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Calcium and mitochondria
Author(s) -
Gunter Thomas E.,
Yule David I.,
Gunter Karlene K.,
Eliseev Roman A.,
Salter Jason D.
Publication year - 2004
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/j.febslet.2004.03.071
Subject(s) - mitochondrion , oxidative phosphorylation , microbiology and biotechnology , endoplasmic reticulum , cytosol , calcium , organelle , mitochondrial permeability transition pore , calcium signaling , chemistry , biology , biochemistry , biophysics , programmed cell death , apoptosis , signal transduction , organic chemistry , enzyme
The literature suggests that the physiological functions for which mitochondria sequester Ca 2+ are (1) to stimulate and control the rate of oxidative phosphorylation, (2) to induce the mitochondrial permeability transition (MPT) and perhaps apoptotic cell death, and (3) to modify the shape of cytosolic Ca 2+ pulses or transients. There is strong evidence that intramitochondrial Ca 2+ controls both the rate of ATP production by oxidative phosphorylation and induction of the MPT. Since the results of these processes are so divergent, the signals inducing them must not be ambiguous. Furthermore, as pointed out by Balaban [J. Mol. Cell. Cardiol. 34 (2002 ) 11259–11271], for any repetitive physiological process dependent on intramitochondrial free Ca 2+ concentration ([Ca 2+ ] m ), a kind of intramitochondrial homeostasis must exist so that Ca 2+ influx during the pulse is matched by Ca 2+ efflux during the period between pulses to avoid either Ca 2+ buildup or depletion. In addition, mitochondrial Ca 2+ transport modifies both spatial and temporal aspects of cytosolic Ca 2+ signaling. Here, we look at the amounts of Ca 2+ necessary to mediate the functions of mitochondrial Ca 2+ transport and at the mechanisms of transport themselves in order to set up a hypothesis about how the mechanisms carry out their roles. The emphasis here is on isolated mitochondria and on general mitochondrial properties in order to focus on how mitochondria alone may function to fulfill their physiological roles even though the interactions of mitochondria with other organelles, particularly with endoplasmic and sarcoplasmic reticulum [Sci. STKE re1 (2004) 1–9], may also influence this story.