View source for 2axi


==HDM2 in complex with a beta-hairpin==
<StructureSection load='2axi' size='340' side='right'caption='[[2axi]], [[Resolution|resolution]] 1.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2axi]] is a 2 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=2AXI OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2AXI 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]] 1.4&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=6CW:6-CHLORO-L-TRYPTOPHAN'>6CW</scene>, <scene name='pdbligand=DPR:D-PROLINE'>DPR</scene>, <scene name='pdbligand=MPO:3[N-MORPHOLINO]PROPANE+SULFONIC+ACID'>MPO</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=2axi FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2axi OCA], [https://pdbe.org/2axi PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2axi RCSB], [https://www.ebi.ac.uk/pdbsum/2axi PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2axi 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> 
== 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/ax/2axi_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.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=2axi ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Inhibitors of the interaction between the p53 tumor-suppressor protein and its natural human inhibitor HDM2 are attractive as potential anticancer agents. In earlier work we explored designing beta-hairpin peptidomimetics of the alpha-helical epitope on p53 that would bind tightly to the p53-binding site on HDM2. The beta-hairpin is used as a scaffold to display energetically hot residues in an optimal array for interaction with HDM2. The initial lead beta-hairpin mimetic, with a weak inhibitory activity (IC(50)=125 microM), was optimized to afford cyclo-(L-Pro-Phe-Glu-6ClTrp-Leu-Asp-Trp-Glu-Phe-D-Pro) (where 6ClTrp=L-6-chlorotryptophan), which has an affinity almost 1,000 times higher (IC(50)=140 nM). In this work, insights into the origins of this affinity maturation based on structure-activity studies and an X-ray crystal structure of the inhibitor/HDM2(residues 17-125) complex at 1.4 A resolution are described. The crystal structure confirms the beta-hairpin conformation of the bound ligand, and also reveals that a significant component of the affinity increase arises through new aromatic/aromatic stacking interactions between side chains around the hairpin and groups on the surface of HDM2.

Structure-activity studies in a family of beta-hairpin protein epitope mimetic inhibitors of the p53-HDM2 protein-protein interaction.,Fasan R, Dias RL, Moehle K, Zerbe O, Obrecht D, Mittl PR, Grutter MG, Robinson JA Chembiochem. 2006 Mar;7(3):515-26. PMID:16511824<ref>PMID:16511824</ref>

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

==See Also==
*[[MDM2 3D structures|MDM2 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Fasan R]]
[[Category: Gruetter MG]]
[[Category: Mittl PRE]]
[[Category: Robinson J]]