View source for 4bcf


==Structure of CDK9 in complex with cyclin T and a 2-amino-4-heteroaryl- pyrimidine inhibitor==
<StructureSection load='4bcf' size='340' side='right'caption='[[4bcf]], [[Resolution|resolution]] 3.01&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4bcf]] 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=4BCF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4BCF 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]] 3.011&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=T6Q:2-[[3-(4-ETHANOYL-1,4-DIAZEPAN-1-YL)PHENYL]AMINO]-4-[4-METHYL-2-(METHYLAMINO)-1,3-THIAZOL-5-YL]PYRIMIDINE-5-CARBONITRILE'>T6Q</scene>, <scene name='pdbligand=TPO:PHOSPHOTHREONINE'>TPO</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=4bcf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4bcf OCA], [https://pdbe.org/4bcf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4bcf RCSB], [https://www.ebi.ac.uk/pdbsum/4bcf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4bcf ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CCNT1_HUMAN CCNT1_HUMAN] Regulatory subunit of the cyclin-dependent kinase pair (CDK9/cyclin-T1) complex, also called positive transcription elongation factor B (P-TEFb), which is proposed to facilitate the transition from abortive to productive elongation by phosphorylating the CTD (carboxy-terminal domain) of the large subunit of RNA polymerase II (RNA Pol II). In case of HIV or SIV infections, binds to the transactivation domain of the viral nuclear transcriptional activator, Tat, thereby increasing Tat's affinity for the transactivating response RNA element (TAR RNA). Serves as an essential cofactor for Tat, by promoting RNA Pol II activation, allowing transcription of viral genes.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Cyclin-dependent kinase 9/cyclin T, the protein kinase heterodimer that constitutes positive transcription elongation factor b, is a well-validated target for treatment of several diseases, including cancer and cardiac hypertrophy. In order to aid inhibitor design and rationalise the basis for CDK9 selectivity, we have studied the CDK-binding properties of six different members of a 4-(thiazol-5-yl)-2-(phenylamino)pyrimidine-5-carbonitrile series that bind to both CDK9/cyclin T and CDK2/cyclin A. We find that for a given CDK, the melting temperature of a CDK/cyclin/inhibitor complex correlates well with inhibitor potency, suggesting that differential scanning fluorimetry (DSF) is a useful orthogonal measure of inhibitory activity for this series. We have used DSF to demonstrate that the binding of these compounds is independent of the presence or absence of the C-terminal tail region of CDK9, unlike the binding of the CDK9-selective inhibitor 5,6-dichlorobenzimida- zone-1-beta-D-ribofuranoside (DRB). Finally, based on 11 co-crystal structures bound to CDK9/cyclin T or CDK2/cyclin A, we conclude that selective inhibition of CDK9/cyclin T by members of the 4-(thiazol-5-yl)-2-(phenylamino)pyrimidine-5-carbonitrile series results from the relative malleability of the CDK9 active site, rather than from the formation of specific polar contacts.

Comparative structural and functional studies of 4-(thiazol-5-yl)-2-(phenylamino)pyrimidine-5-carbonitrile CDK9 inhibitors suggest the basis for isotype selectivity.,Hole A, Baumli S, Shao H, Shi S, Pepper C, Fischer PM, Wang S, Endicott JA, Noble M J Med Chem. 2012 Dec 20. PMID:23252711<ref>PMID:23252711</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4bcf" style="background-color:#fffaf0;"></div>

==See Also==
*[[Cyclin 3D structures|Cyclin 3D structures]]
*[[Cyclin-dependent kinase 3D structures|Cyclin-dependent kinase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Baumli S]]
[[Category: Endicott JA]]
[[Category: Hole AJ]]
[[Category: Noble MEM]]
[[Category: Wang S]]