Ryanodine Receptor Open Times Are Determined in the Closed State.
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ABSTRACT:
SUBMITTER: Fill M
PROVIDER: S-EPMC6170654 | biostudies-literature | 2018 Oct
REPOSITORIES: biostudies-literature
Publications
Ryanodine Receptor Open Times Are Determined in the Closed State.
Fill Michael M Gillespie Dirk D
Biophysical journal 20180913 7
The ryanodine receptor (RyR) ion channel releases Ca<sup>2+</sup> from intracellular stores by conducting Ca<sup>2+</sup> but also by recruiting neighboring RyRs to open, as RyRs are activated by micromolar levels of cytosolic Ca<sup>2+</sup>. Using long single-RyR recordings of the cardiac isoform (RyR2), we conclude that Ca<sup>2+</sup> binding to the cytosolic face of RyR while the channel is closed determines the distribution of open times. This mechanism explains previous findings that RyR ...[more]
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