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Updated: Mar 20, 2026

Mechanical Stimulation-induced Calcium Wave Propagation in Cell Monolayers: The Example of Bovine Corneal Endothelial Cells
Published on: July 16, 2013
Surface expression of the Anoctamin-1 (ANO1) channel is suppressed by protein-protein interactions with β-COP
Young-Sun Lee1, Yeonju Bae2, Nammi Park2
1School of Biosystem and Biomedical Science, College of Health Science, Korea University, Seoul 02841, Republic of Korea; Center for Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.
Abstract:
Anoctamin-1 (ANO1) is a Ca(2+)-activated chloride channel (CaCC) that plays important physiological roles in normal and cancerous tissues. However, the plasma membrane trafficking mechanisms of ANO1 remain poorly characterized. In yeast two-hybrid screening experiments, we observed direct interactions of ANO1 with β-COP, which is a subunit of Coat Protein Complex I (COPI). This interaction was then confirmed using several in vitro and in vivo binding assays. Moreover, the cotransfection of β-COP with ANO1 into HEK293T cells led to decreased the surface expression and the channel activity of ANO1. Accordingly, endogenous ANO1 was associated with β-COP in U251 glioblastoma cells, and silencing of β-COP enhanced surface expression and whole-cell currents of ANO1 in these cells. Taken together, these data suggest that β-COP negatively regulates ANO1 surface expression.
Insights
Coat Protein Complex I (COPI) subunit β-COP directly interacts with Anoctamin-1 (ANO1), a calcium-activated chloride channel. This interaction reduces ANO1 surface expression and channel activity, suggesting β-COP negatively regulates ANO1 trafficking.
Area of Science:
- Cell biology
- Ion channel physiology
Background:
- Anoctamin-1 (ANO1) is a calcium-activated chloride channel (CaCC) crucial for physiological functions in various tissues.
- The mechanisms governing ANO1's transport to the plasma membrane are not well understood.
Purpose of the Study:
- To investigate the molecular mechanisms regulating ANO1 plasma membrane trafficking.
- To identify proteins that interact with ANO1 and influence its surface expression.
Main Methods:
- Yeast two-hybrid screening to identify ANO1 interacting proteins.
- In vitro and in vivo binding assays to confirm ANO1-β-COP interaction.
- HEK293T cell cotransfection experiments to assess the impact of β-COP on ANO1.
- Analysis of endogenous ANO1 and β-COP association in U251 glioblastoma cells.
- β-COP silencing experiments to evaluate its effect on ANO1 surface expression and activity.
Main Results:
- Direct interaction between ANO1 and β-COP, a subunit of Coat Protein Complex I (COPI), was identified.
- Co-expression of β-COP with ANO1 reduced ANO1 surface expression and channel activity in HEK293T cells.
- Endogenous ANO1 was found to associate with β-COP in U251 glioblastoma cells.
- Silencing of β-COP led to increased surface expression and whole-cell currents of ANO1 in U251 cells.
Conclusions:
- β-COP directly interacts with ANO1.
- β-COP negatively regulates the surface expression and activity of ANO1.
- These findings elucidate a novel mechanism controlling ANO1 plasma membrane localization and function.
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