View source for 1sem


==STRUCTURAL DETERMINANTS OF PEPTIDE-BINDING ORIENTATION AND OF SEQUENCE SPECIFICITY IN SH3 DOMAINS==
<StructureSection load='1sem' size='340' side='right'caption='[[1sem]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1sem]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Caenorhabditis_elegans Caenorhabditis elegans] 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=1SEM OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1SEM 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&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ACE:ACETYL+GROUP'>ACE</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=1sem FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1sem OCA], [https://pdbe.org/1sem PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1sem RCSB], [https://www.ebi.ac.uk/pdbsum/1sem PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1sem ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/SEM5_CAEEL SEM5_CAEEL] Acts both in vulval induction and sex myoblast migration. Presumably interacts with the kinase receptor let-23 and with a target that modifies the Ras-like protein let-60.
== 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/se/1sem_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=1sem ConSurf].
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== Publication Abstract from PubMed ==
The Src-homology-3 (SH3) domains of the Caenorhabditis elegans protein SEM-5 and its human and Drosophila homologues, Grb2 and Drk (refs 1-4), bind proline-rich sequences found in the nucleotide-exchange factor Sos as part of their proposed function linking receptor tyrosine kinase activation to Ras activation. Here we report the crystal structure at 2.0 A resolution of the carboxy-terminal SH3 domain from SEM-5 complexed to the mSos-derived amino-acid sequence PPPVPPRRR. The peptide is found to bind in an orientation ('minus') that is precisely opposite to that observed previously ('plus' orientation) in other SH3-peptide complexes. This novel ability of peptide-recognition proteins to recognize peptides in two distinct modes may play an important role in the signalling specificity of pathways involving SH3 domains. Comparison of this structure with other SH3 complexes reveals how a conserved binding face can be used to recognize peptides in different orientations, and why the Sos peptide binds in this particular orientation.

Structural determinants of peptide-binding orientation and of sequence specificity in SH3 domains.,Lim WA, Richards FM, Fox RO Nature. 1994 Nov 24;372(6504):375-9. PMID:7802869<ref>PMID:7802869</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1sem" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Caenorhabditis elegans]]
[[Category: Large Structures]]
[[Category: Mus musculus]]
[[Category: Fox RO]]
[[Category: Lim WA]]
[[Category: Richards FM]]