Synthesis and secretion of interstitial retinol-binding protein by the human retina

Journal Article · Tue Jan 01 04:00:00 EST 1985 · Invest. Ophthalmol. Visual Sci.; (United States)

OSTI ID:5710003

Hollyfield, J G; Fliesler, S J; Rayborn, M E; Fong, S L; Landers, R A; Bridges, C D

Interstitial retinol-binding protein (IRBP) is a soluble glycoprotein present between the retina and pigmented epithelium, which may function to shuttle vitamin A derivatives between these tissues. While previous studies have shown that the retina is solely responsible for IRBP synthesis, the specific retinal cell(s) in which this occurs has not been established. Since the carbohydrate moiety of IRBP contains fucose, the authors have analyzed the sites of incorporation of /sup 3/H-fucose in the human retina in vitro, using autoradiography. Following a 30-min pulse incubation, all retinal layers exhibited incorporation of label; however, the rod photoreceptor inner segments contained one- to two-fold more radioactivity than was present in any other retinal compartment. In autoradiographs of retinas recovered following a 4 hr chase incubation, all retinal layers retained similar levels of radioactivity with the exception of the rod photoreceptors, cone photoreceptors and cells in the inner nuclear layer, which lost 75, 11, and 14 percent, respectively of the radioactivity present immediately following the 30-min pulse. Proteins present in the chase incubation medium were analyzed by polyacrylamide gel electrophoresis and fluorography. The principal labeled component in the chase medium was identified as IRBP by immunoprecipitation with antibovine-IRBP immunoglobulins.

• Research Organization: Baylor Coll. of Medicine, Houston, TX
• OSTI ID: 5710003
• Journal Information: Invest. Ophthalmol. Visual Sci.; (United States), Journal Name: Invest. Ophthalmol. Visual Sci.; (United States) Vol. 26:1; ISSN IOVSD
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AUTORADIOGRAPHY
BIOSYNTHESIS
BODY
BODY AREAS
CARBOHYDRATES
CHEMICAL BONDS
ELECTROPHORESIS
EYES
FACE
GLOBULINS
GLUCOPROTEINS
HEAD
IMMUNOGLOBULINS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
ORGANIC COMPOUNDS
ORGANS
PROTEINS
RETINA
SACCHARIDES
SENSE ORGANS
SYNTHESIS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VITAMIN A
VITAMINS