Abstract
The detection of electrical potentials across lipid bilayers by specialized membrane proteins is required for many fundamental cellular processes such as the generation and propagation of nerve impulses. These membrane proteins possess modular voltage-sensing domains, a notable example being the S1–S4 domains of voltage-activated ion channels. Ground-breaking structural studies on these domains explain how voltage sensors are designed and reveal important interactions with the surrounding lipid membrane. Although further structures are needed to understand the conformational changes that occur during voltage sensing, the available data help to frame several key concepts that are fundamental to the mechanism of voltage sensing.
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Acknowledgements
I thank J. Diamond, J. Mindell, S. Silberberg and the members of the Swartz laboratory for discussions. I thank R. MacKinnon for providing coordinates for the paddle-chimera and those for the superimposed structures shown in Fig. 3. This work was supported by the Intramural Research Program of the NINDS, NIH.
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Swartz, K. Sensing voltage across lipid membranes. Nature 456, 891–897 (2008). https://doi.org/10.1038/nature07620
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DOI: https://doi.org/10.1038/nature07620
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