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2qvk
From Proteopedia
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==The second Ca2+-binding domain of the Na+-Ca2+ exchanger is essential for regulation: crystal structures and mutational analysis== | ==The second Ca2+-binding domain of the Na+-Ca2+ exchanger is essential for regulation: crystal structures and mutational analysis== | ||
| - | <StructureSection load='2qvk' size='340' side='right' caption='[[2qvk]], [[Resolution|resolution]] 1.45Å' scene=''> | + | <StructureSection load='2qvk' size='340' side='right'caption='[[2qvk]], [[Resolution|resolution]] 1.45Å' scene=''> |
== Structural highlights == | == Structural highlights == | ||
| - | <table><tr><td colspan='2'>[[2qvk]] is a 1 chain structure with sequence from [ | + | <table><tr><td colspan='2'>[[2qvk]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Canis_lupus_familiaris Canis lupus familiaris]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2QVK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2QVK FirstGlance]. <br> |
| - | </td></tr><tr id=' | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.451Å</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=2qvk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2qvk OCA], [https://pdbe.org/2qvk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2qvk RCSB], [https://www.ebi.ac.uk/pdbsum/2qvk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2qvk ProSAT]</span></td></tr> | |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[ | + | |
</table> | </table> | ||
== Function == | == Function == | ||
| - | [ | + | [https://www.uniprot.org/uniprot/NAC1_CANLF NAC1_CANLF] Mediates the exchange of one Ca(2+) ion against three to four Na(+) ions across the cell membrane, and thereby contributes to the regulation of cytoplasmic Ca(2+) levels and Ca(2+)-dependent cellular processes (PubMed:1700476, PubMed:1785844, PubMed:9486131, PubMed:17962412). Contributes to Ca(2+) transport during excitation-contraction coupling in muscle. In a first phase, voltage-gated channels mediate the rapid increase of cytoplasmic Ca(2+) levels due to release of Ca(2+) stores from the endoplasmic reticulum. SLC8A1 mediates the export of Ca(2+) from the cell during the next phase, so that cytoplasmic Ca(2+) levels rapidly return to baseline. Required for normal embryonic heart development and the onset of heart contractions (By similarity).[UniProtKB:P70414]<ref>PMID:1700476</ref> <ref>PMID:1785844</ref> <ref>PMID:17962412</ref> <ref>PMID:19332552</ref> <ref>PMID:9486131</ref> |
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
Check<jmol> | Check<jmol> | ||
<jmolCheckbox> | <jmolCheckbox> | ||
| - | <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/qv/2qvk_consurf.spt"</scriptWhenChecked> | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/qv/2qvk_consurf.spt"</scriptWhenChecked> |
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | ||
<text>to colour the structure by Evolutionary Conservation</text> | <text>to colour the structure by Evolutionary Conservation</text> | ||
</jmolCheckbox> | </jmolCheckbox> | ||
| - | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/ | + | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2qvk ConSurf]. |
<div style="clear:both"></div> | <div style="clear:both"></div> | ||
| - | <div style="background-color:#fffaf0;"> | ||
| - | == Publication Abstract from PubMed == | ||
| - | The Na(+)-Ca(2+) exchanger plays a central role in cardiac contractility by maintaining Ca(2+) homeostasis. Two Ca(2+)-binding domains, CBD1 and CBD2, located in a large intracellular loop, regulate activity of the exchanger. Ca(2+) binding to these regulatory domains activates the transport of Ca(2+) across the plasma membrane. Previously, we solved the structure of CBD1, revealing four Ca(2+) ions arranged in a tight planar cluster. Here, we present structures of CBD2 in the Ca(2+)-bound (1.7-A resolution) and -free (1.4-A resolution) conformations. Like CBD1, CBD2 has a classical Ig fold but coordinates only two Ca(2+) ions in primary and secondary Ca(2+) sites. In the absence of Ca(2+), Lys(585) stabilizes the structure by coordinating two acidic residues (Asp(552) and Glu(648)), one from each of the Ca(2+)-binding sites, and prevents a substantial protein unfolding. We have mutated all of the acidic residues that coordinate the Ca(2+) ions and have examined the effects of these mutations on regulation of exchange activity. Three mutations (E516L, D578V, and E648L) at the primary Ca(2+) site completely remove Ca(2+) regulation, placing the exchanger into a constitutively active state. These are the first data defining the role of CBD2 as a regulatory domain in the Na(+)-Ca(2+) exchanger. | ||
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| - | The second Ca2+-binding domain of the Na+ Ca2+ exchanger is essential for regulation: crystal structures and mutational analysis.,Besserer GM, Ottolia M, Nicoll DA, Chaptal V, Cascio D, Philipson KD, Abramson J Proc Natl Acad Sci U S A. 2007 Nov 20;104(47):18467-72. Epub 2007 Oct 25. PMID:17962412<ref>PMID:17962412</ref> | ||
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| - | </div> | ||
| - | <div class="pdbe-citations 2qvk" style="background-color:#fffaf0;"></div> | ||
== References == | == References == | ||
<references/> | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
| - | [[Category: | + | [[Category: Canis lupus familiaris]] |
| - | [[Category: | + | [[Category: Large Structures]] |
| - | [[Category: | + | [[Category: Abramson J]] |
| - | [[Category: Cascio | + | [[Category: Cascio D]] |
| - | [[Category: Chaptal | + | [[Category: Chaptal V]] |
| - | [[Category: | + | [[Category: Mercado Besserer G]] |
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Current revision
The second Ca2+-binding domain of the Na+-Ca2+ exchanger is essential for regulation: crystal structures and mutational analysis
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