Intrinsic Bending of Microtubule Protofilaments

Department of Chemistry, James Franck Institute, and Computation Institute, University of Chicago, 5735 S. Ellis Avenue, Chicago, IL 60637, USA.
Structure (Impact Factor: 5.62). 03/2011; 19(3):409-17. DOI: 10.1016/j.str.2010.12.020
Source: PubMed


The complex polymerization dynamics of the microtubule (MT) plus end are closely linked to the hydrolysis of the GTP nucleotide bound to the β-tubulin. The destabilization is thought to be associated with the conformational change of the tubulin dimers from the straight conformation in the MT lattice to a curved conformation. It remains under debate whether this transformation is directly related to the nucleotide state, or a consequence of the longitudinal or lateral contacts in the MT lattice. Here, we present large-scale atomistic simulations of short tubulin protofilaments with both nucleotide states, starting from both extreme conformations. Our simulations indicate that both interdimer and intradimer contacts in both GDP and GTP-bound tubulin dimers and protofilaments in solution bend. There are no observable differences between the mesoscopic properties of the contacts in GTP and GDP-bound tubulin or the intradime and interdimer interfaces.

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