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Updated: Jun 20, 2026
10:46
Mechanical Stimulation-induced Calcium Wave Propagation in Cell Monolayers: The Example of Bovine Corneal Endothelial Cells
Published on: July 16, 2013
Heterotypic gap junction channels as voltage-sensitive valves for intercellular signaling
Nicolas Palacios-Prado1, Feliksas F Bukauskas
1Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
Summary
Connexin 43/45 (Cx43/Cx45) gap junctions show voltage-dependent gating and dye transfer asymmetries. Cell communication is modulated by transjunctional voltage, impacting development and regeneration.
Area of Science:
- Cell Biology
- Biophysics
- Physiology
Background:
- Gap junctions (GJ) facilitate direct cell-cell communication via connexin (Cx) proteins.
- Cx43 and Cx45 form heterotypic GJs with distinct properties.
Purpose of the Study:
- To investigate the voltage-dependent gating and dye transfer asymmetries in Cx43/Cx45 heterotypic GJs.
- To understand how transjunctional voltage modulates intercellular communication.
Main Methods:
- Combined fluorescence imaging and dual whole-cell voltage clamp.
- Applied ionophoresis of charged fluorescent dyes.
- Utilized transjunctional voltage pulses mimicking action potentials.
Main Results:
- Cx43/Cx45 heterotypic GJs exhibit Vj-gating and dye transfer asymmetries.
- Dye transfer is sensitive to resting potentials and Vj pulse patterns.
- Asymmetry is modulated by synergistic or antagonistic effects of ionophoresis and Vj-gating.
Conclusions:
- Transjunctional voltage significantly modulates intercellular signaling through Cx43/Cx45 GJs.
- This modulation is crucial for embryonic development, adult tissue function, and regeneration.
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