View source for 6pit


==Estrogen Receptor Alpha Ligand Binding Domain Y537S Mutant in Complex with SRC2 Stapled Peptide 41A and Estradiol==
<StructureSection load='6pit' size='340' side='right'caption='[[6pit]], [[Resolution|resolution]] 2.25&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6pit]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6PIT OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6PIT 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]] 2.25&#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>, <scene name='pdbligand=EST:ESTRADIOL'>EST</scene>, <scene name='pdbligand=LOU:3-[(3aR,4S,7S,7aS)-2-(carboxymethyl)-1,3-dioxooctahydro-4H-4,7-epoxyisoindol-4-yl]-L-alanine'>LOU</scene>, <scene name='pdbligand=SCH:S-METHYL-THIO-CYSTEINE'>SCH</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=6pit FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6pit OCA], [https://pdbe.org/6pit PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6pit RCSB], [https://www.ebi.ac.uk/pdbsum/6pit PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6pit ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ESR1_HUMAN ESR1_HUMAN] Nuclear hormone receptor. The steroid hormones and their receptors are involved in the regulation of eukaryotic gene expression and affect cellular proliferation and differentiation in target tissues. Ligand-dependent nuclear transactivation involves either direct homodimer binding to a palindromic estrogen response element (ERE) sequence or association with other DNA-binding transcription factors, such as AP-1/c-Jun, c-Fos, ATF-2, Sp1 and Sp3, to mediate ERE-independent signaling. Ligand binding induces a conformational change allowing subsequent or combinatorial association with multiprotein coactivator complexes through LXXLL motifs of their respective components. Mutual transrepression occurs between the estrogen receptor (ER) and NF-kappa-B in a cell-type specific manner. Decreases NF-kappa-B DNA-binding activity and inhibits NF-kappa-B-mediated transcription from the IL6 promoter and displace RELA/p65 and associated coregulators from the promoter. Recruited to the NF-kappa-B response element of the CCL2 and IL8 promoters and can displace CREBBP. Present with NF-kappa-B components RELA/p65 and NFKB1/p50 on ERE sequences. Can also act synergistically with NF-kappa-B to activate transcription involving respective recruitment adjacent response elements; the function involves CREBBP. Can activate the transcriptional activity of TFF1. Also mediates membrane-initiated estrogen signaling involving various kinase cascades. Isoform 3 is involved in activation of NOS3 and endothelial nitric oxide production. Isoforms lacking one or several functional domains are thought to modulate transcriptional activity by competitive ligand or DNA binding and/or heterodimerization with the full length receptor. Isoform 3 can bind to ERE and inhibit isoform 1.<ref>PMID:7651415</ref> <ref>PMID:10970861</ref> <ref>PMID:9328340</ref> <ref>PMID:10681512</ref> <ref>PMID:10816575</ref> <ref>PMID:11477071</ref> <ref>PMID:11682626</ref> <ref>PMID:15078875</ref> <ref>PMID:16043358</ref> <ref>PMID:15891768</ref> <ref>PMID:16684779</ref> <ref>PMID:18247370</ref> <ref>PMID:17932106</ref> <ref>PMID:19350539</ref> <ref>PMID:20705611</ref> <ref>PMID:21937726</ref> <ref>PMID:21330404</ref> <ref>PMID:22083956</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Macrocyclization can improve bioactive peptide ligands through preorganization of molecular topology, leading to improvement of pharmacologic properties like binding affinity, cell permeability, and metabolic stability. Here we demonstrate that Diels-Alder [4 + 2] cycloadditions can be harnessed for peptide macrocyclization and stabilization within a range of peptide scaffolds and chemical environments. Diels-Alder cyclization of diverse diene-dienophile reactive pairs proceeds rapidly, in high yield and with tunable stereochemical preferences on solid-phase or in aqueous solution. This reaction can be applied alone or in concert with other stabilization chemistries, such as ring-closing olefin metathesis, to stabilize loop, turn, and alpha-helical secondary structural motifs. NMR and molecular dynamics studies of model loop peptides confirmed preferential formation of endo cycloadduct stereochemistry, imparting significant structural rigidity to the peptide backbone that resulted in augmented protease resistance and increased biological activity of a Diels-Alder cyclized (DAC) RGD peptide. Separately, we demonstrated the stabilization of DAC alpha-helical peptides derived from the ERalpha-binding protein SRC2. We solved a 2.25 A cocrystal structure of one DAC helical peptide bound to ERalpha, which unequivocally corroborated endo stereochemistry of the resulting Diels-Alder adduct, and confirmed that the unique architecture of stabilizing motifs formed with this chemistry can directly contribute to target binding. These data establish Diels-Alder cyclization as a versatile approach to stabilize diverse protein structural motifs under a range of chemical environments.

Versatile Peptide Macrocyclization with Diels-Alder Cycloadditions.,Montgomery JE, Donnelly JA, Fanning SW, Speltz TE, Shangguan X, Coukos JS, Greene GL, Moellering RE J Am Chem Soc. 2019 Sep 26. doi: 10.1021/jacs.9b07578. PMID:31523967<ref>PMID:31523967</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6pit" style="background-color:#fffaf0;"></div>

==See Also==
*[[Estrogen receptor 3D structures|Estrogen receptor 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Fanning SW]]
[[Category: Greene GL]]
[[Category: Moellering RE]]
[[Category: Montgomery JE]]