2vaf
From Proteopedia
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| - | + | ==CRYSTAL STRUCTURE OF HUMAN CARDIAC CALSEQUESTRIN== | |
| - | === | + | <StructureSection load='2vaf' size='340' side='right' caption='[[2vaf]], [[Resolution|resolution]] 3.80Å' scene=''> |
| - | + | == Structural highlights == | |
| + | <table><tr><td colspan='2'>[[2vaf]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=2v0q 2v0q]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2VAF OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2VAF FirstGlance]. <br> | ||
| + | </td></tr><tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2vaf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2vaf OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2vaf RCSB], [http://www.ebi.ac.uk/pdbsum/2vaf PDBsum]</span></td></tr> | ||
| + | <table> | ||
| + | == Disease == | ||
| + | [[http://www.uniprot.org/uniprot/CASQ2_HUMAN CASQ2_HUMAN]] Defects in CASQ2 are the cause of catecholaminergic polymorphic ventricular tachycardia type 2 (CPVT2) [MIM:[http://omim.org/entry/611938 611938]]; also known as stress-induced polymorphic ventricular tachycardia (VTSIP). CPVT2 is an autosomal recessive form of arrhythmogenic disorder characterized by stress-induced, bidirectional ventricular tachycardia that may degenerate into cardiac arrest and cause sudden death.<ref>PMID:17881003</ref> <ref>PMID:11704930</ref> <ref>PMID:15485681</ref> <ref>PMID:16908766</ref> <ref>PMID:18399795</ref> | ||
| + | == Function == | ||
| + | [[http://www.uniprot.org/uniprot/CASQ2_HUMAN CASQ2_HUMAN]] Calsequestrin is a high-capacity, moderate affinity, calcium-binding protein and thus acts as an internal calcium store in muscle. The release of calcium bound to calsequestrin through a calcium release channel triggers muscle contraction. The skeletal muscle isoform (CASQ1) binds around 80 Ca(2+) ions, while the cardiac isoform (CASQ2) binds approximately 60 Ca(2+) ions.<ref>PMID:17881003</ref> | ||
| + | == Evolutionary Conservation == | ||
| + | [[Image:Consurf_key_small.gif|200px|right]] | ||
| + | Check<jmol> | ||
| + | <jmolCheckbox> | ||
| + | <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/va/2vaf_consurf.spt"</scriptWhenChecked> | ||
| + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | ||
| + | <text>to colour the structure by Evolutionary Conservation</text> | ||
| + | </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/chain_selection.php?pdb_ID=2ata ConSurf]. | ||
| + | <div style="clear:both"></div> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Mutations of conserved residues of human cardiac calsequestrin (hCSQ2), a high-capacity, low-affinity Ca2+-binding protein in the sarcoplasmic reticulum, have been associated with catecholamine-induced polymorphic ventricular tachycardia (CPVT). In order to understand the molecular mechanism and pathophysiological link between these CPVT-related missense mutations of hCSQ2 and the resulting arrhythmias, we generated three CPVT-causing mutants of hCSQ2 (R33Q, L167H, and D307H) and two non-pathological mutants (T66A and V76M) and investigated the effect of these mutations. In addition, we determined the crystal structure of the corresponding wild-type hCSQ2 to gain insight into the structural effects of those mutations. Our data show clearly that all three CPVT-related mutations lead to significant reduction in Ca2+-binding capacity in spite of the similarity of their secondary structures to that of the wild-type hCSQ2. Light-scattering experiments indicate that the Ca2+-dependent monomer-polymer transitions of the mutants are quite different, confirming that the linear polymerization behavior of CSQ is linked directly to its high-capacity Ca2+ binding. R33Q and D307H mutations result in a monomer that appears to be unable to form a properly oriented dimer. On the other hand, the L167H mutant has a disrupted hydrophobic core in domain II, resulting in high molecular aggregates, which cannot respond to Ca2+. Although one of the non-pathological mutants, T66A, shares characteristics with the wild-type, the other null mutant, V76M, shows significantly altered Ca2+-binding and polymerization behaviors, calling for careful reconsideration of its status. | ||
| - | + | Characterization of human cardiac calsequestrin and its deleterious mutants.,Kim E, Youn B, Kemper L, Campbell C, Milting H, Varsanyi M, Kang C J Mol Biol. 2007 Nov 2;373(4):1047-57. Epub 2007 Aug 29. PMID:17881003<ref>PMID:17881003</ref> | |
| - | + | ||
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | == References == | |
| - | == | + | <references/> |
| - | + | __TOC__ | |
| - | + | </StructureSection> | |
| - | + | ||
| - | + | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Campbell, C.]] | [[Category: Campbell, C.]] | ||
Revision as of 01:32, 1 October 2014
CRYSTAL STRUCTURE OF HUMAN CARDIAC CALSEQUESTRIN
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