Related Experiment Video
Updated: Oct 8, 2026

Functional Reconstitution and Channel Activity Measurements of Purified Wildtype and Mutant CFTR Protein
Published on: March 9, 2015
A src-like kinase activates outwardly rectifying chloride channels in CFTR-defective lymphocytes
A Lepple-Wienhues1, U Wieland, T Laun
1Department for Physiology, University of Tübingen, Tübingen, Germany. alepplew@uni-tuebingen.de
Abstract:
Defective activation of chloride channels is a hallmark of cystic fibrosis (CF). Recently we have described activation of a volume-sensitive, outwardly rectifying chloride conductance (I(OR)) through the src-like tyrosine kinase p56(lck). Here we show that p56(lck) activates I(OR) independently of CFTR. In lymphocytes from healthy donors, chloride channels could be opened by either intracellular cAMP, p56(lck) or osmotic swelling. In CF lymphocytes, p56(lck) and cell swelling but not cAMP could activate chloride channels. Regulation of I(OR) by p56(lck) thus represents an alternative pathway of stimulating membrane chloride conductance that is left intact in cystic fibrosis.
Related Concept Videos
Receptor Tyrosine Kinases
GPCRs Regulate Adenylyl Cylase Activity
Two...
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...
Mechanically-gated Ion Channels
Amplifying Signals via Enzymatic Cascade
Receptor Downregulation in MVBs
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...

