Retinoids pp 115-127 | Cite as

Measurement of the Mobility of All-Trans-Retinol with Two-Photon Fluorescence Recovery After Photobleaching

  • Yiannis Koutalos
Part of the Methods in Molecular Biology book series (MIMB, volume 652)


The mobility of all-trans-retinol makes a crucial contribution to the rate of the reactions in which it participates. This is even more so because of its low aqueous solubility, which makes the presence of carrier proteins and the spatial arrangement of cellular membranes especially relevant. In rod photoreceptor outer segments, all-trans-retinol is generated after light exposure from the reduction of all-trans-retinal that is released from bleached rhodopsin. The mobility of all-trans-retinol in rod outer segments was measured with fluorescence recovery after photobleaching (FRAP), using two-photon excitation of its fluorescence. The values of the lateral and axial diffusion coefficients indicate that most of the all-trans-retinol in rod outer segments move unrestricted and without being aided by carriers.

Key words

Photoreceptors rod outer segment retina visual cycle rhodopsin diffusion 


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Yiannis Koutalos
    • 1
  1. 1.Departments of Ophthalmology and NeurosciencesMedical University of South CarolinaCharlestonUSA

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