Journal
ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS
Volume 539, Issue 2, Pages 181-186Publisher
ELSEVIER SCIENCE INC
DOI: 10.1016/j.abb.2013.07.008
Keywords
Carotenoids; Interphotoreceptor matrix; Interphotoreceptor retinoid-binding protein; Macular pigments; Retinoids; Surface plasmon resonance
Categories
Funding
- NIH [R01 EY11600]
- Lowy Medical Research Foundation
- core instrumentation grant [EY14800]
- Merit Review Award [I01BX007080]
- Biomedical Laboratory Research and Development Service of the Veterans Affairs Office of Research and Development [NIH R01 EY09412, R24 EY 016662]
- Department of Ophthalmology at State University of New York at Buffalo
- Moran Eye Center, University of Utah
Ask authors/readers for more resources
Uptake, transport and stabilization of xanthophylls in the human retina are important components of a complex multistep process that culminates in a non-uniform distribution of these important nutrients in the retina. The process is far from understood; here, we consider the potential role of interphotoreceptor retinoid-binding protein (IRBP) in this process. IRBP is thought to facilitate the exchange of 11-cis-retinal, 11-cis-retinol and all-trans-retinol between the retinal pigment epithelium (RPE), photoreceptors and Muller cells in the visual cycle. Structural and biochemical studies suggest that IRBP has a variety of non-equivalent ligand binding sites that function in this process. IRBP is multifunctional, being able to bind a variety of physiologically significant molecules including fatty acids in the subretinal space. This wide range of binding activities is of particular interest because it is unknown whether the lutein and zeaxanthin found in the macula originate from the choroidal or retinal circulations. If from the choroidal circulation, then IRBP is a likely mediator for their transport across the interphotoreceptor matrix. In this report, we explore the binding interactions of retinoids, fatty acids, and carotenoids with IRBP using surface plasmon resonance (SPR)-based biosensors. IRBP showed similar affinity toward retinoids and carotenoids (1-2 piM), while fatty acids had approximately 10 times less affinity. These results suggest that further studies should be carried out to evaluate whether IRBP has a physiologically relevant role in binding lutein and zeaxanthin in the interphotoreceptor matrix. (C) 2013 Elsevier Inc. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available