EPL, 84 (2008) 18003
DOI: 10.1209/0295-5075/84/18003

Buckling and force propagation along intracellular microtubules

Moumita Das^{1, 2}, Alex J. Levine³ and F. C. MacKintosh<sup>1, 2

1</sup>   Department of Physics and Astronomy, Vrije Universiteit - Amsterdam, The Netherlands, EU
²   The Aspen Center for Physics - Aspen, CO 81611, USA
³   Department of Chemistry and Biochemistry, and University of California - Los Angeles, CA 90095, USA California Nanosystems Institute, University of California - Los Angeles, CA 90095, USA

mdas@few.vu.nl

received 18 April 2008; accepted in final form 27 August 2008; published October 2008
published online 23 September 2008

Abstract
Motivated by recent experiments showing the compressive buckling of microtubules in cells, we study theoretically the mechanical response of and force propagation along elastic filaments embedded in a non-linear elastic medium. We find that embedded microtubules buckle when their compressive load exceeds a critical value f_c, and that the resulting deformation is restricted to a penetration depth that depends on both the non-linear material properties of the surrounding cytoskeleton, as well as the direct coupling of the microtubule to the cytoskeleton. The deformation amplitude depends on the applied load f > f_c as (f-f_c)^1/2. This work shows how the range of compressive force transmission by microtubules can be tens of microns and is governed by the mechanical coupling to the surrounding cytoskeleton.

PACS
87.16.Ka - Filaments, microtubules, their networks, and supramolecular assemblies.
62.20.de - Elastic Moduli.
82.35.Pq - Biopolymers, biopolymerization.

© EPLA 2008