Encyclopedia of Biophysics

Living Edition
| Editors: Gordon Roberts, Anthony Watts, European Biophysical Societies

Cut-Open Oocyte Voltage-Clamp Technique

  • Antonios Pantazis
  • Riccardo OlceseEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-35943-9_371-1


The cut-open oocyte Vaseline gap (COVG) voltage clamp technique, a relatively recent addition to the electrophysiologist’s armamentarium, was specifically developed by Drs. Stefani and Bezanilla (Bezanilla et al. 1991) to achieve low-noise recordings of the membrane of Xenopus laevis oocytes with fast clamp speed and thus optimize the most popular transient expression system to reveal the activity voltage-dependent proteins previously difficult to resolve by alternative methods. The high degree of specialization of this technique is complemented by its flexibility; in addition to oocyte perfusion, COVG can be combined with optical measurements (voltage clamp fluorometry and spectroscopy) and flash photolysis for the instantaneous release of intracellular caged compounds, expanding its use beyond electrophysiology.

Historical Points

During the cloning era, the oocytes of the African clawed frog (Xenopus laevis) emerged as a powerful biological tool, as their large size (≈1...

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Copyright information

© European Biophysical Societies' Association (EBSA) 2019

Authors and Affiliations

  1. 1.Division of Molecular Medicine, Department of Anesthesiology & Perioperative MedicineUniversity of California at Los AngelesLos AngelesUSA
  2. 2.Division of Neurobiology, Department of Clinical and Experimental Medicine (IKE)Linköping UniversityLinköpingSweden
  3. 3.Wallenberg Center for Molecular MedicineLinköping UniversityLinköpingSweden
  4. 4.Department of Physiology, David Geffen School of MedicineUniversity of California at Los AngelesLos AngelesUSA
  5. 5.Brain Research InstituteUniversity of California at Los AngelesLos AngelesUSA
  6. 6.Cardiovascular Research Laboratories, David Geffen School of MedicineUniversity of California at Los AngelesLos AngelesUSA