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Title: Nonlinear dynamics of C–terminal tails in cellular microtubules

Abstract

The mechanical and electrical properties, and information processing capabilities of microtubules are the permanent subject of interest for carrying out experiments in vitro and in silico, as well as for theoretical attempts to elucidate the underlying processes. In this paper, we developed a new model of the mechano–electrical waves elicited in the rows of very flexible C–terminal tails which decorate the outer surface of each microtubule. The fact that C–terminal tails play very diverse roles in many cellular functions, such as recruitment of motor proteins and microtubule–associated proteins, motivated us to consider their collective dynamics as the source of localized waves aimed for communication between microtubule and associated proteins. Our approach is based on the ferroelectric liquid crystal model and it leads to the effective asymmetric double-well potential which brings about the conditions for the appearance of kink–waves conducted by intrinsic electric fields embedded in microtubules. These kinks can serve as the signals for control and regulation of intracellular traffic along microtubules performed by processive motions of motor proteins, primarly from kinesin and dynein families. On the other hand, they can be precursors for initiation of dynamical instability of microtubules by recruiting the proper proteins responsible for the depolymerization process.

Authors:
; ;  [1];  [2];  [3]
  1. University of Novi Sad, Faculty of Technical Sciences, Novi Sad (Serbia)
  2. University of Belgrade, Institute of Nuclear Sciences Vinca, Belgrade (Serbia)
  3. Laboratory of Radiation Biology, Joint Institute for Nuclear Research, Dubna (Russian Federation)
Publication Date:
OSTI Identifier:
22596556
Resource Type:
Journal Article
Resource Relation:
Journal Name: Chaos (Woodbury, N. Y.); Journal Volume: 26; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 97 MATHEMATICAL METHODS AND COMPUTING; DEPOLYMERIZATION; ELECTRIC FIELDS; ELECTRICAL PROPERTIES; FERROELECTRIC MATERIALS; LIQUID CRYSTALS; MICROTUBULES; NONLINEAR PROBLEMS; PROTEINS

Citation Formats

Sekulic, Dalibor L., E-mail: dalsek@uns.ac.rs, Sataric, Bogdan M., Sataric, Miljko V., Zdravkovic, Slobodan, and Bugay, Aleksandr N. Nonlinear dynamics of C–terminal tails in cellular microtubules. United States: N. p., 2016. Web. doi:10.1063/1.4959802.
Sekulic, Dalibor L., E-mail: dalsek@uns.ac.rs, Sataric, Bogdan M., Sataric, Miljko V., Zdravkovic, Slobodan, & Bugay, Aleksandr N. Nonlinear dynamics of C–terminal tails in cellular microtubules. United States. doi:10.1063/1.4959802.
Sekulic, Dalibor L., E-mail: dalsek@uns.ac.rs, Sataric, Bogdan M., Sataric, Miljko V., Zdravkovic, Slobodan, and Bugay, Aleksandr N. 2016. "Nonlinear dynamics of C–terminal tails in cellular microtubules". United States. doi:10.1063/1.4959802.
@article{osti_22596556,
title = {Nonlinear dynamics of C–terminal tails in cellular microtubules},
author = {Sekulic, Dalibor L., E-mail: dalsek@uns.ac.rs and Sataric, Bogdan M. and Sataric, Miljko V. and Zdravkovic, Slobodan and Bugay, Aleksandr N.},
abstractNote = {The mechanical and electrical properties, and information processing capabilities of microtubules are the permanent subject of interest for carrying out experiments in vitro and in silico, as well as for theoretical attempts to elucidate the underlying processes. In this paper, we developed a new model of the mechano–electrical waves elicited in the rows of very flexible C–terminal tails which decorate the outer surface of each microtubule. The fact that C–terminal tails play very diverse roles in many cellular functions, such as recruitment of motor proteins and microtubule–associated proteins, motivated us to consider their collective dynamics as the source of localized waves aimed for communication between microtubule and associated proteins. Our approach is based on the ferroelectric liquid crystal model and it leads to the effective asymmetric double-well potential which brings about the conditions for the appearance of kink–waves conducted by intrinsic electric fields embedded in microtubules. These kinks can serve as the signals for control and regulation of intracellular traffic along microtubules performed by processive motions of motor proteins, primarly from kinesin and dynein families. On the other hand, they can be precursors for initiation of dynamical instability of microtubules by recruiting the proper proteins responsible for the depolymerization process.},
doi = {10.1063/1.4959802},
journal = {Chaos (Woodbury, N. Y.)},
number = 7,
volume = 26,
place = {United States},
year = 2016,
month = 7
}
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