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Ca(2+) transfer from the ER to mitochondria: when, how and why
Rosario Rizzuto1, Saverio Marchi, Massimo Bonora
1Dept. Biomedical Sciences, University of Padua, Via Colombo 3, Padua 35121, Italy. rosario.rizzuto@unipd.it
Biochimica Et Biophysica Acta
|April 4, 2009
Summary
Mitochondria rapidly increase their calcium levels following cellular calcium rises, primarily due to their proximity to endoplasmic reticulum calcium channels. This highlights a crucial, previously underestimated role for mitochondria in cellular calcium signaling.
Area of Science:
- Cell Biology
- Biochemistry
- Physiology
Background:
- Cellular stimuli trigger complex spatial and temporal calcium signals, influencing diverse cellular functions.
- Mitochondria's role in calcium signaling was historically underestimated due to measurement challenges.
Purpose of the Study:
- To review the molecular mechanisms of calcium transfer between the endoplasmic reticulum and mitochondria.
- To explore the structural basis of organelle contact sites and their impact on mitochondrial calcium uptake.
- To discuss the functional outcomes of mitochondrial calcium increases and the influence of oncogenes.
Main Methods:
- Review of current literature on mitochondrial and ER calcium channels.
- Analysis of structural and molecular data on organelle interactions.
- Examination of studies on the functional consequences of mitochondrial calcium.
Main Results:
- Mitochondrial matrix calcium ([Ca(2+)]m) rapidly rises following cytosolic calcium ([Ca(2+)]c) increases.
- Close proximity between mitochondria and endoplasmic reticulum (ER) calcium channels is critical for rapid mitochondrial calcium uptake.
- Oncogenes can significantly impact mitochondrial calcium homeostasis.
Conclusions:
- Mitochondria play a vital, dynamic role in cellular calcium signaling, particularly through their interaction with the ER.
- Further molecular investigation is required to fully elucidate the intricacies of calcium signaling involving mitochondria and the ER.
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