View source for 4bcg


==Structure of CDK9 in complex with cyclin T and a 2-amino-4-heteroaryl- pyrimidine inhibitor==
<StructureSection load='4bcg' size='340' side='right'caption='[[4bcg]], [[Resolution|resolution]] 3.08&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4bcg]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4BCG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4BCG FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=T3C:2-[[3-(1,4-DIAZEPAN-1-YL)PHENYL]AMINO]-4-[4-METHYL-2-(METHYLAMINO)-1,3-THIAZOL-5-YL]PYRIMIDINE-5-CARBONITRILE'>T3C</scene></td></tr>
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=TPO:PHOSPHOTHREONINE'>TPO</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1pf6|1pf6]], [[4bcf|4bcf]], [[4bch|4bch]], [[4bci|4bci]], [[4bcj|4bcj]], [[4bck|4bck]], [[4bcm|4bcm]], [[4bcn|4bcn]], [[4bco|4bco]], [[4bcp|4bcp]], [[4bcq|4bcq]]</div></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=4bcg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4bcg OCA], [https://pdbe.org/4bcg PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4bcg RCSB], [https://www.ebi.ac.uk/pdbsum/4bcg PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4bcg ProSAT]</span></td></tr>
</table>
== Disease ==
[[https://www.uniprot.org/uniprot/CDK9_HUMAN CDK9_HUMAN]] Note=Chronic activation of CDK9 causes cardiac myocyte enlargement leading to cardiac hypertrophy, and confers predisposition to heart failure. 
== Function ==
[[https://www.uniprot.org/uniprot/CDK9_HUMAN CDK9_HUMAN]] Protein kinase involved in the regulation of transcription. Member of the cyclin-dependent kinase pair (CDK9/cyclin-T) complex, also called positive transcription elongation factor b (P-TEFb), which facilitates the transition from abortive to productive elongation by phosphorylating the CTD (C-terminal domain) of the large subunit of RNA polymerase II (RNAP II) POLR2A, SUPT5H and RDBP. This complex is inactive when in the 7SK snRNP complex form. Phosphorylates EP300, MYOD1, RPB1/POLR2A and AR, and the negative elongation factors DSIF and NELF. Regulates cytokine inducible transcription networks by facilitating promoter recognition of target transcription factors (e.g. TNF-inducible RELA/p65 activation and IL-6-inducible STAT3 signaling). Promotes RNA synthesis in genetic programs for cell growth, differentiation and viral pathogenesis. P-TEFb is also involved in cotranscriptional histone modification, mRNA processing and mRNA export. Modulates a complex network of chromatin modifications including histone H2B monoubiquitination (H2Bub1), H3 lysine 4 trimethylation (H3K4me3) and H3K36me3; integrates phosphorylation during transcription with chromatin modifications to control co-transcriptional histone mRNA processing. The CDK9/cyclin-K complex has also a kinase activity towards CTD of RNAP II and can substitute for CDK9/cyclin-T P-TEFb in vitro. Replication stress response protein; the CDK9/cyclin-K complex is required for genome integrity maintenance, by promoting cell cycle recovery from replication arrest and limiting single-stranded DNA amount in response to replication stress, thus reducing the breakdown of stalled replication forks and avoiding DNA damage. In addition, probable function in DNA repair of isoform 2 via interaction with KU70/XRCC6. Promotes cardiac myocyte enlargement. RPB1/POLR2A phosphorylation on 'Ser-2' in CTD activates transcription. AR phosphorylation modulates AR transcription factor promoter selectivity and cell growth. DSIF and NELF phosphorylation promotes transcription by inhibiting their negative effect. The phosphorylation of MYOD1 enhances its transcriptional activity and thus promotes muscle differentiation.<ref>PMID:9857195</ref> <ref>PMID:10393184</ref> <ref>PMID:10574912</ref> <ref>PMID:10912001</ref> <ref>PMID:10757782</ref> <ref>PMID:11145967</ref> <ref>PMID:11112772</ref> <ref>PMID:11575923</ref> <ref>PMID:11884399</ref> <ref>PMID:11809800</ref> <ref>PMID:12037670</ref> <ref>PMID:15564463</ref> <ref>PMID:14701750</ref> <ref>PMID:17956865</ref> <ref>PMID:18362169</ref> <ref>PMID:19844166</ref> <ref>PMID:19575011</ref> <ref>PMID:20493174</ref> <ref>PMID:20930849</ref> <ref>PMID:20081228</ref> <ref>PMID:20980437</ref> <ref>PMID:21127351</ref>  [[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 ==
Cancer cells often have a high demand for antiapoptotic proteins in order to resist programmed cell death. CDK9 inhibition selectively targets survival proteins and reinstates apoptosis in cancer cells. We designed a series of 4-thiazol-2-anilinopyrimidine derivatives with functional groups attached to the C5-position of the pyrimidine or to the C4-thiazol moiety and investigated their effects on CDK9 potency and selectivity. One of the most selective compounds, 12u inhibits CDK9 with IC(50) = 7 nM and shows over 80-fold selectivity for CDK9 versus CDK2. X-ray crystal structures of 12u bound to CDK9 and CDK2 provide insights into the binding modes. This work, together with crystal structures of selected inhibitors in complex with both enzymes described in a companion paper, (34) provides a rationale for the observed SAR. 12u demonstrates potent anticancer activity against primary chronic lymphocytic leukemia cells with a therapeutic window 31- and 107-fold over those of normal B- and T-cells.

Substituted 4-(thiazol-5-yl)-2-(phenylamino)pyrimidines are highly active CDK9 inhibitors: synthesis, X-ray crystal structures, structure-activity relationship, and anticancer activities.,Shao H, Shi S, Huang S, Hole AJ, Abbas AY, Baumli S, Liu X, Lam F, Foley DW, Fischer PM, Noble M, Endicott JA, Pepper C, Wang S J Med Chem. 2013 Feb 14;56(3):640-59. doi: 10.1021/jm301475f. Epub 2013 Jan 25. PMID:23301767<ref>PMID:23301767</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4bcg" 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: Human]]
[[Category: Large Structures]]
[[Category: Baumli, S]]
[[Category: Endicott, J A]]
[[Category: Hole, A J]]
[[Category: Noble, M E.M]]
[[Category: Wang, S]]
[[Category: Cdk-cyclin complex]]
[[Category: Structure-based drug design]]
[[Category: Transcription-protein binding]]
[[Category: Transferase-cell cycle complex]]