View source for 9eok


==Minus end of the vertebrate gamma-tubulin ring complex-capped microtubule==
<StructureSection load='9eok' size='340' side='right'caption='[[9eok]], [[Resolution|resolution]] 23.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9eok]] is a 42 chain structure with sequence from [https://en.wikipedia.org/wiki/Xenopus_laevis Xenopus laevis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9EOK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9EOK 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]] 23&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GDP:GUANOSINE-5-DIPHOSPHATE'>GDP</scene>, <scene name='pdbligand=GTP:GUANOSINE-5-TRIPHOSPHATE'>GTP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=TA1:TAXOL'>TA1</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=9eok FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9eok OCA], [https://pdbe.org/9eok PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9eok RCSB], [https://www.ebi.ac.uk/pdbsum/9eok PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9eok ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q5U4V6_XENLA Q5U4V6_XENLA] Tubulin is the major constituent of microtubules, a cylinder consisting of laterally associated linear protofilaments composed of alpha- and beta-tubulin heterodimers. Microtubules grow by the addition of GTP-tubulin dimers to the microtubule end, where a stabilizing cap forms. Below the cap, tubulin dimers are in GDP-bound state, owing to GTPase activity of alpha-tubulin.[RuleBase:RU000352]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The gamma-tubulin ring complex (gamma-TuRC) is a structural template for de novo microtubule assembly from alpha/beta-tubulin units. The isolated vertebrate gamma-TuRC assumes an asymmetric, open structure deviating from microtubule geometry, suggesting that gamma-TuRC closure may underlie regulation of microtubule nucleation. Here, we isolate native gamma-TuRC-capped microtubules from Xenopus laevis egg extract nucleated through the RanGTP-induced pathway for spindle assembly and determine their cryo-EM structure. Intriguingly, the microtubule minus end-bound gamma-TuRC is only partially closed and consequently, the emanating microtubule is locally misaligned with the gamma-TuRC and asymmetric. In the partially closed conformation of the gamma-TuRC, the actin-containing lumenal bridge is locally destabilised, suggesting lumenal bridge modulation in microtubule nucleation. The microtubule-binding protein CAMSAP2 specifically binds the minus end of gamma-TuRC-capped microtubules, indicating that the asymmetric minus end structure may underlie recruitment of microtubule-modulating factors for gamma-TuRC release. Collectively, we reveal a surprisingly asymmetric microtubule minus end protofilament organisation diverging from the regular microtubule structure, with direct implications for the kinetics and regulation of nucleation and subsequent modulation of microtubules during spindle assembly.

gamma-TuRC asymmetry induces local protofilament mismatch at the RanGTP-stimulated microtubule minus end.,Vermeulen BJ, Bohler A, Gao Q, Neuner A, Zupa E, Chu Z, Wurtz M, Jakle U, Gruss OJ, Pfeffer S, Schiebel E EMBO J. 2024 May;43(10):2062-2085. doi: 10.1038/s44318-024-00087-4. Epub 2024 Apr , 10. PMID:38600243<ref>PMID:38600243</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9eok" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Xenopus laevis]]
[[Category: Pfeffer S]]
[[Category: Vermeulen BJA]]