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STIM-ORAI interactions that control the CRAC channel
Aparna Gudlur1, Yubin Zhou, Patrick G Hogan
1La Jolla Institute for Allergy & Immunology, La Jolla, California, USA.
Current Topics in Membranes
|July 30, 2013
Summary
Stromal interaction molecule 1 (STIM1) and ORAI1 proteins form the CRAC channel, essential for calcium entry. This chapter details the protein interactions governing CRAC channel function.
Area of Science:
- Cellular Biology
- Molecular Biology
- Biochemistry
Background:
- Store-operated calcium entry (SOCE) is a critical cellular process.
- The CRAC (calcium release-activated calcium) channel mediates SOCE.
- STIM1 and ORAI1 are the core components of the CRAC channel machinery.
Purpose of the Study:
- To elucidate the protein-protein interactions of STIM and ORAI proteins.
- To understand how these interactions regulate CRAC channel activity.
- To provide a focused review on the molecular mechanisms controlling the CRAC channel.
Main Methods:
- This chapter synthesizes existing research findings.
- It focuses on established biochemical and biophysical studies.
- No new experimental data is presented.
Main Results:
- STIM1 acts as a calcium sensor in the endoplasmic reticulum.
- Upon ER calcium depletion, STIM1 undergoes conformational changes and oligomerizes.
- STIM1 then interacts with ORAI1 channels in the plasma membrane, activating calcium influx.
Conclusions:
- The intricate protein-protein interactions between STIM1 and ORAI1 are fundamental to CRAC channel gating.
- Understanding these interactions is key to comprehending calcium signaling.
- Dysregulation of these interactions is implicated in various diseases.
Keywords:
CRAC channelCRAC currentORAI1ORAI3STIM1calciumgatinginteractionmutationproteinstore-operated calcium entrystructureMore Related Videos
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