https://doi.org/10.1140/epje/i2011-11049-0
Nonlinear ionic pulses along microtubules
1
Faculty of Technical Sciences, University of Novi Sad, Trg D. Obradovića 6, 21000, Novi Sad, Serbia
2
Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Alberta, Canada
3
Department of Physics, University of Alberta, Edmonton, Alberta, Canada
* e-mail: dalsek@yahoo.com
Received:
27
December
2010
Revised:
24
March
2011
Accepted:
11
April
2011
Published online:
23
May
2011
Microtubules are cylindrically shaped cytoskeletal biopolymers that are essential for cell motility, cell division and intracellular trafficking. Here, we investigate their polyelectrolyte character that plays a very important role in ionic transport throughout the intra-cellular environment. The model we propose demonstrates an essentially nonlinear behavior of ionic currents which are guided by microtubules. These features are primarily due to the dynamics of tubulin C-terminal tails which are extended out of the surface of the microtubule cylinder. We also demonstrate that the origin of nonlinearity stems from the nonlinear capacitance of each tubulin dimer. This brings about conditions required for the creation and propagation of solitonic ionic waves along the microtubule axis. We conclude that a microtubule plays the role of a biological nonlinear transmission line for ionic currents. These currents might be of particular significance in cell division and possibly also in cognitive processes taking place in nerve cells.
© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg, 2011