Computational Study of the Electrostatic Coupling of Membrane-spanning α-Helices Controlled by Dielectric Media

Tarunendu Mapder, Lipika Adhya

Abstract

Voltage-gated potassium ion-channels (Kv) play a key role in neurons. The ion-channel is a tetramer each having two domains: voltage senor-domain (VSD) and pore-domain (PD), with four (S1-S4) and two (S5-S6) α-helices respectively, which behave like macrodipoles. The VSD appears capable of adopting different orientations relative to the pore-domain of Kv channels in response to the variable (-70V to +30V) transmembrane-voltage controlling the passage-way of the K+ ions across the membrane. There is an immense progress in the study of voltage-gated channel; however the molecular mechanism underlying voltage sensing is still a matter of debate. Here, we have used a novel theoretical approach using electrostatic theory to identify the possible stable conformation of the voltage gated potassium ion-channel of Aeropyrum pernix (KvAP) at zero transmembrane-voltage by computing the minimum potential energy of the system embedded in hybrid dielectric environment. We have set up an algorithm to generate data, which is presented graphically and then analyzed to study the configuration of the biological system of KvAP. It is observed that in ion-channel protein two adjacent α-helices behaving like a macrodipole conform to antiparallel arrangement and the involvement of the charged residues with the multidielectric environment gives the ion-channel protein different conformations.

References

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Paper Citation


in Harvard Style

Mapder T. and Adhya L. (2013). Computational Study of the Electrostatic Coupling of Membrane-spanning α-Helices Controlled by Dielectric Media . In Proceedings of the International Conference on Bioinformatics Models, Methods and Algorithms - Volume 1: BIOINFORMATICS, (BIOSTEC 2013) ISBN 978-989-8565-35-8, pages 111-115. DOI: 10.5220/0004193601110115


in Bibtex Style

@conference{bioinformatics13,
author={Tarunendu Mapder and Lipika Adhya},
title={Computational Study of the Electrostatic Coupling of Membrane-spanning α-Helices Controlled by Dielectric Media},
booktitle={Proceedings of the International Conference on Bioinformatics Models, Methods and Algorithms - Volume 1: BIOINFORMATICS, (BIOSTEC 2013)},
year={2013},
pages={111-115},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0004193601110115},
isbn={978-989-8565-35-8},
}


in EndNote Style

TY - CONF
JO - Proceedings of the International Conference on Bioinformatics Models, Methods and Algorithms - Volume 1: BIOINFORMATICS, (BIOSTEC 2013)
TI - Computational Study of the Electrostatic Coupling of Membrane-spanning α-Helices Controlled by Dielectric Media
SN - 978-989-8565-35-8
AU - Mapder T.
AU - Adhya L.
PY - 2013
SP - 111
EP - 115
DO - 10.5220/0004193601110115