title: Metabolic and redox signaling in the retina.
abstract: Visual perception by photoreceptors relies on the interaction of incident photons from light with a derivative of vitamin A that is covalently linked to an opsin molecule located in a special subcellular structure, the photoreceptor outer segment. The photochemical reaction produced by the photon is optimal when the opsin molecule, a seven-transmembrane protein, is embedded in a lipid bilayer of optimal fluidity. This is achieved in vertebrate photoreceptors by a high proportion of lipids made with polyunsaturated fatty acids, which have the detrimental property of being oxidized and damaged by light. Photoreceptors cannot divide, but regenerate their outer segments. This is an enormous energetic challenge that explains why photoreceptors metabolize glucose through aerobic glycolysis, as cancer cells do. Uptaken glucose produces metabolites to renew that outer segment as well as reducing power through the pentose phosphate pathway to protect photoreceptors against oxidative damage.
authors.affiliation: Department of Genetics, Institut de la Vision, Sorbonne Universités, UPMC Univ Paris 06 UMR_S968, INSERM_U968, CNRS UMR_7210, 17 rue Moreau, 75012, Paris, France. thierry.leveillard@inserm.fr.
authors.forename: Thierry
authors.identifier: 0000-0001-5692-8770
authors.initials: T
authors.lastname: Léveillard
authors.affiliation: Department of Genetics, Institut de la Vision, Sorbonne Universités, UPMC Univ Paris 06 UMR_S968, INSERM_U968, CNRS UMR_7210, 17 rue Moreau, 75012, Paris, France.|CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC_1423, 28 rue de Charenton, 75012, Paris, France.
authors.forename: José-Alain
authors.initials: JA
authors.lastname: Sahel
mesh_terms: D000818:Animals; D005227:Fatty Acids / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010427:Pentose Phosphate Pathway; D010786:Photoreceptor Cells / Q000166:cytology / Q000378:metabolism*; D012160:Retina / Q000378:metabolism*; D012164:Retinal Diseases / Q000378:metabolism*; D012243:Rhodopsin / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D005227:Fatty Acids; D012243:Rhodopsin; D005947:Glucose
keywords: Aerobic glycolysis; Cone photoreceptor; Glucose transporter; Nucleoredoxin-like genes; Pentose phosphate pathway; Retinal degeneration; Rod-derived cone viability factor; Thioredoxin