Structural and Functional Analysis of Sodium Channels Viewed from an Evolutionary Perspective
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Updated: Feb 20, 2026

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Published on: June 2, 2023
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.
Abstract:
Voltage-gated sodium channels initiate and propagate action potentials in excitable cells. They respond to membrane depolarization through opening, followed by fast inactivation that terminates the sodium current. This ON-OFF behavior of voltage-gated sodium channels underlays the coding of information and its transmission from one location in the nervous system to another. In this review, we explore and compare structural and functional data from prokaryotic and eukaryotic channels to infer the effects of evolution on sodium channel structure and function.
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