title: Cyp27c1 Red-Shifts the Spectral Sensitivity of Photoreceptors by Converting Vitamin A1 into A2.
abstract: Some vertebrate species have evolved means of extending their visual sensitivity beyond the range of human vision. One mechanism of enhancing sensitivity to long-wavelength light is to replace the 11-cis retinal chromophore in photopigments with 11-cis 3,4-didehydroretinal. Despite over a century of research on this topic, the enzymatic basis of this perceptual switch remains unknown. Here, we show that a cytochrome P450 family member, Cyp27c1, mediates this switch by converting vitamin A1 (the precursor of 11-cis retinal) into vitamin A2 (the precursor of 11-cis 3,4-didehydroretinal). Knockout of cyp27c1 in zebrafish abrogates production of vitamin A2, eliminating the animal's ability to red-shift its photoreceptor spectral sensitivity and reducing its ability to see and respond to near-infrared light. Thus, the expression of a single enzyme mediates dynamic spectral tuning of the entire visual system by controlling the balance of vitamin A1 and A2 in the eye.
authors.affiliation: Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Enright
authors.affiliation: Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Toomey
authors.affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Shin-ya
authors.initials: SY
authors.lastname: Sato
authors.affiliation: School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK.
authors.forename: Shelby E
authors.initials: SE
authors.lastname: Temple
authors.affiliation: Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Allen
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
authors.forename: Rina
authors.initials: R
authors.lastname: Fujiwara
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
authors.forename: Valerie M
authors.initials: VM
authors.lastname: Kramlinger
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
authors.forename: Leslie D
authors.initials: LD
authors.lastname: Nagy
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Johnson
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: How
authors.affiliation: Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Johnson
authors.affiliation: School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK.
authors.forename: Nicholas W
authors.initials: NW
authors.lastname: Roberts
authors.affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Vladimir J
authors.initials: VJ
authors.lastname: Kefalov
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
authors.forename: F Peter
authors.initials: FP
authors.lastname: Guengerich
authors.affiliation: Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA. Electronic address: jcorbo@pathology.wustl.edu.
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Corbo
mesh_terms: D029845:Amphibian Proteins / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics* / Q000378:metabolism; D007259:Infrared Rays; D020419:Photoreceptor Cells, Vertebrate / Q000502:physiology; D011892:Rana catesbeiana / Q000235:genetics / Q000502:physiology*; D059467:Transcriptome; D014796:Visual Perception; D014801:Vitamin A / Q000031:analogs & derivatives* / Q000378:metabolism*; D015027:Zebrafish / Q000235:genetics / Q000502:physiology*; D029961:Zebrafish Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D029845:Amphibian Proteins; D029961:Zebrafish Proteins; C024366:vitamin A2; D014801:Vitamin A; D003577:Cytochrome P-450 Enzyme System; C000610581:Cyp27c1 protein, zebrafish