View source for 5swk


==Crystal structure of p53 epitope-scaffold based on a inhibitor of cysteine proteases in complex with human MDM2==
<StructureSection load='5swk' size='340' side='right'caption='[[5swk]], [[Resolution|resolution]] 1.92&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5swk]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Entamoeba_histolytica Entamoeba histolytica] and [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5SWK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5SWK 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]] 1.923&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=5swk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5swk OCA], [https://pdbe.org/5swk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5swk RCSB], [https://www.ebi.ac.uk/pdbsum/5swk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5swk ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/MDM2_HUMAN MDM2_HUMAN] Note=Seems to be amplified in certain tumors (including soft tissue sarcomas, osteosarcomas and gliomas). A higher frequency of splice variants lacking p53 binding domain sequences was found in late-stage and high-grade ovarian and bladder carcinomas. Four of the splice variants show loss of p53 binding.
== Function ==
[https://www.uniprot.org/uniprot/MDM2_HUMAN MDM2_HUMAN] E3 ubiquitin-protein ligase that mediates ubiquitination of p53/TP53, leading to its degradation by the proteasome. Inhibits p53/TP53- and p73/TP73-mediated cell cycle arrest and apoptosis by binding its transcriptional activation domain. Also acts as an ubiquitin ligase E3 toward itself and ARRB1. Permits the nuclear export of p53/TP53. Promotes proteasome-dependent ubiquitin-independent degradation of retinoblastoma RB1 protein. Inhibits DAXX-mediated apoptosis by inducing its ubiquitination and degradation. Component of the TRIM28/KAP1-MDM2-p53/TP53 complex involved in stabilizing p53/TP53. Also component of the TRIM28/KAP1-ERBB4-MDM2 complex which links growth factor and DNA damage response pathways. Mediates ubiquitination and subsequent proteasome degradation of DYRK2 in nucleus. Ubiquitinates IGF1R and promotes it to proteasomal degradation.<ref>PMID:12821780</ref> <ref>PMID:15053880</ref> <ref>PMID:15195100</ref> <ref>PMID:16337594</ref> <ref>PMID:15632057</ref> <ref>PMID:17290220</ref> <ref>PMID:19098711</ref> <ref>PMID:19219073</ref> <ref>PMID:19965871</ref> <ref>PMID:20858735</ref> <ref>PMID:20173098</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Antibodies recognize protein targets with great affinity and specificity. However, posttranslational modifications and the presence of intrinsic disulfide-bonds pose difficulties for their industrial use. The immunoglobulin fold is one of the most ubiquitous folds in nature and it is found in many proteins besides antibodies. An example of a protein family with an immunoglobulin-like fold is the Cysteine Protease Inhibitors (ICP) family I42 of the MEROPs database for protease and protease inhibitors. Members of this protein family are thermostable and do not present internal disulfide bonds. Crystal structures of several ICPs indicate that they resemble the Ig-like domain of the human T cell co-receptor CD8alpha As ICPs present 2 flexible recognition loops that vary accordingly to their targeted protease, we hypothesize that members of this protein family would be ideal to design peptide aptamers that mimic protein-protein interactions. Herein, we use an ICP variant from Entamoeba histolytica (EhICP1) to mimic the interaction between p53 and MDM2. We found that a 13 amino-acid peptide derived from p53 can be introduced in 2 variable loops (DE, FG) but not the third (BC). Chimeric EhICP1-p53 form a stable complex with MDM2 at a micromolar range. Crystal structure of the EhICP1-p53(FG)-loop variant in complex with MDM2 reveals a swapping subdomain between 2 chimeric molecules, however, the p53 peptide interacts with MDM2 as in previous crystal structures. The structural details of the EhICP1-p53(FG) interaction with MDM2 resemble the interaction between an antibody and MDM2.

Mimicking a p53-MDM2 interaction based on a stable immunoglobulin-like domain scaffold.,Jimenez-Sandoval P, Madrigal-Carrillo EA, Santamaria-Suarez HA, Maturana D, Renteria-Gonzalez I, Benitez-Cardoza CG, Torres-Larios A, Brieba LG Proteins. 2018 Jul;86(7):802-812. doi: 10.1002/prot.25519. Epub 2018 May 6. PMID:29696695<ref>PMID:29696695</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5swk" style="background-color:#fffaf0;"></div>

==See Also==
*[[MDM2 3D structures|MDM2 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Entamoeba histolytica]]
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Brieba LG]]
[[Category: Jimenez-Sandoval P]]