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Updated: Jul 15, 2026
10:46
Mechanical Stimulation-induced Calcium Wave Propagation in Cell Monolayers: The Example of Bovine Corneal Endothelial Cells
Published on: July 16, 2013
SRC utilizes Cas to block gap junctional communication mediated by connexin43.
Yongquan Shen1, P Raaj Khusial, Xun Li
1Department of Molecular Biology, Science Center, University of Medicine and Dentistry, Stratford, New Jersey 08084, USA.
The Journal of Biological Chemistry
|May 10, 2007
Summary
Src tyrosine kinase uses Cas to inhibit gap junction communication mediated by connexin43 (Cx43), a novel mechanism potentially explaining suppressed communication in aggressive tumors.
Area of Science:
- Cell Biology
- Molecular Oncology
- Biochemistry
Background:
- Gap junctional communication is reduced in aggressive tumor cells.
- Connexin43 (Cx43) is a tumor suppressor that inhibits cell growth.
- Src tyrosine kinase phosphorylates Cx43, potentially blocking gap junction communication.
Purpose of the Study:
- To elucidate the mechanism by which Src inhibits Cx43-mediated gap junctional communication.
- To investigate the role of Crk-associated substrate (Cas) in this process.
Main Methods:
- Co-immunoprecipitation to detect protein-protein interactions.
- Dye transfer assays to measure gap junctional communication.
- Electrical coupling measurements.
Main Results:
- Src and Cas associate at intercellular junctions.
- Cas is essential for Src to reduce dye transfer and electrical coupling in Cx43-expressing cells.
- Src utilizes Cas to inhibit Cx43-mediated gap junctional communication.
Conclusions:
- Src inhibits gap junctional communication via Cx43 by utilizing the Cas protein.
- Cas plays a novel role in the gap junction complex.
- This mechanism may explain suppressed gap junctional communication in malignant and metastatic tumor cells.
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