Chapter title |
From Stores to Sinks: Structural Mechanisms of Cytosolic Calcium Regulation
|
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Chapter number | 10 |
Book title |
Membrane Dynamics and Calcium Signaling
|
Published in |
Advances in experimental medicine and biology, January 2017
|
DOI | 10.1007/978-3-319-55858-5_10 |
Pubmed ID | |
Book ISBNs |
978-3-31-955857-8, 978-3-31-955858-5
|
Authors |
Masahiro Enomoto, Tadateru Nishikawa, Naveed Siddiqui, Steve Chung, Mitsuhiko Ikura, Peter B. Stathopulos, Enomoto, Masahiro, Nishikawa, Tadateru, Siddiqui, Naveed, Chung, Steve, Ikura, Mitsuhiko, Stathopulos, Peter B. |
Abstract |
All eukaryotic cells have adapted the use of the calcium ion (Ca2+) as a universal signaling element through the evolution of a toolkit of Ca2+ sensor, buffer and effector proteins. Among these toolkit components, integral and peripheral proteins decorate biomembranes and coordinate the movement of Ca2+ between compartments, sense these concentration changes and elicit physiological signals. These changes in compartmentalized Ca2+ levels are not mutually exclusive as signals propagate between compartments. For example, agonist induced surface receptor stimulation can lead to transient increases in cytosolic Ca2+ sourced from endoplasmic reticulum (ER) stores; the decrease in ER luminal Ca2+ can subsequently signal the opening surface channels which permit the movement of Ca2+ from the extracellular space to the cytosol. Remarkably, the minuscule compartments of mitochondria can function as significant cytosolic Ca2+ sinks by taking up Ca2+ in a coordinated manner. In non-excitable cells, inositol 1,4,5 trisphosphate receptors (IP3Rs) on the ER respond to surface receptor stimulation; stromal interaction molecules (STIMs) sense the ER luminal Ca2+ depletion and activate surface Orai1 channels; surface Orai1 channels selectively permit the movement of Ca2+ from the extracellular space to the cytosol; uptake of Ca2+ into the matrix through the mitochondrial Ca2+ uniporter (MCU) further shapes the cytosolic Ca2+ levels. Recent structural elucidations of these key Ca2+ toolkit components have improved our understanding of how they function to orchestrate precise cytosolic Ca2+ levels for specific physiological responses. This chapter reviews the atomic-resolution structures of IP3R, STIM1, Orai1 and MCU elucidated by X-ray crystallography, electron microscopy and NMR and discusses the mechanisms underlying their biological functions in their respective compartments within the cell. |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
Unknown | 14 | 100% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Researcher | 4 | 29% |
Student > Doctoral Student | 1 | 7% |
Student > Bachelor | 1 | 7% |
Student > Ph. D. Student | 1 | 7% |
Professor | 1 | 7% |
Other | 2 | 14% |
Unknown | 4 | 29% |
Readers by discipline | Count | As % |
---|---|---|
Biochemistry, Genetics and Molecular Biology | 3 | 21% |
Pharmacology, Toxicology and Pharmaceutical Science | 1 | 7% |
Agricultural and Biological Sciences | 1 | 7% |
Immunology and Microbiology | 1 | 7% |
Medicine and Dentistry | 1 | 7% |
Other | 2 | 14% |
Unknown | 5 | 36% |