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Heldt2018 - Proliferation-quiescence decision in response to DNA damage

ABSTRACT: Heldt2018 - Proliferation-quiescence decision in response to DNA damage This model is described in the article: A comprehensive model for the proliferation-quiescence decision in response to endogenous DNA damage in human cells. Heldt FS, Barr AR, Cooper S, Bakal C, Novák B. Proc. Natl. Acad. Sci. U.S.A. 2018 Feb; : Abstract: Human cells that suffer mild DNA damage can enter a reversible state of growth arrest known as quiescence. This decision to temporarily exit the cell cycle is essential to prevent the propagation of mutations, and most cancer cells harbor defects in the underlying control system. Here we present a mechanistic mathematical model to study the proliferation-quiescence decision in nontransformed human cells. We show that two bistable switches, the restriction point (RP) and the G1/S transition, mediate this decision by integrating DNA damage and mitogen signals. In particular, our data suggest that the cyclin-dependent kinase inhibitor p21 (Cip1/Waf1), which is expressed in response to DNA damage, promotes quiescence by blocking positive feedback loops that facilitate G1 progression downstream of serum stimulation. Intriguingly, cells exploit bistability in the RP to convert graded p21 and mitogen signals into an all-or-nothing cell-cycle response. The same mechanism creates a window of opportunity where G1 cells that have passed the RP can revert to quiescence if exposed to DNA damage. We present experimental evidence that cells gradually lose this ability to revert to quiescence as they progress through G1 and that the onset of rapid p21 degradation at the G1/S transition prevents this response altogether, insulating S phase from mild, endogenous DNA damage. Thus, two bistable switches conspire in the early cell cycle to provide both sensitivity and robustness to external stimuli. This model is hosted on BioModels Database and identified by: MODEL1703030000. 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: Frank Stefan Heldt

PROVIDER: BIOMD0000000700 | BioModels | 2024-09-02

REPOSITORIES: BioModels

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	BIOMD0000000700?filename=BIOMD0000000700-biopax3.owl	Owl
	BIOMD0000000700?filename=BIOMD0000000700-matlab.m	Other
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	BIOMD0000000700?filename=BIOMD0000000700.ode	Other

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A comprehensive model for the proliferation-quiescence decision in response to endogenous DNA damage in human cells.

Heldt Frank S FS Barr Alexis R AR Cooper Sam S Bakal Chris C Novák Béla B

Proceedings of the National Academy of Sciences of the United States of America 20180220 10

Human cells that suffer mild DNA damage can enter a reversible state of growth arrest known as quiescence. This decision to temporarily exit the cell cycle is essential to prevent the propagation of mutations, and most cancer cells harbor defects in the underlying control system. Here we present a mechanistic mathematical model to study the proliferation-quiescence decision in nontransformed human cells. We show that two bistable switches, the restriction point (RP) and the G1/S transition, medi ...[more]

PMID: 29463760

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