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| | ==Cryo-EM structure of the magnesium channel CorA in the closed symmetric magnesium-bound state== | | ==Cryo-EM structure of the magnesium channel CorA in the closed symmetric magnesium-bound state== |
| - | <StructureSection load='3jcf' size='340' side='right' caption='[[3jcf]], [[Resolution|resolution]] 3.80Å' scene=''> | + | <SX load='3jcf' size='340' side='right' viewer='molstar' caption='[[3jcf]], [[Resolution|resolution]] 3.80Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[3jcf]] is a 5 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_43589 Atcc 43589]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3JCF OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3JCF FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[3jcf]] is a 5 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermotoga_maritima Thermotoga maritima]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3JCF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3JCF FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.8Å</td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3jcg|3jcg]]</td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">corA, TM_0561 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=2336 ATCC 43589])</td></tr>
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=3jcf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3jcf OCA], [https://pdbe.org/3jcf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3jcf RCSB], [https://www.ebi.ac.uk/pdbsum/3jcf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3jcf ProSAT]</span></td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3jcf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3jcf OCA], [http://pdbe.org/3jcf PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3jcf RCSB], [http://www.ebi.ac.uk/pdbsum/3jcf PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3jcf ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/CORA_THEMA CORA_THEMA]] Mediates influx of magnesium ions (By similarity). | + | [https://www.uniprot.org/uniprot/CORA_THEMA CORA_THEMA] Mediates influx of magnesium ions (By similarity). |
| - | <div style="background-color:#fffaf0;">
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| - | == Publication Abstract from PubMed ==
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| - | CorA, the major Mg(2+) uptake system in prokaryotes, is gated by intracellular Mg(2+) (KD approximately 1-2 mM). X-ray crystallographic studies of CorA show similar conformations under Mg(2+)-bound and Mg(2+)-free conditions, but EPR spectroscopic studies reveal large Mg(2+)-driven quaternary conformational changes. Here, we determined cryo-EM structures of CorA in the Mg(2+)-bound closed conformation and in two open Mg(2+)-free states at resolutions of 3.8, 7.1, and 7.1 A, respectively. In the absence of bound Mg(2+), four of the five subunits are displaced to variable extents ( approximately 10-25 A) by hinge-like motions as large as approximately 35 degrees at the stalk helix. The transition between a single 5-fold symmetric closed state and an ensemble of low Mg(2+), open, asymmetric conformational states is, thus, the key structural signature of CorA gating. This mechanism is likely to apply to other structurally similar divalent ion channels.
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| - | Cryo-EM Structures of the Magnesium Channel CorA Reveal Symmetry Break upon Gating.,Matthies D, Dalmas O, Borgnia MJ, Dominik PK, Merk A, Rao P, Reddy BG, Islam S, Bartesaghi A, Perozo E, Subramaniam S Cell. 2016 Feb 11;164(4):747-56. doi: 10.1016/j.cell.2015.12.055. PMID:26871634<ref>PMID:26871634</ref>
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| - | </div>
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| - | <div class="pdbe-citations 3jcf" style="background-color:#fffaf0;"></div>
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| - | == References ==
| + | |
| - | <references/>
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| | __TOC__ | | __TOC__ |
| - | </StructureSection> | + | </SX> |
| - | [[Category: Atcc 43589]] | + | [[Category: Large Structures]] |
| - | [[Category: Matthies, D]] | + | [[Category: Thermotoga maritima]] |
| - | [[Category: Perozo, E]] | + | [[Category: Matthies D]] |
| - | [[Category: Subramaniam, S]] | + | [[Category: Perozo E]] |
| - | [[Category: Conformational change]] | + | [[Category: Subramaniam S]] |
| - | [[Category: Direct electron detector]]
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| - | [[Category: Gating mechanism]]
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| - | [[Category: Ion channel]]
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| - | [[Category: K2]]
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| - | [[Category: Magnesium channel]]
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| - | [[Category: Membrane protein]]
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| - | [[Category: Pentameric complex]]
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| - | [[Category: Symmetry vs. asymmetry]]
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| - | [[Category: Transport protein]]
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