View source for 8gcd


==Full length Integrin AlphaIIbBeta3 in inactive state==
<StructureSection load='8gcd' size='340' side='right'caption='[[8gcd]], [[Resolution|resolution]] 2.97&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8gcd]] 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=8GCD OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8GCD 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]] 2.97&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</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=8gcd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8gcd OCA], [https://pdbe.org/8gcd PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8gcd RCSB], [https://www.ebi.ac.uk/pdbsum/8gcd PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8gcd ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/ITA2B_HUMAN ITA2B_HUMAN] Defects in ITGA2B are a cause of Glanzmann thrombasthenia (GT) [MIM:[https://omim.org/entry/273800 273800]; also known as thrombasthenia of Glanzmann and Naegeli. GT is the most common inherited disease of platelets. It is an autosomal recessive disorder characterized by mucocutaneous bleeding of mild-to-moderate severity and the inability of this integrin to recognize macromolecular or synthetic peptide ligands. GT has been classified clinically into types I and II. In type I, platelets show absence of the glycoprotein IIb/beta-3 complexes at their surface and lack fibrinogen and clot retraction capability. In type II, the platelets express the glycoprotein IIb/beta-3 complex at reduced levels (5-20% controls), have detectable amounts of fibrinogen, and have low or moderate clot retraction capability. The platelets of GT 'variants' have normal or near normal (60-100%) expression of dysfunctional receptors.<ref>PMID:8282784</ref> <ref>PMID:7508443</ref> <ref>PMID:7706461</ref> <ref>PMID:8704171</ref> <ref>PMID:9215749</ref> <ref>PMID:9473221</ref> <ref>PMID:9763559</ref> <ref>PMID:9722314</ref> <ref>PMID:9734640</ref> <ref>PMID:9920835</ref> <ref>PMID:10607701</ref> <ref>PMID:11798398</ref> <ref>PMID:12181054</ref> <ref>PMID:12083483</ref> <ref>PMID:12424194</ref> <ref>PMID:12506038</ref> <ref>PMID:15099289</ref> <ref>PMID:15219201</ref> <ref>PMID:17018384</ref> 
== Function ==
[https://www.uniprot.org/uniprot/ITA2B_HUMAN ITA2B_HUMAN] Integrin alpha-IIb/beta-3 is a receptor for fibronectin, fibrinogen, plasminogen, prothrombin, thrombospondin and vitronectin. It recognizes the sequence R-G-D in a wide array of ligands. It recognizes the sequence H-H-L-G-G-G-A-K-Q-A-G-D-V in fibrinogen gamma chain. Following activation integrin alpha-IIb/beta-3 brings about platelet/platelet interaction through binding of soluble fibrinogen. This step leads to rapid platelet aggregation which physically plugs ruptured endothelial cell surface.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Integrin alphaIIbbeta3 is the key receptor regulating platelet retraction and accumulation and a proven drug-target for antithrombotic therapies. Here we resolve the cryo-EM structures of the full-length alphaIIbbeta3, which covers three distinct states along the activation pathway. Firstly, we obtain the alphaIIbbeta3 structure at 3 A resolution in the inactive state, revealing the overall topology of the heterodimer with the transmembrane (TM) helices and the ligand-binding domain tucked in a specific angle proximity to the TM region. After the addition of a Mn(2+) agonist, we resolve two coexisting structures representing two new states between inactive and active state. Our structures show conformational changes of the alphaIIbbeta3 activating trajectory and a unique twisting of the integrin legs, which is required for platelets accumulation. Our structure provides direct structural evidence for how the lower legs are involved in full-length integrin activation mechanisms and offers a new strategy to target the alphaIIbbeta3 lower leg.

Full-length alphaIIbbeta3 cryo-EM structure reveals intact integrin initiate-activation intrinsic architecture.,Huo T, Wu H, Moussa Z, Sen M, Dalton V, Wang Z Structure. 2024 Jul 11;32(7):899-906.e3. doi: 10.1016/j.str.2024.03.006. Epub , 2024 Apr 4. PMID:38579706<ref>PMID:38579706</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8gcd" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Huo T]]
[[Category: Wang Z]]
[[Category: Wu H]]