Thermal fluctuations of individual semiflexible polymers in confined geometry
نویسندگان
چکیده
Thermal fluctuations of individual actin filaments confined in rectangular microchannels with dimensions similar to the mesh size of the cytoskeleton in eukaryotic cells were studied using fluorescence microscopy. We observed a strong dependence of the tangent correlation on both channel width and filament length. Compared to freely fluctuating filaments, long filaments confined in narrow channels exhibit an enhanced tangent correlation with a local minimum. These unique characteristics may be described by an analytical expression assuming the confining energy as a parabolic potential. We find the d law for the deflection length λ, which has been theoretically predicted for circular tubes and a hard wall potential, experimentally confirmed.
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