View source for 5vhf


==Conformational Landscape of the p28-Bound Human Proteasome Regulatory Particle==
<SX load='5vhf' size='340' side='right' viewer='molstar' caption='[[5vhf]], [[Resolution|resolution]] 5.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5vhf]] is a 10 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=5VHF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5VHF FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 5.7&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</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=5vhf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5vhf OCA], [https://pdbe.org/5vhf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5vhf RCSB], [https://www.ebi.ac.uk/pdbsum/5vhf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5vhf ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PSD10_HUMAN PSD10_HUMAN] Acts as a chaperone during the assembly of the 26S proteasome, specifically of the PA700/19S regulatory complex (RC). In the initial step of the base subcomplex assembly is part of an intermediate PSMD10:PSMC4:PSMC5:PAAF1 module which probably assembles with a PSMD5:PSMC2:PSMC1:PSMD2 module. Independently of the proteasome, regulates EGF-induced AKT activation through inhibition of the RHOA/ROCK/PTEN pahway, leading to prolonged AKT activation. Plays an important role in RAS-induced tumorigenesis.<ref>PMID:10613832</ref> <ref>PMID:11900540</ref> <ref>PMID:11779854</ref> <ref>PMID:16023600</ref> <ref>PMID:18040287</ref> <ref>PMID:19490896</ref> <ref>PMID:19729910</ref> <ref>PMID:20628200</ref>   Acts as an proto-oncoprotein by being involved in negative regulation of tumor suppressors RB1 and p53/TP53. Overexpression is leading to phosphorylation of RB1 and proteasomal degradation of RB1. Regulates CDK4-mediated phosphorylation of RB1 by competing with CDKN2A for binding with CDK4. Facilitates binding of MDM2 to p53/TP53 and the mono- and polyubiquitination of p53/TP53 by MDM2 suggesting a function in targeting the TP53:MDM2 complex to the 26S proteasome. Involved in p53-independent apoptosis. Involved in regulation of NF-kappa-B by retaining it in the cytoplasm. Binds to the NF-kappa-B component RELA and accelerates its XPO1/CRM1-mediated nuclear export.<ref>PMID:10613832</ref> <ref>PMID:11900540</ref> <ref>PMID:11779854</ref> <ref>PMID:16023600</ref> <ref>PMID:18040287</ref> <ref>PMID:19490896</ref> <ref>PMID:19729910</ref> <ref>PMID:20628200</ref> 
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== Publication Abstract from PubMed ==
The proteasome holoenzyme is activated by its regulatory particle (RP) consisting of two subcomplexes, the lid and the base. A key event in base assembly is the formation of a heterohexameric ring of AAA-ATPases, which is guided by at least four RP assembly chaperones in mammals: PAAF1, p28/gankyrin, p27/PSMD9, and S5b. Using cryogenic electron microscopy, we analyzed the non-AAA structure of the p28-bound human RP at 4.5 A resolution and determined seven distinct conformations of the Rpn1-p28-AAA subcomplex within the p28-bound RP at subnanometer resolutions. Remarkably, the p28-bound AAA ring does not form a channel in the free RP and spontaneously samples multiple "open" and "closed" topologies at the Rpt2-Rpt6 and Rpt3-Rpt4 interfaces. Our analysis suggests that p28 assists the proteolytic core particle to select a specific conformation of the ATPase ring for RP engagement and is released in a shoehorn-like fashion in the last step of the chaperone-mediated proteasome assembly.

Conformational Landscape of the p28-Bound Human Proteasome Regulatory Particle.,Lu Y, Wu J, Dong Y, Chen S, Sun S, Ma YB, Ouyang Q, Finley D, Kirschner MW, Mao Y Mol Cell. 2017 Jul 20;67(2):322-333.e6. doi: 10.1016/j.molcel.2017.06.007. Epub, 2017 Jul 6. PMID:28689658<ref>PMID:28689658</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 5vhf" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ankyrin 3D structures|Ankyrin 3D structures]]
*[[Proteasome 3D structures|Proteasome 3D structures]]
== References ==
<references/>
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</SX>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Chen S]]
[[Category: Dong Y]]
[[Category: Finley D]]
[[Category: Kirschner MW]]
[[Category: Lu Y]]
[[Category: Ma YB]]
[[Category: Mao Y]]
[[Category: Ouyang Q]]
[[Category: Sun S]]
[[Category: Wu J]]