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Structural and Functional Analysis of Sodium Channels Viewed from an Evolutionary Perspective
Tamer M Gamal El-Din1, Michael J Lenaeus2, William A Catterall2
1Department of Pharmacology, University of Washington, Seattle, WA, 98195-7280, USA. tmgamal@uw.edu.
Handbook of Experimental Pharmacology
|October 19, 2017
Summary
Voltage-gated sodium channels control nerve signal transmission via ON-OFF behavior. This review compares prokaryotic and eukaryotic channels to understand how evolution shaped their structure and function.
Area of Science:
- Neuroscience
- Molecular Biology
- Biophysics
Background:
- Voltage-gated sodium channels (VGSCs) are crucial for action potential generation and propagation in excitable cells.
- Their function relies on a precise ON-OFF gating mechanism involving channel opening and rapid inactivation.
- This dynamic behavior underpins neural information coding and transmission.
Purpose of the Study:
- To review and compare structural and functional data of prokaryotic and eukaryotic voltage-gated sodium channels.
- To infer the evolutionary impact on the structure and function of these essential ion channels.
Main Methods:
- Comparative analysis of existing structural and functional data from diverse sodium channel types.
- Literature review focusing on both prokaryotic and eukaryotic channel research.
Main Results:
- Evolution has significantly influenced the structural motifs and functional properties of sodium channels.
- Prokaryotic and eukaryotic channels share conserved gating mechanisms but exhibit divergent regulatory elements.
- Comparative analysis reveals key adaptations related to voltage sensing, ion permeation, and inactivation.
Conclusions:
- Understanding the evolutionary trajectory of sodium channels provides insights into their diverse roles in physiology and disease.
- Comparative studies highlight conserved principles and unique adaptations in ion channel evolution.
- Further research integrating structural and functional data will refine our understanding of sodium channel diversification.
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