View source for 2qlb


==Crystal Structure of caspase-7 with inhibitor AC-ESMD-CHO==
<StructureSection load='2qlb' size='340' side='right'caption='[[2qlb]], [[Resolution|resolution]] 2.25&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2qlb]] is a 7 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2QLB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2QLB FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.25&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ACE:ACETYL+GROUP'>ACE</scene>, <scene name='pdbligand=ASJ:(3S)-3-AMINO-4-HYDROXYBUTANOIC+ACID'>ASJ</scene>, <scene name='pdbligand=CIT:CITRIC+ACID'>CIT</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=2qlb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2qlb OCA], [https://pdbe.org/2qlb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2qlb RCSB], [https://www.ebi.ac.uk/pdbsum/2qlb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2qlb ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CASP7_HUMAN CASP7_HUMAN] Involved in the activation cascade of caspases responsible for apoptosis execution. Cleaves and activates sterol regulatory element binding proteins (SREBPs). Proteolytically cleaves poly(ADP-ribose) polymerase (PARP) at a '216-Asp-|-Gly-217' bond. Overexpression promotes programmed cell death.
== 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/2qlb_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=2qlb ConSurf].
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== Publication Abstract from PubMed ==
Many protein substrates of caspases are cleaved at noncanonical sites in comparison to the recognition motifs reported for the three caspase subgroups. To provide insight into the specificity and aid in the design of drugs to control cell death, crystal structures of caspase-7 were determined in complexes with six peptide analogs (Ac-DMQD-Cho, Ac-DQMD-Cho, Ac-DNLD-Cho, Ac-IEPD-Cho, Ac-ESMD-Cho, Ac-WEHD-Cho) that span the major recognition motifs of the three subgroups. The crystal structures show that the S2 pocket of caspase-7 can accommodate diverse residues. Glu is not required at the P3 position because Ac-DMQD-Cho, Ac-DQMD-Cho and Ac-DNLD-Cho with varied P3 residues are almost as potent as the canonical Ac-DEVD-Cho. P4 Asp was present in the better inhibitors of caspase-7. However, the S4 pocket of executioner caspase-7 has alternate regions for binding of small branched aliphatic or polar residues similar to those of initiator caspase-8. The observed plasticity of the caspase subsites agrees very well with the reported cleavage of many proteins at noncanonical sites. The results imply that factors other than the P4-P1 sequence, such as exosites, contribute to the in vivo substrate specificity of caspases. The novel peptide binding site identified on the molecular surface of the current structures is suggested to be an exosite of caspase-7. These results should be considered in the design of selective small molecule inhibitors of this pharmacologically important protease.

Plasticity of S2-S4 specificity pockets of executioner caspase-7 revealed by structural and kinetic analysis.,Agniswamy J, Fang B, Weber IT FEBS J. 2007 Sep;274(18):4752-65. Epub 2007 Aug 14. PMID:17697120<ref>PMID:17697120</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 2qlb" style="background-color:#fffaf0;"></div>

==See Also==
*[[Caspase 3D structures|Caspase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Agniswamy J]]
[[Category: Fang B]]
[[Category: Weber I]]