Related Experiment Video
Updated: Jul 9, 2026

In Vitro Analysis of PDZ-dependent CFTR Macromolecular Signaling Complexes
Published on: August 13, 2012
CFTR regulates outwardly rectifying chloride channels through an autocrine mechanism involving ATP
E M Schwiebert1, M E Egan, T H Hwang
1Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Abstract:
The cystic fibrosis transmembrane conductance regulator (CFTR) functions to regulate both Cl- and Na+ conductive pathways; however, the cellular mechanisms whereby CFTR acts as a conductance regulator are unknown. CFTR and outwardly rectifying Cl- channels (ORCCs) are distinct channels but are linked functionally via an unknown regulatory mechanism. We present results from whole-cell and single-channel patch-clamp recordings, short-circuit current recordings, and [gamma-32P]ATP release assays of normal, CF, and wild-type or mutant CFTR-transfected CF airway cultured epithelial cells wherein CFTR regulates ORCCs by triggering the transport of the potent agonist, ATP, out of the cell. Once released, ATP stimulates ORCCs through a P2U purinergic receptor-dependent signaling mechanism. Our results suggest that CFTR functions to regulate other Cl- secretory pathways in addition to itself conducting Cl-.
More Related Videos
Related Concept Videos
pH Regulation in Cells
Cytosolic pH
Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
G-Protein Gated Ion Channels
Sensory organs,...
GPCRs Regulate Adenylyl Cylase Activity
Two...
Feedback Regulation of Calcium Concentration
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Cystic Fibrosis: Pathogenesis
CF is primarily caused by a genetic mutation in a chromosome 7 gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The most common gene mutation leading to CF is the ΔF508 mutation, but...
Reabsorption and Secretion in the DCT and Collecting Duct
The distal part of the DCT, along with the...

