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Updated: May 9, 2026
09:32
Direct Imaging of ER Calcium with Targeted-Esterase Induced Dye Loading (TED)
Published on: May 7, 2013
Structure and function of endoplasmic reticulum STIM calcium sensors
Peter B Stathopulos1, Mitsuhiko Ikura
1Department of Medical Biophysics and Ontario Cancer Institute, University of Toronto and University Health Network, Toronto, Ontario, Canada. pstathop@uhnres.utoronto.ca
Current Topics in Membranes
|July 30, 2013
Summary
Store-operated calcium entry (SOCE) relies on STIM proteins sensing calcium levels and interacting with Orai channels. High-resolution structures reveal STIM-Orai mechanisms crucial for CRAC channel function.
Area of Science:
- Molecular biology
- Cellular physiology
- Structural biology
Background:
- Store-operated calcium entry (SOCE) is a fundamental Ca(2+) signaling pathway essential for numerous cellular functions.
- Stromal interaction molecules (STIMs) regulate SOCE by sensing endoplasmic reticulum Ca(2+) and interacting with Orai channels.
- Dysregulation of SOCE is implicated in various pathophysiological conditions.
Purpose of the Study:
- To elucidate the mechanistic insights into STIM and Orai function in SOCE.
- To highlight the significance of recent atomic resolution structures of STIM and Orai proteins.
- To integrate structural data with biophysical and cellular studies to understand CRAC channel regulation.
Main Methods:
- Analysis of atomic resolution structures of human STIM1/STIM2 and Drosophila melanogaster Orai.
- Biophysical techniques to study protein interactions and channel function.
- Biochemical assays and live cell imaging to validate structural findings.
Main Results:
- High-resolution structures provide critical mechanistic details of STIM protein regulation and Orai channel gating.
- Structural data reveals the atomic composition of the CRAC channel pore and subunit assembly.
- Integration of structural and functional data enhances understanding of STIM-Orai interplay in SOCE.
Conclusions:
- Atomic structures of STIM and Orai proteins offer unprecedented mechanistic understanding of SOCE.
- These structural insights are pivotal for deciphering the regulation of CRAC channels.
- Further research integrating structural and functional data will advance the understanding of calcium signaling pathways.
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