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Kinetic models for stochastically modified ionic channels

Abstract

Ionic channels form pores in biomembranes. These pores are large macromolecular structures. Due to thermal fluctuations of countless degrees-of-freedom of the biomembrane material, the actual form of the pores is permanently subject to modification. Furthermore, the arrival of an ion at the binding site can change this form by repolarizing the surrounding aminoacids. In any case the variations of the pore structure are stochastic. In this paper, we discuss the effect of such modifications on the channel conductivity. Applying a simple kinetic description, we show that stochastic variations in channel properties can significantly alter the ionic current, even leading to its substantial increase or decrease for the specific matching of some time-scales of the system.

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Correspondence to Aleksander Wozinski.

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Paper authored by participants of the international conference: International Workshop on Ionic Channels, Szczyrk, Poland, May 27–June 01, 2007. Publication cost was covered by the organisers of this meeting.

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Wozinski, A., Iwaniszewski, J. Kinetic models for stochastically modified ionic channels. Cell Mol Biol Lett 13, 421–429 (2008). https://doi.org/10.2478/s11658-008-0010-0

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  • DOI: https://doi.org/10.2478/s11658-008-0010-0

Key words

  • Ionic channel
  • Fluctuations
  • Kinetic model
  • Resonant activation