View source for 9p97


==CryoEM structure of the closed integrin alphaEbeta7 bound to fab LF61==
<StructureSection load='9p97' size='340' side='right'caption='[[9p97]], [[Resolution|resolution]] 2.92&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9p97]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9P97 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9P97 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]] 2.92&#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=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=9p97 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9p97 OCA], [https://pdbe.org/9p97 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9p97 RCSB], [https://www.ebi.ac.uk/pdbsum/9p97 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9p97 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ITAE_HUMAN ITAE_HUMAN] Integrin alpha-E/beta-7 is a receptor for E-cadherin. It mediates adhesion of intra-epithelial T-lymphocytes to epithelial cell monolayers.
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== Publication Abstract from PubMed ==
Integrins bind ligands between their alpha (alpha) and beta (beta) subunits and transmit signals through conformational changes. Early in chordate evolution, some alpha subunits acquired an "inserted" (I) domain that expanded integrin's ligand-binding repertoire but obstructed the ancestral ligand pocket, seemingly blocking conventional integrin activation. Here, we compare cryo-electron microscopy structures of apo and ligand-bound states of the I domain-containing alphaEbeta(7) integrin and the I domain-lacking alpha(4)beta(7) integrin to illuminate how the I domain intrinsically mimics an extrinsic ligand to preserve integrin function. We trace the I domain's evolutionary origin to an ancestral collagen-collagen interaction domain, identifying an ancient molecular exaptation that facilitated integrin activation immediately upon I domain insertion. Our analyses reveal the evolutionary and biochemical basis of expanded cellular communication in vertebrates.

Molecular exaptation by the integrin alphaI domain.,Hollis JA, Chan MC, Malik HS, Campbell MG Sci Adv. 2025 Sep 12;11(37):eadx9567. doi: 10.1126/sciadv.adx9567. Epub 2025 Sep , 10. PMID:40929264<ref>PMID:40929264</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9p97" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Mus musculus]]
[[Category: Campbell MG]]
[[Category: Hollis JA]]