Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2002-1-28
pubmed:abstractText
Light-dependent production of 11-cis-retinal by the retinal pigment epithelium (RPE) and normal regeneration of rhodopsin under photic conditions involve the RPE retinal G protein-coupled receptor (RGR) opsin. This microsomal opsin is bound to all-trans-retinal which, upon illumination, isomerizes stereospecifically to the 11-cis isomer. In this paper, we investigate the synthesis of the all-trans-retinal chromophore of RGR in cultured ARPE-hRGR and freshly isolated bovine RPE cells. Exogenous all-trans-[(3)H]retinol is incorporated into intact RPE cells and converted mainly into retinyl esters and all-trans-retinal. The intracellular processing of all-trans-[(3)H]retinol results in physiological binding to RGR of a radiolabeled retinoid, identified as all-trans-[(3)H]retinal. The ARPE-hRGR cells contain a membrane-bound NADPH-dependent retinol dehydrogenase that reacts efficiently with all-trans-retinol but not the 11-cis isomer. The NADPH-dependent all-trans-retinol dehydrogenase activity in isolated RPE microsomal membranes can be linked in vitro to specific binding of the chromophore to RGR. These findings provide confirmation that RGR opsin binds the chromophore, all-trans-retinal, in the dark. A novel all-trans-retinol dehydrogenase exists in the RPE and performs a critical function in chromophore biosynthesis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3318-24
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Synthesis of the all-trans-retinal chromophore of retinal G protein-coupled receptor opsin in cultured pigment epithelial cells.
pubmed:affiliation
Department of Microbiology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.