April 2011
Volume 52, Issue 14
Free
ARVO Annual Meeting Abstract  |   April 2011
Expression of β-Carotene 9’, 10’ Monooxygenase (BCO2) In Human Retina And RPE-Choroid
Author Affiliations & Notes
  • Binxing Li
    Ophthalmology and Visual Sciences, Univ of UT Sch Med/Moran Eye Ctr, Salt Lake City, Utah
  • Jeanne M. Frederick
    Ophthalmology and Visual Sciences, Univ of UT Sch Med/Moran Eye Ctr, Salt Lake City, Utah
  • Paul S. Bernstein
    Ophthalmology and Visual Sciences, Univ of UT Sch Med/Moran Eye Ctr, Salt Lake City, Utah
  • Footnotes
    Commercial Relationships  Binxing Li, None; Jeanne M. Frederick, None; Paul S. Bernstein, None
  • Footnotes
    Support  NEI Grant EY11600; Lowy Medical Research Institute; Research to Prevent Blindness
Investigative Ophthalmology & Visual Science April 2011, Vol.52, 2329. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Binxing Li, Jeanne M. Frederick, Paul S. Bernstein; Expression of β-Carotene 9’, 10’ Monooxygenase (BCO2) In Human Retina And RPE-Choroid. Invest. Ophthalmol. Vis. Sci. 2011;52(14):2329.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: : β-Carotene 9’, 10’ monooxygenase (BCO2) specifically cleaves the 9’, 10’-double bond of β-carotene, lycopene, and possibly xanthophylls. Genetic variations in the BCO2 gene have been found to be associated with lutein accumulation in animals. Human BCO2 exists in two isoforms: one variant (V1) of 579 amino acids and the other variant (V2) of 545 amino acids. To determine whether BCO2 is present and participates in carotenoid metabolism of the primate retina, we investigated the expression of BCO2 (V1) and (V2) in human retina, RPE-choroid, and liver.

Methods: : RT-PCR was used to test mRNA transcription of BCO2 in human retina, RPE-choroid and liver. Western blots and immunohistochemistry using a commercially-available antibody that can recognize both BCO2 (V1) and (V2) were used to probe the expression and distribution of BCO2 in human and monkey retina.

Results: : RT-PCR detected stronger mRNA expression of BCO2 (V1) in human retina with a 440-bp band and higher mRNA expression of BCO2 (V2) in human RPE-choroid and liver with a 170-bp band. Immunoblot results showed a 63-kDa band in human retina and a 59-kDa band in human RPE-choroid and liver, suggesting that BCO2 (V1) is expressed specifically in retina, whereas BCO2 (V2) is expressed predominantly in RPE-choroid and liver. Immunohistochemistry results revealed that BCO2 (V1) is localized broadly among neuronal cell bodies of monkey retina.

Conclusions: : Human BCO2 (V1) is expressed specifically in human retina, while BCO2 (V2) is expressed in human RPE-choroid and liver. This specific and distinct tissue distribution of human BCO2 (V1) and (V2) indicates that they may play different roles in human ocular carotenoid metabolism. Functional studies of their enzymatic activities and specificities are in progress.

Keywords: retina • macular pigment • carotenoids/carotenoid binding proteins 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×