2fws
From Proteopedia
(New page: 200px<br /><applet load="2fws" size="450" color="white" frame="true" align="right" spinBox="true" caption="2fws" /> '''First Ca2+ binding domain of the Na,Ca-excha...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:2fws.gif|left|200px]]<br /><applet load="2fws" size=" | + | [[Image:2fws.gif|left|200px]]<br /><applet load="2fws" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2fws" /> | caption="2fws" /> | ||
'''First Ca2+ binding domain of the Na,Ca-exchanger (NCX1)'''<br /> | '''First Ca2+ binding domain of the Na,Ca-exchanger (NCX1)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The plasma membrane Na+/Ca2+ exchanger (NCX) is almost certainly the major | + | The plasma membrane Na+/Ca2+ exchanger (NCX) is almost certainly the major Ca2+ extrusion mechanism in cardiac myocytes. Binding of Na+ and Ca2+ ions to its large cytosolic loop regulates ion transport of the exchanger. We determined the solution structures of two Ca2+ binding domains (CBD1 and CBD2) that, together with an alpha-catenin-like domain (CLD), form the regulatory exchanger loop. CBD1 and CBD2 are very similar in the Ca2+ bound state and describe the Calx-beta motif. Strikingly, in the absence of Ca2+, the upper half of CBD1 unfolds while CBD2 maintains its structural integrity. Together with a 7-fold higher affinity for Ca2+, this suggests that CBD1 is the primary Ca2+ sensor. Specific point mutations in either domain largely allow the interchange of their functionality and uncover the mechanism underlying Ca2+ sensing in NCX. |
==About this Structure== | ==About this Structure== | ||
| - | 2FWS is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Canis_lupus_familiaris Canis lupus familiaris] with CA as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 2FWS is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Canis_lupus_familiaris Canis lupus familiaris] with <scene name='pdbligand=CA:'>CA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FWS OCA]. |
==Reference== | ==Reference== | ||
| Line 15: | Line 15: | ||
[[Category: Aelen, J.]] | [[Category: Aelen, J.]] | ||
[[Category: Hilge, M.]] | [[Category: Hilge, M.]] | ||
| - | [[Category: Vuister, G | + | [[Category: Vuister, G W.]] |
[[Category: CA]] | [[Category: CA]] | ||
[[Category: beta-bulge]] | [[Category: beta-bulge]] | ||
| Line 23: | Line 23: | ||
[[Category: greek key]] | [[Category: greek key]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:25:55 2008'' |
Revision as of 15:25, 21 February 2008
|
First Ca2+ binding domain of the Na,Ca-exchanger (NCX1)
Overview
The plasma membrane Na+/Ca2+ exchanger (NCX) is almost certainly the major Ca2+ extrusion mechanism in cardiac myocytes. Binding of Na+ and Ca2+ ions to its large cytosolic loop regulates ion transport of the exchanger. We determined the solution structures of two Ca2+ binding domains (CBD1 and CBD2) that, together with an alpha-catenin-like domain (CLD), form the regulatory exchanger loop. CBD1 and CBD2 are very similar in the Ca2+ bound state and describe the Calx-beta motif. Strikingly, in the absence of Ca2+, the upper half of CBD1 unfolds while CBD2 maintains its structural integrity. Together with a 7-fold higher affinity for Ca2+, this suggests that CBD1 is the primary Ca2+ sensor. Specific point mutations in either domain largely allow the interchange of their functionality and uncover the mechanism underlying Ca2+ sensing in NCX.
About this Structure
2FWS is a Single protein structure of sequence from Canis lupus familiaris with as ligand. Full crystallographic information is available from OCA.
Reference
Ca2+ regulation in the Na+/Ca2+ exchanger involves two markedly different Ca2+ sensors., Hilge M, Aelen J, Vuister GW, Mol Cell. 2006 Apr 7;22(1):15-25. PMID:16600866
Page seeded by OCA on Thu Feb 21 17:25:55 2008
