Mitochondrial cation transport: a progress report
K. D. Garlid (1994) Mitochondrial cation transport:
A progress report. J. Bioenerget. Biomembr. 26, 537-542.
This report summarizes recent work in our laboratory aimed at understanding
protein-mediated mitochondrial cation transport. We are studying three distinct
cation cycles that contain porters catalyzing influx and efflux of cations
between cytosol and mitochondrial matrix. Each of these cation cycles plays
a major physiological role in the overall energy economy. The K+ cycle maintains
the integrity of the vesicular structure and includes the K+/H+ antiporter,
the KATP channel, and K+ leak driven by the high membrane potential. The Ca2+
cycle relays the signals calling for modulation of ATP production and includes
the Ca2+ channel, the Na+/Ca2+ antiporter, and the Na+/H+ antiporter. The
H+ cycle of brown adipose tissue mitochondria provides heat to hibernating
and newborn mammals and consists of the uncoupling protein, which catalyzes
regulated H+ influx.