Human ocular carotenoid-binding proteins

Photochem Photobiol Sci. 2010 Nov;9(11):1418-25. doi: 10.1039/c0pp00126k. Epub 2010 Sep 3.

Abstract

Two dietary carotenoids, lutein and zeaxanthin, are specifically delivered to the human macula at the highest concentration anywhere in the body. Whenever a tissue exhibits highly selective uptake of a compound, it is likely that one or more specific binding proteins are involved in the process. Over the past decade, our laboratory has identified and characterized several carotenoid-binding proteins from human retina including a pi isoform of glutathione S-transferase (GSTP1) as a zeaxanthin-binding protein, a member of the steroidogenic acute regulatory domain (StARD) family as a lutein-binding protein, and tubulin as a less specific, but higher capacity site for carotenoid deposition. In this article, we review the purification and characterization of these carotenoid-binding proteins, and we relate these ocular carotenoid-binding proteins to the transport and uptake role of serum lipoproteins and scavenger receptor proteins in a proposed pathway for macular pigment carotenoid delivery to the human retina.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Biological Transport
  • Carotenoids / metabolism*
  • Glutathione S-Transferase pi / isolation & purification*
  • Glutathione S-Transferase pi / metabolism
  • Humans
  • Lipoproteins / metabolism
  • Membrane Transport Proteins / isolation & purification*
  • Membrane Transport Proteins / metabolism
  • Protein Binding
  • Retina / metabolism*

Substances

  • Lipoproteins
  • Membrane Transport Proteins
  • Carotenoids
  • Glutathione S-Transferase pi