View source for 2qkt


==Crystal Structure of the 5th PDZ domain of InaD==
<StructureSection load='2qkt' size='340' side='right'caption='[[2qkt]], [[Resolution|resolution]] 2.05&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2qkt]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Drosophila_melanogaster Drosophila melanogaster]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2QKT OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2QKT FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.05&#8491;</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=2qkt FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2qkt OCA], [https://pdbe.org/2qkt PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2qkt RCSB], [https://www.ebi.ac.uk/pdbsum/2qkt PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2qkt ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/INAD_DROME INAD_DROME] Involved in the negative feedback regulation of the light-activated signaling cascade in photoreceptors through a calcium-mediated process. Interacts with tetrapeptide ligand located in C-terminal sequence of 3 key components of the visual cascade, tethering them and forming a macromolecular signaling phototransduction complex.<ref>PMID:7826638</ref> <ref>PMID:11342563</ref> 
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/qk/2qkt_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2qkt ConSurf].
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== Publication Abstract from PubMed ==
The INAD scaffold organizes a multiprotein complex that is essential for proper visual signaling in Drosophila photoreceptor cells. Here we show that one of the INAD PDZ domains (PDZ5) exists in a redox-dependent equilibrium between two conformations--a reduced form that is similar to the structure of other PDZ domains, and an oxidized form in which the ligand-binding site is distorted through formation of a strong intramolecular disulfide bond. We demonstrate transient light-dependent formation of this disulfide bond in vivo and find that transgenic flies expressing a mutant INAD in which PDZ5 is locked in the reduced state display severe defects in termination of visual responses and visually mediated reflex behavior. These studies demonstrate a conformational switch mechanism for PDZ domain function and suggest that INAD behaves more like a dynamic machine rather than a passive scaffold, regulating signal transduction at the millisecond timescale through cycles of conformational change.

Dynamic scaffolding in a G protein-coupled signaling system.,Mishra P, Socolich M, Wall MA, Graves J, Wang Z, Ranganathan R Cell. 2007 Oct 5;131(1):80-92. PMID:17923089<ref>PMID:17923089</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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== References ==
<references/>
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</StructureSection>
[[Category: Drosophila melanogaster]]
[[Category: Large Structures]]
[[Category: Ranganathan R]]
[[Category: Socolich M]]