View source for 9ezg


==Crystal structure of human Casein Kinase II subunit alpha (CK2a1) in complex with 5-((4-((2-aminoethyl)(ethyl)amino)-3-(4H-1,2,4-triazol-4-yl)phenyl)amino)-7-(cyclopropylamino)pyrazolo[1,5-a]pyrimidine-3-carbonitrile==
<StructureSection load='9ezg' size='340' side='right'caption='[[9ezg]], [[Resolution|resolution]] 2.18&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9ezg]] 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=9EZG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9EZG 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]] 2.18&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=A1H8C:5-[[4-[2-azanylethyl(ethyl)amino]-3-(1,2,4-triazol-4-yl)phenyl]amino]-7-(cyclopropylamino)pyrazolo[1,5-a]pyrimidine-3-carbonitrile'>A1H8C</scene>, <scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=9ezg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9ezg OCA], [https://pdbe.org/9ezg PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9ezg RCSB], [https://www.ebi.ac.uk/pdbsum/9ezg PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9ezg ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CSK21_HUMAN CSK21_HUMAN] Catalytic subunit of a constitutively active serine/threonine-protein kinase complex that phosphorylates a large number of substrates containing acidic residues C-terminal to the phosphorylated serine or threonine. Regulates numerous cellular processes, such as cell cycle progression, apoptosis and transcription, as well as viral infection. May act as a regulatory node which integrates and coordinates numerous signals leading to an appropriate cellular response. During mitosis, functions as a component of the p53/TP53-dependent spindle assembly checkpoint (SAC) that maintains cyclin-B-CDK1 activity and G2 arrest in response to spindle damage. Also required for p53/TP53-mediated apoptosis, phosphorylating 'Ser-392' of p53/TP53 following UV irradiation. Can also negatively regulate apoptosis. Phosphorylates the caspases CASP9 and CASP2 and the apoptotic regulator NOL3. Phosphorylation protects CASP9 from cleavage and activation by CASP8, and inhibits the dimerization of CASP2 and activation of CASP8. Regulates transcription by direct phosphorylation of RNA polymerases I, II, III and IV. Also phosphorylates and regulates numerous transcription factors including NF-kappa-B, STAT1, CREB1, IRF1, IRF2, ATF1, SRF, MAX, JUN, FOS, MYC and MYB. Phosphorylates Hsp90 and its co-chaperones FKBP4 and CDC37, which is essential for chaperone function. Regulates Wnt signaling by phosphorylating CTNNB1 and the transcription factor LEF1. Acts as an ectokinase that phosphorylates several extracellular proteins. During viral infection, phosphorylates various proteins involved in the viral life cycles of EBV, HSV, HBV, HCV, HIV, CMV and HPV.<ref>PMID:11239457</ref> <ref>PMID:11704824</ref> <ref>PMID:16193064</ref> <ref>PMID:19188443</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The pyrazolo[1,5-a]pyrimidine scaffold is a promising scaffold to develop potent and selective CSNK2 inhibitors with antiviral activity against beta-coronaviruses. Herein, we describe the discovery of a 1,2,4-triazole group to substitute a key amide group for CSNK2 binding present in many potent pyrazolo[1,5-a]pyrimidine inhibitors. Crystallographic evidence demonstrates that the 1,2,4-triazole replaces the amide in forming key hydrogen bonds with Lys68 and a water molecule buried in the ATP-binding pocket. This isosteric replacement improves potency and metabolic stability at a cost of solubility. Optimization for potency, solubility, and metabolic stability led to the discovery of the potent and selective CSNK2 inhibitor 53. Despite excellent in vitro metabolic stability, rapid decline in plasma concentration of 53 in vivo was observed and may be attributed to lung accumulation, although in vivo pharmacological effect was not observed. Further optimization of this novel chemotype may validate CSNK2 as an antiviral target in vivo.

More than an Amide Bioisostere: Discovery of 1,2,4-Triazole-containing Pyrazolo[1,5-a]pyrimidine Host CSNK2 Inhibitors for Combatting beta-Coronavirus Replication.,Ong HW, Yang X, Smith JL, Dickmander RJ, Brown JW, Havener TM, Taft-Benz S, Howell S, Sanders MK, Capener JL, Counago RM, Chang E, Kramer A, Moorman NJ, Heise M, Axtman AD, Drewry DH, Willson TM J Med Chem. 2024 Jul 25;67(14):12261-12313. doi: 10.1021/acs.jmedchem.4c00962. , Epub 2024 Jul 3. PMID:38959455<ref>PMID:38959455</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9ezg" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Brown JW]]
[[Category: Chang E]]
[[Category: Knapp S]]
[[Category: Kraemer A]]
[[Category: Ong HW]]
[[Category: Willson T]]
[[Category: Yang X]]