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Updated: Jun 2, 2026
05:52
Reconstitution of Msp1 Extraction Activity with Fully Purified Components
Published on: August 10, 2021
STIM proteins and the endoplasmic reticulum-plasma membrane junctions
Silvia Carrasco1, Tobias Meyer
1Department of Chemical and Systems Biology, School of Medicine, Stanford University, Stanford, California 94305, USA. silviac2@stanford.edu
Annual Review of Biochemistry
|May 10, 2011
Summary
Endoplasmic reticulum-plasma membrane (ER-PM) junctions facilitate direct communication between organelles. Recent research highlights their crucial roles in calcium signaling and lipid transfer.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Eukaryotic organelles interact via membrane junctions, with ER-PM junctions offering direct ER-PM communication.
- These junctions are critical for cellular signaling and metabolic regulation, including calcium (Ca2+) and lipid transfer.
Purpose of the Study:
- To provide a broad perspective on the structures and functions of ER-PM junctions.
- To synthesize recent research on the roles of ER-PM junctions in Ca2+ signaling and lipid metabolism.
Main Methods:
- Literature review integrating findings from diverse research fields.
- Analysis of signaling pathways involving STIM proteins, Orai channels, and ryanodine receptors.
Main Results:
- ER-PM junctions mediate STIM-dependent Orai activation for Ca2+ influx.
- Inverse signaling involves voltage-gated Ca2+ channels regulating ER ryanodine receptors in muscle cells.
- These junctions are vital for cholesterol and phosphatidylinositol lipid transfer.
Conclusions:
- ER-PM junctions are essential communication hubs with significant roles in Ca2+ homeostasis and lipid metabolism.
- Understanding ER-PM junction structure and function is key to deciphering cellular signaling and metabolic control.
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