Retinoids in the visual cycle: role of the retinal G protein-coupled receptor

Autor: Elliot H. Choi, Krzysztof Palczewski, Anahita Daruwalla, Susie Suh, Henri Leinonen
Rok vydání: 2021
Předmět:
0301 basic medicine
Opsin
retina
genetic structures
RALBP
retinal-binding protein

retinal pigment epithelium
030204 cardiovascular system & hematology
Medical Biochemistry and Metabolomics
Eye
Biochemistry
vitamin A
Rgr−/−
Rgr knockout

RDH10
retinol dehydrogenase 10

0302 clinical medicine
Endocrinology
retinal pigment epithelium-retinal G proteincoupled receptor opsin
RDH5
11-cis-retinol dehydrogenase 5

RE
retinyl ester

Chemistry
Gnat1−/−
Gnat1 knockout

GPCR
G protein-coupled receptor

IRBP
interphotoreceptor retinoid-binding protein

Cell biology
medicine.anatomical_structure
Retinaldehyde
Visual phototransduction
vision
Biochemistry & Molecular Biology
RPE
retinal pigment epithelium

RPE65
retinal pigment epithelium-specific 65 kDa

CRALBP
cellular retinaldehyde-binding protein

QD415-436
Thematic Review Series: Seeing 2020:Lipids and Lipid-Soluble Molecules in the Eye
photoisomerase
03 medical and health sciences
visual pigments
medicine
Retinal G protein coupled receptor
CDHR1
cadherin-related family member 1

Eye Disease and Disorders of Vision
ERG
electroretinography

Retina
Retinal pigment epithelium
LRAT
lecithin:retinol acyltransferase

retinal pigment epithelium-retinal G protein-coupled receptor opsin
Neurosciences
visual chromophore
Thematic Review Series
Photoisomerase
Cell Biology
eye diseases
030104 developmental biology
RGR
retinal pigment epithelium-retinal G protein-coupled receptor

RPE65
sense organs
Biochemistry and Cell Biology
Zdroj: Journal of Lipid Research
Journal of Lipid Research, Vol 62, Iss, Pp 100040-(2021)
Popis: Driven by the energy of a photon, the visual pigments in rod and cone photoreceptor cells isomerize 11-cis-retinal to the all-trans configuration. This photochemical reaction initiates the signal transduction pathway that eventually leads to the transmission of a visual signal to the brain and leaves the opsins insensitive to further light stimulation. For the eye to restore light sensitivity, opsins require recharging with 11-cis-retinal. This trans-cis back conversion is achieved through a series of enzymatic reactions composing the retinoid (visual) cycle. Although it is evident that the classical retinoid cycle is critical for vision, the existence of an adjunct pathway for 11-cis-retinal regeneration has been debated for many years. Retinal pigment epithelium (RPE)-retinal G protein-coupled receptor (RGR) has been identified previously as a mammalian retinaldehyde photoisomerase homologous to retinochrome found in invertebrates. Using pharmacological, genetic, and biochemical approaches, researchers have now established the physiological relevance of the RGR in 11-cis-retinal regeneration. The photoisomerase activity of RGR in the RPE and Müller glia explains how the eye can remain responsive in daylight. In this review, we will focus on retinoid metabolism in the eye and visual chromophore regeneration mediated by RGR.
Databáze: OpenAIRE