Mechanical Heterogeneity of Microtubules

Abstract

The study of microtubule deflection under force lies exactly on the interface of biology and physics. Microtubules are polyproteins that assemble into rigid beams, that carry biologically relevant forces. To quantify this rigidity, much research has been done in the past 40 years. First measurements matched to Euler-Bernoulli beam theory to get the material properties of microtubules and found varying results. In the subsequent years in vitro work with various techniques of applying force on microtubules have given better estimates of rigidity, found that rigidity can depend on length and polymerization speed, and have shown that in many conditions more complicated beam models may be necessary. However, variation in sample preparation that yield different lattices or dynamics stabilization are still often present. This review serves to assess the state of the field, provide an overview, and propose a direction to attempt further microtubule rigidity studies in tandem with novel microscopy methods to try to link biophysical properties to the microtubule structure.