2k1a: Difference between revisions
No edit summary |
No edit summary |
||
Line 1: | Line 1: | ||
==Bicelle-embedded integrin alpha(IIB) transmembrane segment== | ==Bicelle-embedded integrin alpha(IIB) transmembrane segment== | ||
<StructureSection load='2k1a' size='340' side='right'caption='[[2k1a | <StructureSection load='2k1a' size='340' side='right'caption='[[2k1a]]' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[2k1a]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/ | <table><tr><td colspan='2'>[[2k1a]] 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=2K1A OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2K1A FirstGlance]. <br> | ||
</td></tr><tr id=' | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</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=2k1a FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2k1a OCA], [https://pdbe.org/2k1a PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2k1a RCSB], [https://www.ebi.ac.uk/pdbsum/2k1a PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2k1a ProSAT]</span></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=2k1a FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2k1a OCA], [https://pdbe.org/2k1a PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2k1a RCSB], [https://www.ebi.ac.uk/pdbsum/2k1a PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2k1a ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Disease == | == 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 == | == 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. | |||
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
Line 37: | Line 37: | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
[[Category: | [[Category: Homo sapiens]] | ||
[[Category: Large Structures]] | [[Category: Large Structures]] | ||
[[Category: Dua | [[Category: Dua V]] | ||
[[Category: Lau | [[Category: Lau T-L]] | ||
[[Category: Ulmer | [[Category: Ulmer TS]] | ||
Latest revision as of 22:08, 29 May 2024
Bicelle-embedded integrin alpha(IIB) transmembrane segmentBicelle-embedded integrin alpha(IIB) transmembrane segment
Structural highlights
DiseaseITA2B_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] FunctionITA2B_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. 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 PubMedIntegrin cell-adhesion receptors transduce signals bidirectionally across the plasma membrane via the single-pass transmembrane segments of each alpha and beta subunit. While the beta3 transmembrane segment consists of a linear 29-residue alpha-helix, the structure of the alphaIIb transmembrane segment reveals a linear 24-residue alpha-helix (Ile-966 -Lys-989) followed by a backbone reversal that packs Phe-992-Phe-993 against the transmembrane helix. The length of the alphaIIb transmembrane helix implies the absence of a significant transmembrane helix tilt in contrast to its partnering beta3 subunit. Sequence alignment shows Gly-991-Phe-993 to be fully conserved among all 18 human integrin alpha subunits, suggesting that their unusual structural motif is prototypical for integrin alpha subunits. The alphaIIb transmembrane structure demonstrates a level of complexity within the membrane that is beyond simple transmembrane helices and forms the structural basis for assessing the extent of structural and topological rearrangements upon alphaIIb-beta3 association, i.e. integrin transmembrane signaling. Structure of the integrin alphaIIb transmembrane segment.,Lau TL, Dua V, Ulmer TS J Biol Chem. 2008 Jun 6;283(23):16162-8. Epub 2008 Apr 16. PMID:18417472[20] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
|