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The CAR that drives Ca2+ to Orai1
1The Epithelial Signaling and Transport Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA.
Science Signaling
|March 10, 2016
Summary
Researchers discovered a calcium-accumulating region (CAR) in the Orai1 channel. This finding explains how Orai1 concentrates calcium ions, facilitating calcium influx and selectivity.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Physiology
Background:
- Store-operated calcium (Ca2+) influx is crucial for cellular functions.
- The Orai1 channel is a key component of store-operated Ca2+ entry.
- Understanding Orai1's Ca2+ permeation and selectivity mechanisms is essential.
Purpose of the Study:
- To elucidate how Ca2+ permeates the Orai1 channel.
- To uncover the mechanism behind Orai1's high Ca2+ selectivity.
Main Methods:
- The study involved analyzing the structure and function of the Orai1 channel.
- Researchers identified a specific region within the Orai1 channel structure.
Main Results:
- A Ca2+-accumulating region (CAR) was identified at the extracellular opening of Orai1.
- This CAR concentrates Ca2+ ions at the channel's entrance.
- Concentration of Ca2+ by CAR facilitates channel permeation and enhances selectivity.
Conclusions:
- The identified CAR is critical for Orai1 channel function.
- This mechanism explains how Orai1 achieves high Ca2+ selectivity.
- The findings provide new insights into store-operated calcium influx regulation.
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