Design and characterization of a DNA-encoded, voltage-sensitive fluorescent protein

Eur J Neurosci. 2001 Jun;13(12):2314-8. doi: 10.1046/j.0953-816x.2001.01617.x.


Optical imaging of electrical activity has been suggested as a promising approach to investigate the multineuronal representation of information processing in brain tissue. While considerable progress has been made in the development of instrumentation suitable for high-speed imaging, intrinsic or extrinsic dye-mediated optical signals are often of limited use due to their slow response dynamics, low effective sensitivity, toxicity or undefined cellular origin. Protein-based and DNA-encoded voltage sensors could overcome these limitations. Here we report the design and generation of a voltage-sensitive fluorescent protein (VSFP) consisting of a voltage sensing domain of a potassium channel and a pair of cyan and yellow emitting mutants of green fluorescent protein (GFP). In response to a change in transmembrane voltage, the voltage sensor alters the amount of fluorescence resonance energy transfer (FRET) between the pair of GFP mutants. The optical signals respond in the millisecond time-scale of fast electrical signalling and are large enough to allow monitoring of voltage changes at the single cell level.

MeSH terms

  • Action Potentials / drug effects*
  • Action Potentials / physiology
  • Animals
  • Brain / cytology
  • Brain / drug effects
  • Brain / metabolism
  • Cell Membrane / drug effects
  • Cell Membrane / metabolism
  • Cells, Cultured
  • DNA / chemical synthesis
  • DNA / genetics*
  • Electronic Data Processing
  • Electrophysiology
  • Green Fluorescent Proteins
  • Humans
  • Luminescent Proteins / chemical synthesis
  • Luminescent Proteins / genetics*
  • Microscopy, Fluorescence
  • Mutation / physiology
  • Neurons / cytology
  • Neurons / drug effects*
  • Neurons / metabolism
  • Neurophysiology
  • Photochemistry
  • Potassium Channels / chemical synthesis
  • Potassium Channels / genetics*
  • Protein Engineering / methods*
  • Protein Structure, Tertiary / genetics


  • Luminescent Proteins
  • Potassium Channels
  • Green Fluorescent Proteins
  • DNA