An extracellular retinol-binding glycoprotein in the rat eye-characterization, localization and biosynthesis

F. Gonzalez-Fernandez, R. A. Landers, P. A. Glazebrook, S. L. Fong, G. I. Liou, D. M.K. Lam, C. D.B. Bridges

Research output: Contribution to journalArticlepeer-review

1 Scopus citations


We have identified and partially purified interstitial retinol-binding protein (IRBP) from the subretinal space of the rat. It appeared to be glycosylated. Its apparent mol. wt was 270,000 by gel-filtration and 144,000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Rat IRBP cross-reacted with anti-bovine IRBP sheep and rabbit sera, bound all-trans-[15-3H] retinol and was bound by concanavalin A. IRBP was not detected in the cytosols of the neural retina or retinal pigment epithelium and choroid. This distribution was confirmed by immunocytochemistry using a fluorescence-labeled second antibody. Immunospecific fluorescence was most intense in the interphotoreceptor matrix in a 6.5 μm band adjacent to the retinal pigment epithelium. It was less intense over the remainder of the rod outer segment layer and was comparatively faint over the inner segment region. Its occurrence in the interstitial space between the photoreceptors and retinal pigment epithelium coupled with the fact it bound all-trans-[15-3H] retinol supports the concept that it may be implicated in the transport of retinoids between the retina and the retinal pigment epithelium during the visual cycle. When incubated with [3H]leucine or [3H]glucosamine, isolated retinas (but not retinal pigment epithelium and choroid) secreted labeled IRBP into the medium. This suggests that the retina plays a role in regulating the amount of IRBP in the subretinal space.

Original languageEnglish (US)
Pages (from-to)533-540
Number of pages8
JournalNeurochemistry International
Issue number3
StatePublished - 1985

ASJC Scopus subject areas

  • Cellular and Molecular Neuroscience
  • Cell Biology


Dive into the research topics of 'An extracellular retinol-binding glycoprotein in the rat eye-characterization, localization and biosynthesis'. Together they form a unique fingerprint.

Cite this