Calreticulin: Endoplasmic reticulum Ca2+ gatekeeper
1Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.
Journal of Cellular and Molecular Medicine
|July 10, 2023
Summary
Calreticulin, an endoplasmic reticulum (ER) protein, is crucial for managing calcium (Ca2+) levels and signaling. Its proper function is vital for cellular health and preventing diseases linked to calcium imbalance.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Medicine
Background:
- Endoplasmic reticulum (ER) luminal calcium (Ca2+) is essential for cellular function and signaling.
- Calreticulin is a key ER-resident protein involved in Ca2+ homeostasis and chaperone activity.
Purpose of the Study:
- To elucidate the multifaceted roles of calreticulin in regulating ER luminal Ca2+.
- To highlight calreticulin's function as an ER Ca2+ sensor and its impact on cellular processes.
Main Methods:
- Review of established research on calreticulin's structure and function.
- Analysis of calreticulin's interactions with Ca2+ handling molecules and substrates.
- Examination of calreticulin's role in Ca2+-dependent cellular events.
Main Results:
- Calreticulin critically maintains ER Ca2+ supply, access, and utilization under various physiological conditions.
- It acts as an ER luminal Ca2+ sensor, managing Ca2+-dependent events and interactions within the ER.
- Calreticulin influences cellular processes beyond the ER, impacting broader cellular pathophysiology.
Conclusions:
- Calreticulin is indispensable for ER Ca2+ homeostasis and cellular signaling.
- Dysregulation of ER Ca2+ handling by calreticulin is implicated in numerous pathologies, including heart failure, neurodegeneration, and metabolic diseases.
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