On the function of pentameric phospholamban: ion channel or storage form?
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ABSTRACT:
SUBMITTER: Becucci L
PROVIDER: S-EPMC2712152 | biostudies-literature | 2009 May
REPOSITORIES: biostudies-literature
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On the function of pentameric phospholamban: ion channel or storage form?
Becucci Lucia L Cembran Alessandro A Karim Christine B CB Thomas David D DD Guidelli Rolando R Gao Jiali J Veglia Gianluigi G
Biophysical journal 20090501 10
Phospholamban (PLN) is an integral membrane protein that inhibits the sarcoplasmic reticulum Ca(2+)-ATPase, thereby regulating muscle contractility. We report a combined electrochemical and theoretical study demonstrating that the pentameric PLN does not possess channel activity for conducting chloride or calcium ions across the lipid membrane. This suggests that the pentameric configuration of PLN primarily serves as a storage form for the regulatory function of muscle relaxation by the PLN mon ...[more]
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