View source for 5y03


==Galectin-13/Placental Protein 13 variant R53H crystal structure==
<StructureSection load='5y03' size='340' side='right'caption='[[5y03]], [[Resolution|resolution]] 2.12&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5y03]] is a 1 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=5Y03 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5Y03 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]] 2.12&#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=5y03 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5y03 OCA], [https://pdbe.org/5y03 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5y03 RCSB], [https://www.ebi.ac.uk/pdbsum/5y03 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5y03 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PP13_HUMAN PP13_HUMAN] Binds beta-galactoside and lactose. Strong inducer of T-cell apoptosis.<ref>PMID:10527825</ref> <ref>PMID:19497882</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
During pregnancy, placental protein-13 (galectin-13) is highly expressed in the placenta and fetal tissue, and less so in maternal serum that is related to pre-eclampsia. To understand galectin-13 function at the molecular level, we solved its crystal structure and discovered that its dimer is stabilized by two disulfide bridges between Cys136 and Cys138 and six hydrogen bonds involving Val135, Val137, and Gln139. Native PAGE and gel filtration demonstrate that this is not a crystallization artifact because dimers also form in solution. Our biochemical studies indicate that galectin-13 ligand binding specificity is different from that of other galectins in that it does not bind beta-galactosides. This is partly explained by the presence of Arg53 rather than His53 at the bottom of the carbohydrate binding site in a position that is crucial for interactions with beta-galactosides. Mutating Arg53 to histidine does not re-establish normal beta-galactoside binding, but rather traps cryoprotectant glycerol molecules within the ligand binding site in crystals of the R53H mutant. Moreover, unlike most other galectins, we also found that GFP-tagged galectin-13 is localized within the nucleus of HeLa and 293 T cells. Overall, galectin-13 appears to be a new type of prototype galectin with distinct properties.

Galectin-13, a different prototype galectin, does not bind beta-galacto-sides and forms dimers via intermolecular disulfide bridges between Cys-136 and Cys-138.,Su J, Wang Y, Si Y, Gao J, Song C, Cui L, Wu R, Tai G, Zhou Y Sci Rep. 2018 Jan 17;8(1):980. doi: 10.1038/s41598-018-19465-0. PMID:29343868<ref>PMID:29343868</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5y03" style="background-color:#fffaf0;"></div>

==See Also==
*[[Galectin 3D structures|Galectin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Su J]]
[[Category: Wang Y]]