Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
17
pubmed:dateCreated
1999-10-28
pubmed:abstractText
Retinol-binding protein (RBP) is the sole specific transport protein for retinol (vitamin A) in the circulation, and its single known function is to deliver retinol to tissues. Within tissues, retinol is activated to retinoic acid, which binds to nuclear receptors to regulate transcription of >300 diverse target genes. In the eye, retinol is also activated to 11-cis-retinal, the visual chromophore. We generated RBP knockout mice (RBP(-/-)) by gene targeting. These mice have several phenotypes. Although viable and fertile, they have reduced blood retinol levels and markedly impaired retinal function during the first months of life. The impairment is not due to developmental retinal defect. Given a vitamin A-sufficient diet, the RBP(-/-) mice acquire normal vision by 5 months of age even though blood retinol levels remain low. Deprived of dietary vitamin A, vision remains abnormal and blood retinol declines to undetectable levels. Another striking phenotype of the mutant mice is their abnormal retinol metabolism. The RBP(-/-) mice can acquire hepatic retinol stores, but these cannot be mobilized. Thus, their vitamin A status is extremely tenuous and dependent on a regular vitamin A intake. Unlike wild-type mice, serum retinol levels in adult RBP(-/-) animals become undetectable after only a week on a vitamin A-deficient diet and their retinal function rapidly deteriorates. Thus RBP is needed for normal vision in young animals and for retinol mobilization in times of insufficient dietary intake, but is otherwise dispensable for the delivery of retinol to tissues.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0261-4189
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4633-44
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:10469643-Age Factors, pubmed-meshheading:10469643-Animals, pubmed-meshheading:10469643-Biological Availability, pubmed-meshheading:10469643-Chromatography, Gel, pubmed-meshheading:10469643-Chromatography, High Pressure Liquid, pubmed-meshheading:10469643-Diet, pubmed-meshheading:10469643-Electroretinography, pubmed-meshheading:10469643-Female, pubmed-meshheading:10469643-Humans, pubmed-meshheading:10469643-Male, pubmed-meshheading:10469643-Mice, pubmed-meshheading:10469643-Mice, Inbred C57BL, pubmed-meshheading:10469643-Mice, Knockout, pubmed-meshheading:10469643-Models, Genetic, pubmed-meshheading:10469643-Retina, pubmed-meshheading:10469643-Retinol-Binding Proteins, pubmed-meshheading:10469643-Spectrometry, Mass, Matrix-Assisted Laser..., pubmed-meshheading:10469643-Time Factors, pubmed-meshheading:10469643-Transgenes, pubmed-meshheading:10469643-Vision, Ocular, pubmed-meshheading:10469643-Vitamin A
pubmed:year
1999
pubmed:articleTitle
Impaired retinal function and vitamin A availability in mice lacking retinol-binding protein.
pubmed:affiliation
Institute of Cancer Research, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.