Microtubule Mechanics

Microtubules are hollow protein polymers from the cytoskeleton, a network of filaments that provides the cell with mechanical integrity and is involved in a plethora of important cell functions. The polymers consists of dimers made of alpha- and beta-tubulin, here shown in red and orange. Dimers form chains called protofilaments, and the protofilaments arrange in a circle to form a tube with a diameter of ~25nm. freeMTBecause of their anisotropic architecture, microtubules have mechanical properties that are a lot more complex than the predictions of simple polymer models. Most significantly, their stiffness depends on their length! Shorter microtubules are actually much softer than measurements on longer microtubules would suggest. The reason is that when microtubules deform, their protofilaments can slide past one another and make the response much softer [Pampaloni, 2006].

The length-dependent stiffness also affects the timescales of microtubule thermal shape fluctuations. Because short microtubules are softer than expected, they also fluctuate more slowly [Taute, 2008] .


  • Katja M. Taute, Francesco Pampaloni, and Ernst-Ludwig Florin. “Extracting the mechanical properties of microtubules from thermal fluctuation measurements on an attached tracer particle”. Methods in Cell Biology, Vol. 95: “Microtubules, In Vitro”. Chapter 30, 601-615.
  • Francesco Pampaloni and Ernst-Ludwig Florin. “Microtubule architecture: Inspiration for novel carbon nanotube-based biomimetic materials”. Trends in Biotechnology 26(6):302-310, 2008. pdf
  • Katja M. Taute, Francesco Pampaloni, Erwin Frey, Ernst-Ludwig Florin. ‘Microtubule dynamics depart from the wormlike chain model’?. Phys. Rev. Lett. 100:028101, 2008. pdf
  • Francesco Pampaloni, Gianluca Lattanzi, Alexandr Jonas, Thomas Surrey, Erwin Frey, and Ernst-Ludwig Florin. “Thermal fluctuations of microtubules provide evidence of a length-dependent persistence length”. PNAS 103(27):10248-53, 2006. pdf


Prof. Dr. Erwin Frey ‘  Ludwig-Maximillian University Munich – Arnold Sommerfeld Center for Theoretical Physics

Dr. Francesco Pampaloni ‘  Johann Wolfgang Goethe University Frankfurt – Frankfurt Institue for Molecular Life Science

Dr. Thomas Surrey ‘  Cancer Research UK London Research Institute


NSF grants   CMMI-0728166   and   CMMI-1031106.