4aka: Difference between revisions

==IPSE alpha-1, an IgE-binding crystallin==

== Structural highlights ==

<table><tr><td colspan='2'>[[4aka]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Schistosoma_mansoni Schistosoma mansoni]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4AKA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4AKA FirstGlance]. <br>

</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=4aka FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4aka OCA], [https://pdbe.org/4aka PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4aka RCSB], [https://www.ebi.ac.uk/pdbsum/4aka PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4aka ProSAT]</span></td></tr>

[https://www.uniprot.org/uniprot/Q869D4_SCHMA Q869D4_SCHMA]  

<div style="background-color:#fffaf0;">

IPSE/alpha-1, the major secretory product of eggs from the parasitic worm Schistosoma mansoni, efficiently triggers basophils to release the immunomodulatory key cytokine interleukin-4. Activation by IPSE/alpha-1 requires the presence of IgE on the basophils, but the detailed molecular mechanism underlying activation is unknown. NMR and crystallographic analysis of IPSEdeltaNLS, a monomeric IPSE/alpha-1 mutant, revealed that IPSE/alpha-1 is a new member of the beta&amp;]gamma]-crystallin superfamily. We demonstrate that this molecule is a general immunoglobulin-binding factor with highest affinity for IgE. NMR binding studies of IPSEdeltaNLS with the 180-kDa molecule IgE identified a large positively charged binding surface that includes a flexible loop, which is unique to the IPSE/alpha-1 crystallin fold. Mutational analysis of amino acids in the binding interface showed that residues contributing to IgE binding are important for IgE-dependent activation of basophils. As IPSE/alpha-1 is unable to cross-link IgE, we propose that this molecule, by taking advantage of its unique IgE-binding crystallin fold, activates basophils by a novel, cross-linking-independent mechanism.

 

A crystallin fold in the interleukin-4-inducing principle of Schistosoma mansoni eggs (IPSE/alpha-1) mediates IgE binding for antigen-independent basophil activation.,Meyer NH, Mayerhofer H, Tripsianes K, Blindow S, Barths D, Mewes A, Weimar T, Kohli T, Bade S, Madl T, Frey A, Haas H, Mueller-Dieckmann J, Sattler M, Schramm G J Biol Chem. 2015 Jul 10. pii: jbc.M115.675066. PMID:26163514<ref>PMID:26163514</ref>

 

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

<div class="pdbe-citations 4aka" style="background-color:#fffaf0;"></div>

[[Category: Large Structures]]