Effect of molecular walkers on microtubule substrates

Motor proteins are molecular motors that convert chemical energy into directed motion. Kinesin molecules, for example, step in a hand-over-hand fashion on microtubules to transport cargo within a cell. In recent work, we developed a model for a molecular walker that can be simulated efficiently with Brownian dynamics simulations in 3-d. By studying the biological system of kinesins on microtubules, we were able to mimic key aspects of its structure and interactions that allow us to simulate a highly efficient molecular walker on a rigid microtubule. Recent experimental studies suggests that kinesin binding causes conformational changes in microtubules that increase the binding affinity of kinesins to the substrate. To investigate this, we include the motion of microtubule units in our simulations and study the effect of the motor protein on the microtubule substrate. In this work, we present simulation results for a coarse-grained microtubule model that responds to the stepping of molecular walkers and investigate the character and range of the conformational changes.