1zll
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NMR Structure of Unphosphorylated Human Phospholamban Pentamer
OverviewOverview
Contraction and relaxation of heart muscle cells is regulated by cycling, of calcium between cytoplasm and sarcoplasmic reticulum. Human, phospholamban (PLN), expressed in the sarcoplasmic reticulum membrane as a, 30-kDa homopentamer, controls cellular calcium levels by a mechanism that, depends on its phosphorylation. Since PLN was discovered approximately 30, years ago, extensive studies have aimed to explain how it influences, calcium pumps and to determine whether it acts as an ion channel. We have, determined by solution NMR methods the atomic resolution structure of an, unphosphorylated PLN pentamer in dodecylphosphocholine micelles. The, unusual bellflower-like assembly is held together by leucine/isoleucine, zipper motifs along the membrane-spanning helices. The structure reveals a, channel-forming architecture that could allow passage of small ions. The, central pore gradually widens toward the cytoplasmic end as the, transmembrane helices twist around each other and bend outward. The, dynamic N-terminal amphipathic helices point away from the membrane, perhaps facilitating recognition and inhibition of the calcium pump.
DiseaseDisease
Known diseases associated with this structure: Cardiomyopathy, dilated, 1P OMIM:[172405]
About this StructureAbout this Structure
1ZLL is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
ReferenceReference
The structure of phospholamban pentamer reveals a channel-like architecture in membranes., Oxenoid K, Chou JJ, Proc Natl Acad Sci U S A. 2005 Aug 2;102(31):10870-5. Epub 2005 Jul 25. PMID:16043693
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