Our research is directed toward developing at the molecular level an insight into the biochemistry of the visual process, and in particular how retinoids (vitamine A compounds) are stored, mobilized, transported, isomerized and utilized in the eye. We are also interested in the transport of these and other hydrophobic compounds, such as vitamin E, in the pigment epithelium and interphotoreceptor matrix and we are interested in those properties of the interphotoreceptor matrix that may affect the passage of these substances between the RPE and the retina. We will extend our studies on nutritional deficiencies, and on hereditary and acquired retinal degenerations in animals. We will also continue and expand our work on normal human eyes, so providing a reliable backdrop against which to evaluated our findings on human eyes with retinal degenerations. The distribution and isomerization of retinoids in vivo and in vitro during various stages of the visual cycle will be examined using animals on normal diets and animals on vitamin A-deficient diets supplemented with retinoic acid and pulsed with [3H]-retinoids. The properties of the interphotoreceptor matrix will be examined. This includes a study of the proteoglycans, their state of aggregation and the possible presence of free glycosaminoglycans as a result of proteoglycan degradation. We will also study the glycoproteins of the IPM, and will continue to characterize and study the high Mr glycoprotein that binds retinol and alpha-tocopherol. We will study the pigment epithelium, its role insynthesizing interphotoreceptor matrix and its role in interconverting, isomerizing, transporting and regulating the delivery of retinoids to the retina. We will use the above approaches to study retinal degenerations in animals, both hereditary (Wag-Rij and RCS rats) and acquired (zinc and vitamin A deficiencies). We will also use these approaches to study tissue from human eyes with acquired and hereditary degenerations, including retinitis pigmentosa.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY002489-11
Application #
3256813
Study Section
Visual Sciences A Study Section (VISA)
Project Start
1979-02-01
Project End
1987-10-15
Budget Start
1987-02-01
Budget End
1987-10-15
Support Year
11
Fiscal Year
1987
Total Cost
Indirect Cost
Name
Baylor College of Medicine
Department
Type
Schools of Medicine
DUNS #
074615394
City
Houston
State
TX
Country
United States
Zip Code
77030
Fong, S L; Fong, W B; Morris, T A et al. (1990) Characterization and comparative structural features of the gene for human interstitial retinol-binding protein. J Biol Chem 265:3648-53
Gonzalez-Fernandez, F; Healy, J I (1990) Early expression of the gene for interphotoreceptor retinol-binding protein during photoreceptor differentiation suggests a critical role for the interphotoreceptor matrix in retinal development. J Cell Biol 111:2775-84
Liou, G I; Ma, D P; Yang, Y W et al. (1989) Human interstitial retinoid-binding protein. Gene structure and primary structure. J Biol Chem 264:8200-6
Bridges, C D (1989) Distribution of retinol isomerase in vertebrate eyes and its emergence during retinal development. Vision Res 29:1711-7
Lin, Z S; Fong, S L; Bridges, C D (1989) Retinoids bound to interstitial retinol-binding protein during light and dark-adaptation. Vision Res 29:1699-709
Fong, S L; Balakier, H; Canton, M et al. (1988) Retinoid-binding proteins in retinoblastoma tumors. Cancer Res 48:1124-8
Fong, S L; Bridges, C D (1988) Internal quadruplication in the structure of human interstitial retinol-binding protein deduced from its cloned cDNA. J Biol Chem 263:15330-4
Fong, S L; Lee, P G; Ozaki, K et al. (1988) IRBP-like proteins in the eyes of six cephalopod species--immunochemical relationship to vertebrate interstitial retinol-binding protein (IRBP) and cephalopod retinal-binding protein. Vision Res 28:563-73
Bridges, C D; Alvarez, R A; Fong, S L et al. (1987) Rhodopsin, vitamin A, and interstitial retinol-binding protein in the rd chicken. Invest Ophthalmol Vis Sci 28:613-7
Alvarez, R A; Liou, G I; Fong, S L et al. (1987) Levels of alpha- and gamma-tocopherol in human eyes: evaluation of the possible role of IRBP in intraocular alpha-tocopherol transport. Am J Clin Nutr 46:481-7

Showing the most recent 10 out of 21 publications