View source for 4m91


==crystal structure of hN33/Tusc3-peptide 1==
<StructureSection load='4m91' size='340' side='right'caption='[[4m91]], [[Resolution|resolution]] 1.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4m91]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4M91 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4M91 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]] 1.1&#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=4m91 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4m91 OCA], [https://pdbe.org/4m91 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4m91 RCSB], [https://www.ebi.ac.uk/pdbsum/4m91 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4m91 ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/TUSC3_HUMAN TUSC3_HUMAN] Autosomal recessive nonsyndromic intellectual deficit. The disease is caused by mutations affecting the gene represented in this entry.
== Function ==
[https://www.uniprot.org/uniprot/TUSC3_HUMAN TUSC3_HUMAN] Magnesium transporter. May be involved in N-glycosylation through its association with N-oligosaccharyl transferase.<ref>PMID:19717468</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
N-linked glycosylation of proteins in the endoplasmic reticulum (ER) is essential in eukaryotes and catalyzed by oligosaccharyl transferase (OST). Human OST is a hetero-oligomer of seven subunits. The subunit N33/Tusc3 is a tumor suppressor candidate, and defects in the subunit N33/Tusc3 are linked with nonsyndromic mental retardation. Here, we show that N33/Tusc3 possesses a membrane-anchored N-terminal thioredoxin domain located in the ER lumen that may form transient mixed disulfide complexes with OST substrates. X-ray structures of complexes between N33/Tusc3 and two different peptides as model substrates reveal a defined peptide-binding groove adjacent to the active site that can accommodate peptides in opposite orientations. Structural and biochemical data show that N33/Tusc3 prefers peptides bearing a hydrophobic residue two residues away from the cysteine forming the mixed disulfide with N33/Tusc3. Our results support a model in which N33/Tusc3 increases glycosylation efficiency for a subset of human glycoproteins by slowing glycoprotein folding.

Structural basis of substrate specificity of human oligosaccharyl transferase subunit n33/tusc3 and its role in regulating protein N-glycosylation.,Mohorko E, Owen RL, Malojcic G, Brozzo MS, Aebi M, Glockshuber R Structure. 2014 Apr 8;22(4):590-601. doi: 10.1016/j.str.2014.02.013. Epub 2014, Mar 27. PMID:24685145<ref>PMID:24685145</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4m91" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Aebi M]]
[[Category: Brozzo MS]]
[[Category: Glockshuber R]]
[[Category: Malojcic G]]
[[Category: Mohorko E]]
[[Category: Owen RL]]