One-Dimensional Diffusion of Tau Protein Guided by the Microtubule Lattice

Abstract

protofilaments. Previous experiments to characterize the stiffness of microtubules have generally relied on heterogeneous ensembles of microtubules with different structures, complicating the interpretation and comparison of stiffness measurements. We report on a kinesin-driven microtubule gliding experiment that simultaneously determines the stiffness and protofilament number (diameter) of individual microtubules, allowing us to distinguish stiffness for microtubules of 12-14 protofilaments (including two different 14 protofilament lattice structures). The scaling of our stiffness measurements are consistent with previous theories connecting protofilament number to stiffness, but also suggest an alternate correlation between stiffness and protofilament superhelical pitch.