Article thumbnail

Metastability of Microtubules Induced by Competing Internal Forces

By Viktória Hunyadi and Imre M. Jánosi


AbstractRecent modeling efforts to estimate energies of tubulin-tubulin bonds shed light on a delicate balance between competing mechanical forces maintaining microtubule walls. Here we formulate two important refinements to the explanation of bond energetics. First, energy surface calculations in the elastic filament approximation reveal a finite stabilizing barrier assumed a simple Lennard-Jones-like potential for protein bonds. The presence of a guanosine triphosphate (GTP) cap represented by straight segments is necessary, as it is predicted for a long time. In the lack of such a cap, the protofilaments are either in an absolutely stable or absolutely unstable state. Second, our calculations show that this barrier appears only if the mechanical energy associated with the conformational change after GTP hydrolysis (curling energy) is larger than the strength of lateral bonds. The overall energy balance we propose supports continuous assembly of GTP dimers, a metastable state in the presence of a finite GTP cap and energetically driven disassembly of guanosine diphosphate protofilaments

Publisher: The Biophysical Society. Published by Elsevier Inc.
Year: 2007
DOI identifier: 10.1529/biophysj.106.091793
OAI identifier:
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • https://s3-eu-west-1.amazonaws... (external link)
  • (external link)
  • Suggested articles

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.