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Updated: Aug 3, 2026
10:05
In Vitro Analysis of PDZ-dependent CFTR Macromolecular Signaling Complexes
Published on: August 13, 2012
Functional interaction between CFTR and Cx45 gap junction channels expressed in oocytes
1Department of Pharmacology and Physiology, University of Rochester School of Medicine, NY 14642-8711, USA.
The Journal of Membrane Biology
|June 30, 2005
Summary
Cystic fibrosis transmembrane conductance regulator (CFTR) influences connexin45 (Cx45) gap junction channels. CFTR reduces Cx45 channel voltage sensitivity, impacting cell-to-cell communication.
Area of Science:
- Molecular biology
- Cellular physiology
- Ion channel function
Background:
- The cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride channel.
- CFTR is known to modulate the function of other ion channels, including connexin channels.
Purpose of the Study:
- To investigate the functional interaction between CFTR and connexin45 (Cx45) gap junction channels.
- To determine how CFTR affects Cx45 channel conductance and voltage sensitivity.
Main Methods:
- Co-expression of CFTR and Cx45 in Xenopus oocytes.
- Dual voltage clamp electrophysiology to monitor junctional conductance and voltage sensitivity.
- Application of forskolin to modulate cAMP levels and diphenylamine carboxylic acid as a CFTR blocker.
Main Results:
- Forskolin application in oocytes co-expressing CFTR and Cx45 increased junctional conductance (G(j)).
- CFTR presence reduced the transjunctional voltage sensitivity of Cx45 channels.
- Forskolin further enhanced the reduction in voltage sensitivity.
Conclusions:
- CFTR significantly influences cell-to-cell coupling mediated by Cx45 channels.
- CFTR's interaction with Cx45 affects gap junction channel gating properties.
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