Biophysical Journal 70: 1830-1835 (1996)
© 1996 the Biophysical Society

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Irving, M Search for Related Content PubMed PubMed Citation Articles by Irving, M

Steady-state polarization from cylindrically symmetric fluorophores undergoing rapid restricted motion.

Randall Institute, King's College London, England. udbp075@uk.ac.kcl.cc.bay

ABSTRACT

Steady-state fluorescence polarization measurements provide a relatively simple method for investigating the orientation of molecular components in ordered biological systems. However, the observed fluorescence polarization ratios also depend on any mobility of the fluorophores on the time scale of the fluorescence lifetime. Such mobility commonly arises from incomplete immobilization of a fluorescent probe on the macromolecule of interest. A theoretical formalism is presented for the interpretation of steady-state fluorescence polarization ratios in the presence of such rapid fluorophore motion. It is assumed that the fluorophores move freely within a cone between absorption and emission of a photon. Only one new parameter is introduced to describe fluorophore motion, the semi-angle of the cone, and this can be measured in separate experiments on an isotropic system. The fluorophore orientations are assumed to have cylindrical symmetry, but the symmetry axis need not be in the same plane as the center axes of the absorption and emission cones. This geometry applies to muscle and other biological fibers.

This article has been cited by other articles:

				M. G. Bell, E. B. Lankford, G. E. Gonye, G. C. R. Ellis-Davies, D. A. Martyn, M. Regnier, and R. J. Barsotti Kinetics of Cardiac Thin-Filament Activation Probed by Fluorescence Polarization of Rhodamine-Labeled Troponin C in Skinned Guinea Pig Trabeculae Biophys. J., January 15, 2006; 90(2): 531 - 543. [Abstract] [Full Text] [PDF]

				Yu. S. Borovikov, I. V. Dedova, C. G. dos Remedios, N. N. Vikhoreva, P. G. Vikhorev, S. V. Avrova, T. L. Hazlett, and B. W. Van Der Meer Fluorescence Depolarization of Actin Filaments in Reconstructed Myofibers: The Effect of S1 or pPDM-S1 on Movements of Distinct Areas of Actin Biophys. J., May 1, 2004; 86(5): 3020 - 3029. [Abstract] [Full Text] [PDF]

				D. M. Warshaw, E. Hayes, D. Gaffney, A.-M. Lauzon, J. Wu, G. Kennedy, K. Trybus, S. Lowey, and C. Berger Myosin conformational states determined by single fluorophore polarization PNAS, July 7, 1998; 95(14): 8034 - 8039. [Abstract] [Full Text] [PDF]