Ca2+ regulation of ion transport in the Na+/Ca2+ exchanger.
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ABSTRACT:
SUBMITTER: Hilge M
PROVIDER: S-EPMC3442498 | biostudies-literature | 2012 Sep
REPOSITORIES: biostudies-literature
Publications
Ca2+ regulation of ion transport in the Na+/Ca2+ exchanger.
The Journal of biological chemistry 20120720 38
The binding of Ca(2+) to two adjacent Ca(2+)-binding domains, CBD1 and CBD2, regulates ion transport in the Na(+)/Ca(2+) exchanger. As sensors for intracellular Ca(2+), the CBDs form electrostatic switches that induce the conformational changes required to initiate and sustain Na(+)/Ca(2+) exchange. Depending on the presence of a few key residues in the Ca(2+)-binding sites, zero to four Ca(2+) ions can bind with affinities between 0.1 to 20 μm. Importantly, variability in CBD2 as a consequence ...[more]
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