The effect of microtubule deformation on the efficiency of motor protein walkers

Microtubules are an important component of the cytoskeleton of cells. They provide not only structural support, but also connectivity between different regions of the cell. Motor proteins transport tethered cargo by walking along microtubules, which may be deformed in the complex environment of the cell. Since the length of the microtubule is measured in micrometers, while motor proteins operate on the nanometer scale, computer simulations of walking motor proteins have to bridge multiple length scales. In recent work, Zhang and Wang [1] developed a micromechanical microtubule model that can be efficiently simulated with finite element methods and mapped back to an interaction site model on the nanometer scale. In this work, we simulate motor proteins walking on deformed microtubules by combining finite element calculations of microtubules under stress with Brownian dynamics simulations of a coarse-grained model for motor proteins. We report on our method for bridging the length scales and present results for the effect of microtubule deformation on the efficiency of motor protein walkers.
[1] J. Zhang and C. Wang. Biomech. Model Mechanobiol. 13, 1175 (2014).