Biochemical Characterization of the Human Cyclin-dependent Protein Kinase Activating Kinase

  title={Biochemical Characterization of the Human Cyclin-dependent Protein Kinase Activating Kinase},
  author={Ann Yee and L. Wu and L. Liu and Ryuji Kobayashi and Yue Xiong and Frederick L. Hall},
  journal={The Journal of Biological Chemistry},
  pages={471 - 477}
  • A. Yee, L. Wu, +3 authors F. Hall
  • Published 1996
  • Biology, Medicine
  • The Journal of Biological Chemistry
The activation of cyclin-dependent protein kinases (Cdks) is dependent upon site-specific phosphorylation and dephosphorylation reactions, as well as positive and negative regulatory subunits. The human Cdk-activating protein kinase (Cak1) is itself a Cdc2-related cyclin-dependent protein kinase that associates with cyclin H. The present study utilized specific anti-Cak1 antibodies and immunoaffinity chromatography to identify additional Cak1-associated proteins and potential target substrates… Expand
Molecular cloning of CDK7-associated human MAT1, a cyclin-dependent kinase-activating kinase (CAK) assembly factor.
Through a large-scale immunopurification of CDK7 complexes and protein microsequencing, a cDNA is isolated that encodes p35 and it is shown that it is the human homologue of Mat1 that is involved in the assembly of CAK, a characteristic feature shared among RING finger proteins. Expand
The cyclin C/Cdk8 kinase.
Observations and the sequence similarity to the kinase/cyclin pair Srb10/Srb11 in S. cerevisiae suggest that cyclin C and Cdk8 control RNA polymerase II function. Expand
Meiotic Expression of the Cyclin H/Cdk7 Complex in Male Germ Cells of the Mouse1
It is shown that cyclin H and Cdk7 are present and during meiosis, form active complexes in testicular cells and are strong candidates for the activating kinase for cyclin A1-associated kinase. Expand
MAT1-Modulated CAK Activity Regulates Cell Cycle G1 Exit
  • Lingtao Wu, Ping Chen, +5 authors T. Triche
  • Medicine, Biology
  • Molecular and Cellular Biology
  • 2001
It is suggested that CAK is involved in the regulation of cell cycle G1 exit while MAT1-modulated CAK formation and CAK phosphorylation of pRb may determine the cell cycle specificity of CAK in G1 progression. Expand
RNA Antisense Abrogation of MAT1 Induces G1 Phase Arrest and Triggers Apoptosis in Aortic Smooth Muscle Cells*
It is shown that abrogation of MAT1 expression retards SMC proliferation and inhibits cell activation from a nonproliferative state, and it is demonstrated that these effects are due to G1 phase arrest and apoptotic cell death. Expand
Cyclin-dependent kinases: initial approaches to exploit a novel therapeutic target.
To address the need for additional chemotypes that may serve as lead structures for drugs that would not have the toxicities associated with flavopiridol, compounds with a similar pattern of cell growth inhibitory activity in the National Cancer Institute's in vitro anticancer drug screen have been recognized and screened for anti-CDK activity in a biochemical screen. Expand
The MAT1 cyclin‐dependent kinase‐activating kinase (CAK) assembly/targeting factor interacts physically with the MCM7 DNA licensing factor
Investigation of the physical interaction between MAT1 and MCM7 in yeast cells and in vitro protein binding assays showed the RING‐finger motif of MAT1 is not required for the interaction withMCM7, while the C‐terminal domain ofMAT1 is indispensable. Expand
Advances in Brief Molecular Cloning of CDK 7-. associated Human MAT 1 , a Cyclin-dependent Kinase activating Kinase ( CAK ) Assembly Factor '
Department of Biochemistry and Biophysics (A. Y., Y. X.J and Curriculum in Molecular Biology and Genetics (M. A. N., Y. XI. University of North Carolina at Chapel Hill. Chapel Hill. North CarolinaExpand
The Novel Human DNA Helicase hFBH1 Is an F-box Protein*
It is shown that hFBH1 exhibited DNA-dependent ATPase and DNA unwinding activities that displace duplex DNA in the 3′ to 5′ direction and is the first F-box protein that possesses intrinsic enzyme activity. Expand
A uniform procedure for the purification of CDK7/CycH/MAT1, CDK8/CycC and CDK9/CycT1
This protocol provides a novel systematic approach for the purification of these three recombinant CDKs and generates large amounts of active recombinant kinases that are devoid of contaminating kinase activities. Expand


Molecular cloning of the human CAK1 gene encoding a cyclin-dependent kinase-activating kinase.
The molecular characterization of (HS)CAK1 should facilitate studies of its physiological regulation, as well as its potential utility as a target for therapeutic intervention in the treatment of proliferative disorders. Expand
Phosphorylation independent activation of human cyclin-dependent kinase 2 by cyclin A in vitro.
Bacterial expression and purification systems for Cdk2 and cyclin A that allow mechanistic studies of the activation process to be performed in the absence of cell extracts are developed and the potential significance of direct activation of Cdk1 by cyclins with respect to regulation of cell cycle progression is discussed. Expand
Activation of cyclin-dependent kinase 4 (cdk4) by mouse MO15-associated kinase.
It is demonstrated that the catalytic subunit of mouse cdc2/cdk2 CAK (a 39-kDa protein designated p39MO15) can assemble with a regulatory protein present in either insect or mammalian cells to generate a CAK activity capable of phosphorylating and enzymatically activating both cdk2 and cdk4 in complexes with their respective cyclin partners. Expand
Identification, assay, and purification of a Cdc2-activating threonine-161 protein kinase from human cells.
Findings identify a human Cdc2-activating kinase as a growth factor-responsive enzyme system that may participate in the acute activation of cyclin-dependent protein kinases observed in mammalian somatic cells. Expand
A novel cyclin associates with M015/CDK7 to form the CDK-activating kinase
CAK is a CDK-cyclin complex implicated in the control of multiple cell cycle transitions, and like other CDKs, MO15/CDK7 contains a conserved threonine required for full activity; mutation of this residue severely reduces CAK activity. Expand
Cell cycle analysis of the activity, subcellular localization, and subunit composition of human CAK (CDK-activating kinase)
A molecular characterization of a human p40MO15 homologue and its associated CAK activity suggests that the phosphorylation state of threonine 161 in p34cdc2 (and the corresponding residue in other cdks) may be regulated primarily by the availability of the cdk/cyclin substrates, and by phosphatase(s). Expand
A cyclin associated with the CDK-activating kinase MO15
This work uses a yeast two-hybrid screen to show that a new human cyclin (cyclin H) is a MO15-associated protein and enhances the kinase activity of MO15 towards Cdk2/cyclin A, demonstrating that a cyclin/kinase complex can function as a regulator of other cyclin-dependent kinases complexes, and suggesting that cyclin /kinase cascades may exist. Expand
CAK, the p34cdc2 activating kinase, contains a protein identical or closely related to p40MO15.
It is confirmed here that CAK is a protein kinase and its purification over 13,000‐fold from Xenopus egg extracts shows that it contains a protein identical or closely related to the previously identified Xenopus MO15 gene: p40 MO15 copurifies with CAK, and an antiserum to p40MO15 specifically depletes cAK activity. Expand
Cell cycle regulation of CDK2 activity by phosphorylation of Thr160 and Tyr15.
The activity of a subpopulation of CDK2 molecules is inhibited at a time in the cell cycle when overallCDK2 activity is increased, and phosphorylation on the inhibitory sites T14 and Y15 is also maximal during S phase and G2. Expand
The cdc2‐related protein p40MO15 is the catalytic subunit of a protein kinase that can activate p33cdk2 and p34cdc2.
It is speculated that, like p33cdk2 and p34cdc2, p40MO15 requires activation by phosphorylation and association with a companion subunit, and it is concluded that p40 MO15 corresponds to CAK (CDc2/CDk2 activating kinase) and is therefore related to cdc2‐related protein kinase. Expand