Dataset Information

Ciliberto2003 - CyclinE / Cdk2 timer in the cell cycle of Xenopus laevis embryo

ABSTRACT: Ciliberto2003 - CyclinE / Cdk2 timer in the cell cycle of Xenopus laevis embryo This model is described in the article: A kinetic model of the cyclin E/Cdk2 developmental timer in Xenopus laevis embryos. Ciliberto A, Petrus MJ, Tyson JJ, Sible JC. Biophys. Chem. 2003 Jul; 104(3): 573-589 Abstract: Early cell cycles of Xenopus laevis embryos are characterized by rapid oscillations in the activity of two cyclin-dependent kinases. Cdk1 activity peaks at mitosis, driven by periodic degradation of cyclins A and B. In contrast, Cdk2 activity oscillates twice per cell cycle, despite a constant level of its partner, cyclin E. Cyclin E degrades at a fixed time after fertilization, normally corresponding to the midblastula transition. Based on published data and new experiments, we constructed a mathematical model in which: (1) oscillations in Cdk2 activity depend upon changes in phosphorylation, (2) Cdk2 participates in a negative feedback loop with the inhibitory kinase Wee1; (3) cyclin E is cooperatively removed from the oscillatory system; and (4) removed cyclin E is degraded by a pathway activated by cyclin E/Cdk2 itself. The model's predictions about embryos injected with Xic1, a stoichiometric inhibitor of cyclin E/Cdk2, were experimentally validated. This model is hosted on BioModels Database and identified by: BIOMD0000000697. To cite BioModels Database, please use: Chelliah V et al. BioModels: ten-year anniversary. Nucl. Acids Res. 2015, 43(Database issue):D542-8. To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to CC0 Public Domain Dedication for more information.

SUBMITTER: Vijayalakshmi Chelliah

PROVIDER: BIOMD0000000697 | BioModels | 2024-09-02

REPOSITORIES: BioModels

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			Action	DRS
	BIOMD0000000697?filename=BIOMD0000000697-biopax2.owl	Owl
	BIOMD0000000697?filename=BIOMD0000000697-biopax3.owl	Owl
	BIOMD0000000697?filename=BIOMD0000000697-matlab.m	Other
	BIOMD0000000697?filename=BIOMD0000000697-octave.m	Other
	BIOMD0000000697?filename=BIOMD0000000697.m	Other

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A kinetic model of the cyclin E/Cdk2 developmental timer in Xenopus laevis embryos.

Ciliberto Andrea A Petrus Matthew J MJ Tyson John J JJ Sible Jill C JC

Biophysical chemistry 20030701 3

Early cell cycles of Xenopus laevis embryos are characterized by rapid oscillations in the activity of two cyclin-dependent kinases. Cdk1 activity peaks at mitosis, driven by periodic degradation of cyclins A and B. In contrast, Cdk2 activity oscillates twice per cell cycle, despite a constant level of its partner, cyclin E. Cyclin E degrades at a fixed time after fertilization, normally corresponding to the midblastula transition. Based on published data and new experiments, we constructed a ma ...[more]

PMID: 12914904

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