View source for 6xir


==Cryo-EM Structure of K63 Ubiquitinated Yeast Translocating Ribosome under Oxidative Stress==
<StructureSection load='6xir' size='340' side='right'caption='[[6xir]], [[Resolution|resolution]] 3.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6xir]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6XIR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6XIR 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]] 3.2&#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=6xir FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6xir OCA], [https://pdbe.org/6xir PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6xir RCSB], [https://www.ebi.ac.uk/pdbsum/6xir PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6xir ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RL31A_YEAST RL31A_YEAST] 
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== Publication Abstract from PubMed ==
Subpopulations of ribosomes are responsible for fine tuning the control of protein synthesis in dynamic environments. K63 ubiquitination of ribosomes has emerged as a new posttranslational modification that regulates protein synthesis during cellular response to oxidative stress. K63 ubiquitin, a type of ubiquitin chain that functions independently of the proteasome, modifies several sites at the surface of the ribosome, however, we lack a molecular understanding on how this modification affects ribosome structure and function. Using cryoelectron microscopy (cryo-EM), we resolved the first three-dimensional (3D) structures of K63 ubiquitinated ribosomes from oxidatively stressed yeast cells at 3.5-3.2 A resolution. We found that K63 ubiquitinated ribosomes are also present in a polysome arrangement, similar to that observed in yeast polysomes, which we determined using cryoelectron tomography (cryo-ET). We further showed that K63 ubiquitinated ribosomes are captured uniquely at the rotated pretranslocation stage of translation elongation. In contrast, cryo-EM structures of ribosomes from mutant cells lacking K63 ubiquitin resolved at 4.4-2.7 A showed 80S ribosomes represented in multiple states of translation, suggesting that K63 ubiquitin regulates protein synthesis at a selective stage of elongation. Among the observed structural changes, ubiquitin mediates the destabilization of proteins in the 60S P-stalk and in the 40S beak, two binding regions of the eukaryotic elongation factor eEF2. These changes would impact eEF2 function, thus, inhibiting translocation. Our findings help uncover the molecular effects of K63 ubiquitination on ribosomes, providing a model of translation control during oxidative stress, which supports elongation halt at pretranslocation.

Structural impact of K63 ubiquitin on yeast translocating ribosomes under oxidative stress.,Zhou Y, Kastritis PL, Dougherty SE, Bouvette J, Hsu AL, Burbaum L, Mosalaganti S, Pfeffer S, Hagen WJH, Forster F, Borgnia MJ, Vogel C, Beck M, Bartesaghi A, Silva GM Proc Natl Acad Sci U S A. 2020 Aug 27. pii: 2005301117. doi:, 10.1073/pnas.2005301117. PMID:32855298<ref>PMID:32855298</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6xir" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ribosome 3D structures|Ribosome 3D structures]]
*[[3D sructureseceptor for activated protein kinase C 1|3D sructureseceptor for activated protein kinase C 1]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharomyces cerevisiae]]
[[Category: Bartesaghi A]]
[[Category: Silva GM]]
[[Category: Zhou Y]]