Fluorescent Labeling for Patch-Clamp Fluorometry (PCF) Measurements of Real-Time Protein Motion in Ion Channels

  • Thomas K. BergerEmail author
  • Ehud Y. IsacoffEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1266)


Understanding the function of ion channels is a major goal of molecular neurophysiology. While standard electrophysiological methods are invaluable tools to investigate the gating of ion channels, the structural rearrangements that mediate the way a channel senses physiological signals and opens and closes its gates cannot be measured electrically in a direct way. Here, we describe a method, based on site-specific labeling of a channel of interest with an environmentally sensitive fluorophore, which makes it possible to monitor conformational changes of ion channels in biological membranes in real time.

Key words

Patch-clamp fluorometry (PCF) Voltage-clamp fluorometry (VCF) Ion channels Structural dynamics Cysteine-reactive probes Environmentally sensitive fluorophores 



This work was supported by NIH grant R01 NS35549 (E.Y.I.), and a postdoctoral fellowship of the Swiss National Science Foundation (SNSF, PA00P3_134163) (T.K.B.).


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Research Center CaesarBonnGermany
  2. 2.Department of Molecular and Cell Biology and Helen Wills Neuroscience InstituteUniversity of California BerkeleyBerkeleyUSA
  3. 3.Physical Bioscience DivisionLawrence Berkeley National LaboratoryBerkeleyUSA

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