View source for 2ru2


==NMR solution structure of [G5,T7,S9]-oxytocin==
<StructureSection load='2ru2' size='340' side='right'caption='[[2ru2]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2ru2]] is a 1 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2RU2 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2RU2 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR, 20 models</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NH2:AMINO+GROUP'>NH2</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=2ru2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ru2 OCA], [https://pdbe.org/2ru2 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ru2 RCSB], [https://www.ebi.ac.uk/pdbsum/2ru2 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ru2 ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Cyclotides are plant peptides comprising a circular backbone and three conserved disulfide bonds that confer them with exceptional stability. They were originally discovered in Oldenlandia affinis based on their use in traditional African medicine to accelerate labor. Recently, cyclotides have been identified in numerous plant species of the coffee, violet, cucurbit, pea, potato, and grass families. Their unique structural topology, high stability, and tolerance to sequence variation make them promising templates for the development of peptide-based pharmaceuticals. However, the mechanisms underlying their biological activities remain largely unknown; specifically, a receptor for a native cyclotide has not been reported hitherto. Using bioactivity-guided fractionation of an herbal peptide extract known to indigenous healers as "kalata-kalata," the cyclotide kalata B7 was found to induce strong contractility on human uterine smooth muscle cells. Radioligand displacement and second messenger-based reporter assays confirmed the oxytocin and vasopressin V1a receptors, members of the G protein-coupled receptor family, as molecular targets for this cyclotide. Furthermore, we show that cyclotides can serve as templates for the design of selective G protein-coupled receptor ligands by generating an oxytocin-like peptide with nanomolar affinity. This nonapeptide elicited dose-dependent contractions on human myometrium. These observations provide a proof of concept for the development of cyclotide-based peptide ligands.

Oxytocic plant cyclotides as templates for peptide G protein-coupled receptor ligand design.,Koehbach J, O'Brien M, Muttenthaler M, Miazzo M, Akcan M, Elliott AG, Daly NL, Harvey PJ, Arrowsmith S, Gunasekera S, Smith TJ, Wray S, Goransson U, Dawson PE, Craik DJ, Freissmuth M, Gruber CW Proc Natl Acad Sci U S A. 2013 Dec 24;110(52):21183-8. doi:, 10.1073/pnas.1311183110. Epub 2013 Nov 18. PMID:24248349<ref>PMID:24248349</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2ru2" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Craik D]]
[[Category: Harvey P]]