Calcium, a signaling molecule in the endoplasmic reticulum?
1MRC Group in Molecular Biology of Membranes and the Department of Biochemistry, University of Alberta, Edmonton, AL, Canada T6G 2H7.
Trends in Biochemical Sciences
|June 29, 2000
Summary
Calcium ions (Ca2+) are vital signaling molecules in the cell cytosol. Emerging evidence indicates Ca2+ also signals within the endoplasmic reticulum, impacting its functions like protein synthesis.
Area of Science:
- Cellular Biology
- Molecular Signaling
Background:
- Calcium ions (Ca2+) are established signaling molecules in the cell cytosol.
- Recent research suggests a signaling role for Ca2+ within the endoplasmic reticulum (ER).
Purpose of the Study:
- To explore the emerging evidence for Ca2+ signaling within the endoplasmic reticulum.
- To understand how ER Ca2+ fluctuations impact cellular functions.
Main Methods:
- Review of existing literature on Ca2+ signaling.
- Analysis of studies investigating ER Ca2+ dynamics.
Main Results:
- Agonist-induced changes in free Ca2+ concentration in the ER are observed.
- These ER Ca2+ fluctuations influence ER functions.
Conclusions:
- Calcium ions play a dual signaling role, in both the cytosol and the endoplasmic reticulum.
- ER Ca2+ signaling is critical for protein synthesis, modification, and chaperone interactions.
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