1m8o: Difference between revisions
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==Platelet integrin alfaIIb-beta3 cytoplasmic domain== | ==Platelet integrin alfaIIb-beta3 cytoplasmic domain== | ||
<StructureSection load='1m8o' size='340' side='right' caption='[[1m8o]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''> | <StructureSection load='1m8o' size='340' side='right' caption='[[1m8o]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[1m8o]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. The February 2011 RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Integrin'' by David Goodsell is [http://dx.doi.org/10.2210/rcsb_pdb/mom_2011_2 10.2210/rcsb_pdb/mom_2011_2]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1M8O OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1M8O FirstGlance]. <br> | <table><tr><td colspan='2'>[[1m8o]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. The February 2011 RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Integrin'' by David Goodsell is [http://dx.doi.org/10.2210/rcsb_pdb/mom_2011_2 10.2210/rcsb_pdb/mom_2011_2]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1M8O OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1M8O FirstGlance]. <br> | ||
</td></tr><tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1m8o FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1m8o OCA], [http://pdbe.org/1m8o PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1m8o RCSB], [http://www.ebi.ac.uk/pdbsum/1m8o PDBsum]</span></td></tr> | </td></tr><tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1m8o FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1m8o OCA], [http://pdbe.org/1m8o PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1m8o RCSB], [http://www.ebi.ac.uk/pdbsum/1m8o PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1m8o ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Disease == | == Disease == | ||
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Check<jmol> | Check<jmol> | ||
<jmolCheckbox> | <jmolCheckbox> | ||
<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/m8/1m8o_consurf.spt"</scriptWhenChecked> | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/m8/1m8o_consurf.spt"</scriptWhenChecked> | ||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | ||
<text>to colour the structure by Evolutionary Conservation</text> | <text>to colour the structure by Evolutionary Conservation</text> | ||
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</div> | </div> | ||
<div class="pdbe-citations 1m8o" style="background-color:#fffaf0;"></div> | <div class="pdbe-citations 1m8o" style="background-color:#fffaf0;"></div> | ||
== References == | == References == | ||
<references/> | <references/> |
Revision as of 11:08, 31 January 2018
Platelet integrin alfaIIb-beta3 cytoplasmic domainPlatelet integrin alfaIIb-beta3 cytoplasmic domain
Structural highlights
Disease[ITA2B_HUMAN] Defects in ITGA2B are a cause of Glanzmann thrombasthenia (GT) [MIM: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.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [ITB3_HUMAN] Defects in ITGB3 are a cause of Glanzmann thrombasthenia (GT) [MIM: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.[20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] Function[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. [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. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedActivation of the ligand binding function of integrin heterodimers requires transmission of an "inside-out" signal from their small intracellular segments to their large extracellular domains. The structure of the cytoplasmic domain of a prototypic integrin alpha(IIb)beta(3) has been solved by NMR and reveals multiple hydrophobic and electrostatic contacts within the membrane-proximal helices of its alpha and the beta cytoplasmic tails. The interface interactions are disrupted by point mutations or the cytoskeletal protein talin that are known to activate the receptor. These results provide a structural mechanism by which a handshake between the alpha and the beta cytoplasmic tails restrains the integrin in a resting state and unclasping of this interaction triggers the inside-out conformational signal that leads to receptor activation. A structural mechanism of integrin alpha(IIb)beta(3) "inside-out" activation as regulated by its cytoplasmic face.,Vinogradova O, Velyvis A, Velyviene A, Hu B, Haas T, Plow E, Qin J Cell. 2002 Sep 6;110(5):587-97. PMID:12230976[37] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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