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Updated: Jul 15, 2026
12:05
Production of Disulfide-stabilized Transmembrane Peptide Complexes for Structural Studies
Published on: March 6, 2013
Three-dimensional structure of a recombinant gap junction membrane channel.
V M Unger1, N M Kumar, N B Gilula
1The Scripps Research Institute, Department of Cell Biology, 10550 North Torrey Pines Road, Division of Cardiovascular Diseases, Scripps Clinic, 10666 North Torrey Pines Road, La Jolla, CA 92037, USA.
Science (New York, N.Y.)
|February 19, 1999
Summary
Researchers determined the structure of cardiac gap junction channels using electron crystallography. This revealed a dodecameric channel structure crucial for cell-to-cell communication.
Area of Science:
- Structural biology
- Cell biology
- Biophysics
Background:
- Gap junction channels are essential for intercellular communication, mediating electrical and metabolic coupling.
- Understanding their structure is key to comprehending cellular function and dysfunction.
Purpose of the Study:
- To determine the high-resolution structure of a recombinant cardiac gap junction channel.
- To elucidate the structural basis of gap junction channel function.
Main Methods:
- Electron crystallography was employed to resolve the channel structure.
- The study achieved resolutions of 7.5 Å in the membrane plane and 21 Å vertically.
Main Results:
- The cardiac gap junction channel was identified as a dodecamer, formed by two hexameric connexons.
- Electron density revealed four transmembrane alpha-helical domains per connexin subunit.
- Extracellular domains formed a tight seal, preventing substance exchange with the extracellular environment.
Conclusions:
- The determined structure provides insights into the molecular organization of cardiac gap junctions.
- The alpha-helical transmembrane domains likely facilitate channel pore formation.
- The sealed extracellular vestibule suggests a role in regulating channel selectivity and function.
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