View source for 1qlk


==SOLUTION STRUCTURE OF CA(2+)-LOADED RAT S100B (BETABETA) NMR, 20 STRUCTURES==
<StructureSection load='1qlk' size='340' side='right'caption='[[1qlk]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1qlk]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QLK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1QLK FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</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='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1qlk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1qlk OCA], [https://pdbe.org/1qlk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1qlk RCSB], [https://www.ebi.ac.uk/pdbsum/1qlk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1qlk ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/S100B_RAT S100B_RAT] Weakly binds calcium but binds zinc very tightly-distinct binding sites with different affinities exist for both ions on each monomer. Physiological concentrations of potassium ion antagonize the binding of both divalent cations, especially affecting high-affinity calcium-binding sites. Binds to and initiates the activation of STK38 by releasing autoinhibitory intramolecular interactions within the kinase. Interaction with AGER after myocardial infarction may play a role in myocyte apoptosis by activating ERK1/2 and p53/TP53 signaling. Could assist ATAD3A cytoplasmic processing, preventing aggregation and favoring mitochondrial localization.<ref>PMID:19910580</ref> <ref>PMID:20351179</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/ql/1qlk_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=1qlk ConSurf].
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== Publication Abstract from PubMed ==
The three-dimensional structure of Ca2+-bound rat S100B(betabeta) has been determined using data from a series of two-dimensional (2D), three-dimensional (3D), and four-dimensional (4D) nuclear magnetic resonance (NMR) experiments. Each S100beta subunit (91 residues) contains four helixes (helix 1, E2-R20; helix 2, K29-N38; helix 3, Q50-D61; and helix 4, F70-A83) and one antiparallel beta-sheet (strand 1, K26-K28; and strand 2, E67-D69) which brings the normal and pseudo EF-hands together. As found previously for rat apo-S100B(betabeta) [Drohat, A. C., et al. (1996) Biochemistry 35, 11577-11588], helixes 1, 1', 4, and 4' associate to form an X-type four-helix bundle at the symmetric dimer interface. Additionally, Ca2+ binding does not significantly change the interhelical angle of helixes 1 and 2 in the pseudo EF-hand (apo, Omega1-2 = 132 +/- 4 degrees; and Ca2+-bound, Omega1-2 = 137 +/- 5 degrees). However, the interhelical angle of helixes 3 and 4 in the normal EF-hand (Omega3-4 = 106 +/- 4 degrees) changed significantly upon the addition of Ca2+ (DeltaOmega3-4 = 112 +/- 5 degrees) and is similar to that of the Ca2+-bound EF-hands in calbindin D9K, calmodulin, and troponin (84 degrees &lt;/= Omega &lt;/= 128 degrees). Further, the four helixes within each S100beta subunit form a splayed-type four-helix bundle (four perpendicular helixes) as observed in Ca2+-bound calbindin D9K. The large Ca2+-dependent conformational change involving helix 3 exposes a cleft, defined by residues in the hinge region, the C-terminal loop, and helix 3, which is absent in the apo structure. This surface on Ca2+-bound S100B(betabeta) is likely important for target protein binding.

Solution structure of calcium-bound rat S100B(betabeta) as determined by nuclear magnetic resonance spectroscopy,.,Drohat AC, Baldisseri DM, Rustandi RR, Weber DJ Biochemistry. 1998 Mar 3;37(9):2729-40. PMID:9485423<ref>PMID:9485423</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[S100 proteins 3D structures|S100 proteins 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Rattus norvegicus]]
[[Category: Baldisseri DM]]
[[Category: Drohat AC]]
[[Category: Rustandi RR]]
[[Category: Weber DJ]]