CDC2 activating kinase

Figure 2. Regulators of the Cdc2 protein kinase. Schematic illustration of the regulators of Cdc2 kinase activity. Proteins that are circled indicate proteins that have been identified in higher eukaryotes only the squared proteins have been identified exclusively in the yeast systems. The remaining proteins have been identified in both higher and lower eukaryotes. Protein phosphatases are indicated by p tase.

Draetta, G., and Beach, D. (1988). Activation of cdc2 protein kinase during mitosis in human cells cell cycle-dependent phosphorylation and subunit rearrangement. Cell 54 17-24. 

Positive feedback is also involved in the control of cdc2 by reversible phosphorylation. Thus, cdc2 activates the phosphatase cdc25, which catalyzes the dephosphorylation and concomitant activation of the kinase cdc2. The model based on negative feedback in cyclin-cdc2 interactions can be extended to take this positive feedback into account. Sustained oscillations can be obtained in these conditions [31, 134], but the waveform of cdc2 in the course of oscillations now displays a plateau. This plateau is due to the occurrence of a phenomenon of bistability, which is accompanied by hysteresis, as... 

Graeser R, Franklin RM, Kappes B (1996) Mechanisms of activation of the cdc2-related kinase PfPK5 from Plasmodium falciparum. Mol Biochem Parasitol 79(1) 125-127... 

Le Roch K, Sestier C, Dorin D et al (2000) Activation of a Plasmodium falciparum cdc2-related kinase by heterologous p25 and cyclin H. Functional characterization of a P. falciparum cyclin homologue. J Biol Chem 275(12) 8952-8958... 

Hendrickson M, Madine M, Dalton S, Gautier J. Phosphorylation of MCM4 by cdc2 protein kinase inhibits the activity of the minichromosome maintenance complex. Proc. Natl. Acad. Sci. U.S.A. 1996 93 12223-12228. 

Kasten, M. and Giordano, A. (2001) CdklO, a Cdc2-related kinase, associates with the Ets2 transcription factor and modulates its transactivation activity. Oncogene, 20, 1832-1838. 

P13 acts in the fission yeast cell division cycle. Addition of the proton to the kinase assay in vitro was able to rescue the defect in the Cdc2 mutant kinase activity P13 cont ns two tryptophans (Trp-71 and Trp-82) and seven tyrosine residues. The maximum of the fluorescence emission spectrum b localcd at 336 nm (>., 295 or 275 nm). Thus, tryptophan residues are responsiUe for the protdn fluorescence. Three lifetimes are found for the intensity dec, 0.6,2.9 and 6.1 ns, with fracUonal intensities of0.04,0.32 and 0.64, respectively. 

Yamashita, K. et ah, Okadaic acid, a potent inhibitor of type 1 and type 2 protein phosphatase, activates cdc2/Hl kinase and transiently induces a premature mitosis-like state in BHK21 cells, EMBO J., 9,4331, 1990. 

Pomerance M, Thang MN, Tocque B, Pierre M. 1996. The Ras-GTPase-activating protein SH3 domain is required for Cdc2 activation and mos induction by oncogenic Ras in Xenopus oocytes independently of mitogen-activated protein kinase activation. Mol Cell Biol 16(6) 3179 3186. 

B. Regulators of Cdc2/Cdk2 Protein Kinase Activity Cyclins... 

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