View source for 6ma1


==Crystal structure of human O-GlcNAc transferase bound to a peptide from HCF-1 pro-repeat 2 (11-26) and inhibitor 4a==
<StructureSection load='6ma1' size='340' side='right'caption='[[6ma1]], [[Resolution|resolution]] 2.75&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6ma1]] 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=6MA1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6MA1 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]] 2.75&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=JA4:N-[(2R)-2-{[(7-chloro-2-oxo-1,2-dihydroquinolin-6-yl)sulfonyl]amino}-2-(2-methoxyphenyl)acetyl]-N-[(thiophen-2-yl)methyl]glycine'>JA4</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=6ma1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ma1 OCA], [https://pdbe.org/6ma1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6ma1 RCSB], [https://www.ebi.ac.uk/pdbsum/6ma1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6ma1 ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/OGT1_HUMAN OGT1_HUMAN] Regulation of OGT activity and altered O-GlcNAcylations are implicated in diabetes and Alzheimer disease. O-GlcNAcylation of AKT1 affects insulin signaling and, possibly diabetes. Reduced O-GlcNAcylations and resulting increased phosphorylations of MAPT/TAU are observed in Alzheimer disease (AD) brain cerebrum.
== Function ==
[https://www.uniprot.org/uniprot/OGT1_HUMAN OGT1_HUMAN] Catalyzes the transfer of a single N-acetylglucosamine from UDP-GlcNAc to a serine or threonine residue in cytoplasmic and nuclear proteins resulting in their modification with a beta-linked N-acetylglucosamine (O-GlcNAc). Glycosylates a large and diverse number of proteins including histone H2B, AKT1, PFKL, KMT2E/MLL5, MAPT/TAU and HCFC1. Can regulate their cellular processes via cross-talk between glycosylation and phosphorylation or by affecting proteolytic processing. Involved in insulin resistance in muscle and adipocyte cells via glycosylating insulin signaling components and inhibiting the 'Thr-308' phosphorylation of AKT1, enhancing IRS1 phosphorylation and attenuating insulin signaling. Involved in glycolysis regulation by mediating glycosylation of 6-phosphofructokinase PFKL, inhibiting its activity. Component of a THAP1/THAP3-HCFC1-OGT complex that is required for the regulation of the transcriptional activity of RRM1. Plays a key role in chromatin structure by mediating O-GlcNAcylation of 'Ser-112' of histone H2B: recruited to CpG-rich transcription start sites of active genes via its interaction with TET proteins (TET1, TET2 or TET3). As part of the NSL complex indirectly involved in acetylation of nucleosomal histone H4 on several lysine residues.<ref>PMID:12150998</ref> <ref>PMID:18288188</ref> <ref>PMID:19451179</ref> <ref>PMID:19377461</ref> <ref>PMID:20018852</ref> <ref>PMID:20018868</ref> <ref>PMID:20200153</ref> <ref>PMID:20824293</ref> <ref>PMID:21285374</ref> <ref>PMID:22121020</ref> <ref>PMID:22923583</ref> <ref>PMID:23353889</ref> <ref>PMID:23222540</ref> <ref>PMID:15361863</ref> <ref>PMID:21240259</ref>   Isoform 2: the mitochondrial isoform (mOGT) is cytotoxic and triggers apoptosis in several cell types including INS1, an insulinoma cell line.<ref>PMID:12150998</ref> <ref>PMID:18288188</ref> <ref>PMID:19451179</ref> <ref>PMID:19377461</ref> <ref>PMID:20018852</ref> <ref>PMID:20018868</ref> <ref>PMID:20200153</ref> <ref>PMID:20824293</ref> <ref>PMID:21285374</ref> <ref>PMID:22121020</ref> <ref>PMID:22923583</ref> <ref>PMID:23353889</ref> <ref>PMID:23222540</ref> <ref>PMID:15361863</ref> <ref>PMID:21240259</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Reversible glycosylation of nuclear and cytoplasmic proteins is an important regulatory mechanism across metazoans. One enzyme, O-linked N-acetylglucosamine transferase (OGT), is responsible for all nucleocytoplasmic glycosylation and there is a well-known need for potent, cell-permeable inhibitors to interrogate OGT function. Here we report the structure-based evolution of OGT inhibitors culminating in compounds with low nanomolar inhibitory potency and on-target cellular activity. In addition to disclosing useful OGT inhibitors, the structures we report provide insight into how to inhibit glycosyltransferases, a family of enzymes that has been notoriously refractory to inhibitor development.

Structure-Based Evolution of Low Nanomolar O-GlcNAc Transferase Inhibitors.,Martin SES, Tan ZW, Itkonen HM, Duveau DY, Paulo JA, Janetzko J, Boutz PL, Tork L, Moss FA, Thomas CJ, Gygi SP, Lazarus MB, Walker S J Am Chem Soc. 2018 Oct 4. doi: 10.1021/jacs.8b07328. PMID:30285435<ref>PMID:30285435</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6ma1" style="background-color:#fffaf0;"></div>

==See Also==
*[[O-GlcNAc transferase 3D structures|O-GlcNAc transferase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Lazarus MB]]
[[Category: Martin SES]]
[[Category: Walker S]]