title: Membrane receptors and transporters involved in the function and transport of vitamin A and its derivatives.
abstract: The eye is the human organ most sensitive to vitamin A deficiency because of vision's absolute and heavy dependence on vitamin A for light perception. Studies of the molecular basis of vision have provided important insights into the intricate mechanistic details of the function, transport and recycling of vitamin A and its derivatives (retinoid). This review focuses on retinoid-related membrane receptors and transporters. Three kinds of mammalian membrane receptors and transporters are discussed: opsins, best known as vitamin A-based light sensors in vision; ABCA4, an ATP-dependent transporter specializes in the transport of vitamin A derivative; and STRA6, a recently identified membrane receptor that mediates cellular uptake of vitamin A. The evolutionary driving forces for their existence and the wide spectrum of human diseases associated with these proteins are discussed. Lessons learned from the study of the visual system might be useful for understanding retinoid biology and retinoid-related diseases in other organ systems as well. This article is part of a Special Issue entitled Retinoid and Lipid Metabolism.
authors.affiliation: Department of Physiology, Jules Stein Eye Institute, Brian Research Institute, and Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, CA, USA. hsun@mednet.ucla.edu
authors.forename: Hui
authors.initials: H
authors.lastname: Sun
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000378:metabolism*; D000818:Animals; D005075:Biological Evolution; D001692:Biological Transport; D005123:Eye / Q000378:metabolism; D005128:Eye Diseases / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism; D051379:Mice; D055355:Opsins / Q000378:metabolism*; D014801:Vitamin A / Q000378:metabolism*; D014802:Vitamin A Deficiency
chemical_list: C056475:ABCA4 protein, human; D018528:ATP-Binding Cassette Transporters; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D055355:Opsins; C519685:STRA6 protein, human; D014801:Vitamin A