Share Email Print

Journal of Biomedical Optics • Open Access

Application of fluorescence polarization microscopy to measure fluorophore orientation in the outer hair cell plasma membrane
Author(s): Jennifer N. Greeson; Robert M. Raphael

Paper Abstract

The biophysical properties and organization of cell membranes regulate many membrane-based processes, including electromotility in outer hair cells (OHCs) of the cochlea. Studies of the membrane environment can be carried out by measuring the orientation of membrane-bound fluorophores using fluorescence polarization microscopy (FPM). Due to the cylindrical shape of OHCs, existing FPM theory developed for spherical cells is not applicable. We develop a new method for analyzing FPM data suitable for the quasi-cylindrical OHC. We present the theory for this model, as well as a study of the orientation of the fluorescent probe pyridinium, 4-[2-[6-(dioctylamino)-2-naphthalenyl]ethenyl]-1-(3-sulfopropyl) (di-8-ANEPPS) in the OHC membrane. Our results indicate that the absorption transition dipole moment of di-8-ANEPPS orients symmetrically about the membrane normal at 27 deg with respect to the plane of the membrane. The observed agreement between theoretical predictions and experimental measurements establishes the applicability of FPM to study OHC plasma membrane properties.

Paper Details

Date Published: 1 March 2007
PDF: 9 pages
J. Biomed. Opt. 12(2) 021002 doi: 10.1117/1.2717499
Published in: Journal of Biomedical Optics Volume 12, Issue 2
Show Author Affiliations
Jennifer N. Greeson, Rice Univ. (United States)
Robert M. Raphael, Rice Univ. (United States)

© SPIE. Terms of Use
Back to Top