complex; D014801:Vitamin A; C031469:anhydrovitamin A; D000105:Acetyl Coenzyme A; D045304:Cytochromes c; D051745:Protein Kinase C-delta