3tnh

CDK9/cyclin T in complex with CAN508

spinqualitylabelsall models 3tnh, resolution 3.20Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3tnh is a 2 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: F18 NonStd Res: TPO Related: 3tni, 3tnw Gene: CDC2L4, CDK9 (HUMAN), CCNT1 (HUMAN) Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Disease [CDK9_HUMAN] Note=Chronic activation of CDK9 causes cardiac myocyte enlargement leading to cardiac hypertrophy, and confers predisposition to heart failure. Function [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. [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. Publication Abstract from PubMed CDK9 is the kinase of positive transcription elongation factor b and facilitates the transition of paused RNA polymerase II to processive transcription elongation. CDK9 is a validated target for the treatment of cancer, cardiac hypertrophy, and human immunodeficiency virus. Here we analyze different CDK9/cyclin T variants to identify a form of the complex amenable to use in inhibitor design. To demonstrate the utility of this system, we have determined the crystal structures of CDK9/cyclin T and CDK2/cyclin A bound to the CDK9-specific inhibitor CAN508. Comparison of the structures reveals CDK9-specific conformational changes and identifies a CDK9-specific hydrophobic pocket, adjacent to the alphaC-helix. By comparison with a previously published structure of CDK9/cyclin T/human immunodeficiency virus TAT we find that the CDK9 alphaC-helix has a degree of conformational variability that has the potential to be exploited for inhibitor design. The CDK9 C-helix Exhibits Conformational Plasticity That May Explain the Selectivity of CAN508.,Baumli S, Hole AJ, Noble ME, Endicott JA ACS Chem Biol. 2012 Feb 10. PMID:22292676 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

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