Summary
Ion channels are the cell's gatekeepers. These proteins selectively allow ionic current to flow down its electrochemical gradient. In some cases, specialized chemical or voltage sensing domains respond to environmental changes and signal the cell to adjust its internal chemistry in response to its surroundings. Because of their importance in cell function, channels have been the focus of intense study at the functional and structural level. Here we describe the optical technique voltage-clamp fluorometry (VCF) which is used to monitor the functional state and probe the structural rearrangements that take place as ion channels are activated by voltage. VCF combines electrophysiology, molecular biology, chemistry, and fluorescence into a single technique. Our focus is on voltage-gated ion channels, but the technique described can be applied to other proteins. We describe the cut open vaseline gap configuration (COVG) for VCF recording.
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Acknowledgments
We thank Medha Pathak, Sandra Wiese, Nicoletta Savalli, and members of the Olcese and Isacoff laboratories for helpful suggestions.
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© 2008 Humana Press 2008, a part of Springer Science+Business Media, LLC
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Gandhi, C.S., Olcese, R. (2008). The Voltage-Clamp Fluorometry Technique. In: Lippiat, J.D. (eds) Potassium Channels. Methods in Molecular Biology, vol 491. Humana Press. https://doi.org/10.1007/978-1-59745-526-8_17
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DOI: https://doi.org/10.1007/978-1-59745-526-8_17
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