View source for 2ljf


==Monophosphorylated (747pY) beta3 integrin cytoplasmic tail under aqueous conditions==
<StructureSection load='2ljf' size='340' side='right'caption='[[2ljf]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2ljf]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LJF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2LJF FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR, 15 models</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PTR:O-PHOSPHOTYROSINE'>PTR</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=2ljf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ljf OCA], [https://pdbe.org/2ljf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ljf RCSB], [https://www.ebi.ac.uk/pdbsum/2ljf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ljf ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/ITB3_HUMAN ITB3_HUMAN] Defects in ITGB3 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:2392682</ref> <ref>PMID:1371279</ref> <ref>PMID:1602006</ref> <ref>PMID:1438206</ref> <ref>PMID:8781422</ref> <ref>PMID:9376589</ref> <ref>PMID:9215749</ref> <ref>PMID:9790984</ref> <ref>PMID:9684783</ref> <ref>PMID:10233432</ref> <ref>PMID:11588040</ref> <ref>PMID:11897046</ref> <ref>PMID:12083483</ref> <ref>PMID:12353082</ref> <ref>PMID:15583747</ref> <ref>PMID:15634267</ref> <ref>PMID:15748237</ref> 
== Function ==
[https://www.uniprot.org/uniprot/ITB3_HUMAN ITB3_HUMAN] Integrin alpha-V/beta-3 is a receptor for cytotactin, fibronectin, laminin, matrix metalloproteinase-2, osteopontin, osteomodulin, prothrombin, thrombospondin, vitronectin and von Willebrand factor. Integrin alpha-IIb/beta-3 is a receptor for fibronectin, fibrinogen, plasminogen, prothrombin, thrombospondin and vitronectin. Integrins alpha-IIb/beta-3 and alpha-V/beta-3 recognize the sequence R-G-D in a wide array of ligands. Integrin alpha-IIb/beta-3 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 surface. In case of HIV-1 infection, the interaction with extracellular viral Tat protein seems to enhance angiogenesis in Kaposi's sarcoma lesions.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Reversible protein phosphorylation is vital for many fundamental cellular processes. The actual impact of adding and removing phosphate group(s) is 3-fold: changes in the local/global geometry, alterations in the electrostatic potential and, as the result of both, modified protein-target interactions. Here we present a comprehensive structural investigation of the effects of phosphorylation on the conformational as well as functional states of a crucial cell surface receptor, alpha(IIb)beta(3) integrin. We have analyzed phosphorylated (Tyr(747) and Tyr(759)) beta(3) integrin cytoplasmic tail (CT) primarily by NMR, and our data demonstrate that under both aqueous and membrane-mimetic conditions, phosphorylation causes substantial conformational rearrangements. These changes originate from novel ionic interactions and revised phospholipid binding. Under aqueous conditions, the critical Tyr(747) phosphorylation prevents beta(3)CT from binding to its heterodimer partner alpha(IIb)CT, thus likely maintaining an activated state of the receptor. This conclusion was tested in vivo and confirmed by integrin-dependent endothelial cells adhesion assay. Under membrane-mimetic conditions, phosphorylation results in a modified membrane embedding characterized by significant changes in the secondary structure pattern and the overall fold of beta(3)CT. Collectively these data provide unique molecular insights into multiple regulatory roles of phosphorylation.

Tyrosine phosphorylation as a conformational switch: a case study of integrin beta3 cytoplasmic tail.,Deshmukh L, Meller N, Alder N, Byzova T, Vinogradova O J Biol Chem. 2011 Nov 25;286(47):40943-53. doi: 10.1074/jbc.M111.231951. Epub, 2011 Sep 28. PMID:21956114<ref>PMID:21956114</ref>

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

==See Also==
*[[Integrin 3D structures|Integrin 3D structures]]
== References ==
<references/>
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</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Deshmukh L]]
[[Category: Vinogradova O]]