Mechanics of Microtubules Buckling Supported by Cytoplasm

The cytoskeleton provides the mechanical scaffold and maintains the integrity of cells.  It is usually believed that one type of cytoskeleton biopolymer, microtubules, bear compressive force.  In vitro experiments found that isolated microtubules may form an Euler buckling pattern with a long wavelength for very small compressive force.  This, however, does not agree with in vivo experiments where microtubules buckle with short-wavelength.  In order to understand the structural role of microtubules in vivo, we (Jiaping Zhang and Hanqing Jiang) developed a mechanics model to study microtubule buckling supported by cytoplasm.  We found that the ability for a cell to sustain compressive force does not solely rely on microtubules, but is also supported by the elasticity of cytoplasm. The relatively stiff microtubules and compliant cytoplasm are combined to provide a scaffold for compressive force.