View source for 2kgb


==NMR solution of the regulatory domain cardiac F77W-Troponin C in complex with the cardiac Troponin I 144-163 switch peptide==
<StructureSection load='2kgb' size='340' side='right'caption='[[2kgb]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2kgb]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Human Human]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2KGB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2KGB FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1ap4|1ap4]]</div></td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">TNNC1, TNNC ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</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=2kgb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2kgb OCA], [https://pdbe.org/2kgb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2kgb RCSB], [https://www.ebi.ac.uk/pdbsum/2kgb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2kgb ProSAT]</span></td></tr>
</table>
== Disease ==
[[https://www.uniprot.org/uniprot/TNNC1_HUMAN TNNC1_HUMAN]] Defects in TNNC1 are the cause of cardiomyopathy dilated type 1Z (CMD1Z) [MIM:[https://omim.org/entry/611879 611879]]. Dilated cardiomyopathy is a disorder characterized by ventricular dilation and impaired systolic function, resulting in congestive heart failure and arrhythmia. Patients are at risk of premature death.<ref>PMID:15542288</ref>   Defects in TNNC1 are the cause of familial hypertrophic cardiomyopathy type 13 (CMH13) [MIM:[https://omim.org/entry/613243 613243]]. A hereditary heart disorder characterized by ventricular hypertrophy, which is usually asymmetric and often involves the interventricular septum. The symptoms include dyspnea, syncope, collapse, palpitations, and chest pain. They can be readily provoked by exercise. The disorder has inter- and intrafamilial variability ranging from benign to malignant forms with high risk of cardiac failure and sudden cardiac death.<ref>PMID:11385718</ref> <ref>PMID:16302972</ref> <ref>PMID:18572189</ref> <ref>PMID:19439414</ref>  [[https://www.uniprot.org/uniprot/TNNI3_HUMAN TNNI3_HUMAN]] Defects in TNNI3 are the cause of familial hypertrophic cardiomyopathy type 7 (CMH7) [MIM:[https://omim.org/entry/613690 613690]]. Familial hypertrophic cardiomyopathy is a hereditary heart disorder characterized by ventricular hypertrophy, which is usually asymmetric and often involves the interventricular septum. The symptoms include dyspnea, syncope, collapse, palpitations, and chest pain. They can be readily provoked by exercise. The disorder has inter- and intrafamilial variability ranging from benign to malignant forms with high risk of cardiac failure and sudden cardiac death.<ref>PMID:9241277</ref> <ref>PMID:11815426</ref> <ref>PMID:12707239</ref> <ref>PMID:12974739</ref> <ref>PMID:16199542</ref>   Defects in TNNI3 are the cause of familial restrictive cardiomyopathy type 1 (RCM1) [MIM:[https://omim.org/entry/115210 115210]]. RCM1 is a heart muscle disorder characterized by impaired filling of the ventricles with reduced diastolic volume, in the presence of normal or near normal wall thickness and systolic function.<ref>PMID:12531876</ref>   Defects in TNNI3 are the cause of cardiomyopathy dilated type 2A (CMD2A) [MIM:[https://omim.org/entry/611880 611880]]. Dilated cardiomyopathy is a disorder characterized by ventricular dilation and impaired systolic function, resulting in congestive heart failure and arrhythmia. Patients are at risk of premature death.<ref>PMID:15070570</ref>   Defects in TNNI3 are the cause of cardiomyopathy dilated type 1FF (CMD1FF) [MIM:[https://omim.org/entry/613286 613286]]. Dilated cardiomyopathy is a disorder characterized by ventricular dilation and impaired systolic function, resulting in congestive heart failure and arrhythmia. Patients are at risk of premature death. 
== Function ==
[[https://www.uniprot.org/uniprot/TNNC1_HUMAN TNNC1_HUMAN]] Troponin is the central regulatory protein of striated muscle contraction. Tn consists of three components: Tn-I which is the inhibitor of actomyosin ATPase, Tn-T which contains the binding site for tropomyosin and Tn-C. The binding of calcium to Tn-C abolishes the inhibitory action of Tn on actin filaments. [[https://www.uniprot.org/uniprot/TNNI3_HUMAN TNNI3_HUMAN]] Troponin I is the inhibitory subunit of troponin, the thin filament regulatory complex which confers calcium-sensitivity to striated muscle actomyosin ATPase activity. 
== 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/kg/2kgb_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/main_output.php?pdb_ID=2kgb ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
The unique biophysical properties of tryptophan residues have been exploited for decades to monitor protein structure and dynamics using a variety of spectroscopic techniques, such as fluorescence and nuclear magnetic resonance (NMR). We recently designed a tryptophan mutant in the regulatory N-domain of cardiac troponin C (F77W-cNTnC) to study the domain orientation of troponin C in muscle fibers using solid-state NMR. In our previous study, we determined the NMR structure of calcium-saturated mutant F77W-V82A-cNTnC in the presence of 19% 2,2,2-trifluoroethanol (TFE). TFE is a widely used cosolvent in the biophysical characterization of the solution structures of peptides and proteins. It is generally assumed that the structures are unchanged in the presence of cosolvents at relatively low concentrations, and this has been verified for TFE at the level of the overall secondary and tertiary structure for several calcium regulatory proteins. Here, we present the NMR solution structure of the calcium saturated F77W-cNTnC in presence of its biological binding partner troponin I peptide (cTnI(144-163)) and in the absence of TFE. We have also characterized a panel of six F77W-cNTnC structures in the presence and absence TFE, cTnI(144-163), and the extra mutation V82A, and used (19)F NMR to characterize the effect of TFE on the F77(5fW) analog. Our results show that although TFE did not perturb the overall protein structure, TFE did induce a change in the orientation of the indole ring of the buried tryptophan side chain from the anticipated position based upon homology with other proteins, highlighting the potential dangers of the use of cosolvents.

The effect of the cosolvent trifluoroethanol on a tryptophan side chain orientation in the hydrophobic core of troponin C.,Julien O, Mercier P, Crane ML, Sykes BD Protein Sci. 2009 Jun;18(6):1165-74. PMID:19472326<ref>PMID:19472326</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 2kgb" style="background-color:#fffaf0;"></div>

==See Also==
*[[Troponin|Troponin]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Human]]
[[Category: Large Structures]]
[[Category: Crane, M L]]
[[Category: Julien, O]]
[[Category: Mercier, P]]
[[Category: Sykes, B D]]
[[Category: Acetylation]]
[[Category: Actin-binding]]
[[Category: Calcium]]
[[Category: Cardiomyopathy]]
[[Category: Cntnc]]
[[Category: Contractile protein-ca binding protein complex]]
[[Category: Disease mutation]]
[[Category: Muscle protein]]
[[Category: Phosphoprotein]]
[[Category: Polymorphism]]
[[Category: Switch peptide]]
[[Category: Tfe]]
[[Category: Tni144-163]]
[[Category: Troponin c]]
[[Category: Troponin i]]