title: Chromophore supply rate-limits mammalian photoreceptor dark adaptation.
abstract: Efficient regeneration of visual pigment following its destruction by light is critical for the function of mammalian photoreceptors. Here, we show that misexpression of a subset of cone genes in the rd7 mouse hybrid rods enables them to access the normally cone-specific retina visual cycle. The rapid supply of chromophore by the retina visual cycle dramatically accelerated the mouse rod dark adaptation. At the same time, the competition between rods and cones for retina-derived chromophore slowed cone dark adaptation, indicating that the cone specificity of the retina visual cycle is key for rapid cone dark adaptation. Our findings demonstrate that mammalian photoreceptor dark adaptation is dominated by the supply of chromophore. Misexpression of cone genes in rods may represent a novel approach to treating visual disorders associated with mutations of visual cycle proteins or with reduced retinal pigment epithelium function due to aging.
authors.affiliation: Departments of Ophthalmology and Visual Sciences and.
authors.forename: Jin-shan
authors.initials: JS
authors.lastname: Wang
authors.affiliation: Departments of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, Department of Electronics and Communications Engineering, Tampere University of Technology and BioMediTech, FI-33014 Tampere, Finland, and.
authors.forename: Soile
authors.initials: S
authors.lastname: Nymark
authors.affiliation: Departments of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118.
authors.forename: Rikard
authors.initials: R
authors.lastname: Frederiksen
authors.affiliation: Departments of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, Department of Neuroscience, Brown University, Providence, Rhode Island 02912.
authors.forename: Maureen E
authors.initials: ME
authors.lastname: Estevez
authors.affiliation: Departments of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110.
authors.forename: Susan Q
authors.initials: SQ
authors.lastname: Shen
authors.affiliation: Departments of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110.
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Corbo
authors.affiliation: Departments of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118.
authors.forename: M Carter
authors.initials: MC
authors.lastname: Cornwall
authors.affiliation: Departments of Ophthalmology and Visual Sciences and kefalov@wustl.edu.
authors.forename: Vladimir J
authors.initials: VJ
authors.lastname: Kefalov
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D003623:Dark Adaptation / Q000502:physiology*; D005260:Female; D044385:GTP-Binding Protein alpha Subunits / Q000235:genetics; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009457:Neuroglia / Q000502:physiology; D057093:Orphan Nuclear Receptors / Q000235:genetics; D010775:Photic Stimulation; D012160:Retina / Q000166:cytology / Q000528:radiation effects; D017949:Retinal Cone Photoreceptor Cells / Q000502:physiology*; D012162:Retinal Degeneration / Q000235:genetics / Q000473:pathology; D017948:Retinal Rod Photoreceptor Cells / Q000502:physiology* / Q000528:radiation effects; D012243:Rhodopsin / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D015293:Transducin / Q000235:genetics; D014801:Vitamin A / Q000494:pharmacology; D014815:Vitamins / Q000494:pharmacology
chemical_list: D044385:GTP-Binding Protein alpha Subunits; C488949:Gnat1 protein, mouse; C485736:Nr2e3 protein, mouse; D057093:Orphan Nuclear Receptors; D014815:Vitamins; D014801:Vitamin A; D012243:Rhodopsin; D015293:Transducin
keywords: dark adaptation; photoreceptors; pigment regeneration; retina; retinol dehydrogenase; visual cycle