4f7s
From Proteopedia
Crystal structure of human CDK8/CYCC in the DMG-in conformation
Structural highlights
Function[CDK8_HUMAN] Component of the Mediator complex, a coactivator involved in regulated gene transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. Mediator is recruited to promoters by direct interactions with regulatory proteins and serves as a scaffold for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. Phosphorylates the CTD (C-terminal domain) of the large subunit of RNA polymerase II (RNAp II), which may inhibit the formation of a transcription initiation complex. Phosphorylates CCNH leading to down-regulation of the TFIIH complex and transcriptional repression. Recruited through interaction with MAML1 to hyperphosphorylate the intracellular domain of NOTCH, leading to its degradation.[1] [2] [CCNC_HUMAN] Component of the Mediator complex, a coactivator involved in regulated gene transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. Mediator is recruited to promoters by direct interactions with regulatory proteins and serves as a scaffold for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. Binds to and activates cyclin-dependent kinase CDK8 that phosphorylates the CTD (C-terminal domain) of the large subunit of RNA polymerase II (RNAp II), which may inhibit the formation of a transcription initiation complex.[3] [4] Publication Abstract from PubMedIn contrast with the very well explored concept of structure-activity relationship, similar studies are missing for the dependency between binding kinetics and compound structure of a protein ligand complex, the structure-kinetic relationship. Here, we present a structure-kinetic relationship study of the cyclin-dependent kinase 8 (CDK8)/cyclin C (CycC) complex. The scaffold moiety of the compounds is anchored in the kinase deep pocket and extended with diverse functional groups toward the hinge region and the front pocket. These variations can cause the compounds to change from fast to slow binding kinetics, resulting in an improved residence time. The flip of the DFG motif ("DMG" in CDK8) to the inactive DFG-out conformation appears to have relatively little influence on the velocity of binding. Hydrogen bonding with the kinase hinge region contributes to the residence time but has less impact than hydrophobic complementarities within the kinase front pocket. Structure-kinetic relationship study of CDK8/CycC specific compounds.,Schneider EV, Bottcher J, Huber R, Maskos K, Neumann L Proc Natl Acad Sci U S A. 2013 May 14;110(20):8081-6. doi:, 10.1073/pnas.1305378110. Epub 2013 Apr 29. PMID:23630251[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||||
