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Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis
Published on: February 16, 2015
ON/OFF and beyond--a boolean model of apoptosis
Rebekka Schlatter1, Kathrin Schmich, Ima Avalos Vizcarra
1Institute for System Dynamics, University of Stuttgart, Stuttgart, Germany. rebekka.schlatter@isys.uni-stuttgart.de
Plos Computational Biology
|December 17, 2009
Summary
This study introduces a Boolean model of apoptosis pathways, revealing complex regulatory mechanisms and feedback loops. The model accurately simulates responses to various stimuli, offering new insights into cell death processes.
Area of Science:
- Cell Biology
- Systems Biology
- Computational Biology
Background:
- Apoptosis is a crucial cellular process regulated by intricate signaling pathways with extensive crosstalk.
- Boolean modeling offers a powerful approach to understanding the qualitative dynamics of complex biological networks.
Purpose of the Study:
- To construct a comprehensive, literature-based Boolean model of intrinsic and extrinsic apoptosis pathways.
- To analyze the regulatory mechanisms and feedback loops governing apoptosis.
- To validate the model's coherence and explore its predictive capabilities.
Main Methods:
- Developed a large-scale, literature-based Boolean model incorporating timescales and multi-value node logic.
- Modeled central intrinsic and extrinsic apoptosis pathways and connected signaling networks.
- Experimentally validated the model's coherence, including UV-B dose-effect in mouse hepatocytes.
Main Results:
- The Boolean model accurately simulates apoptosis network behavior in response to stimuli like Fas ligand, TNF-alpha, UV-B, IL-1beta, and insulin.
- Model analysis highlighted tight regulation through high connectivity, crosstalks, and critical feedback loops.
- An unpredicted feedback from Smac release to RIP was identified, potentially enhancing complex II formation.
Conclusions:
- The developed Boolean model provides a comprehensive and coherent description of apoptosis network dynamics.
- The study offers novel insights into the interplay of pro- and antiapoptotic factors.
- The model serves as a valuable platform for future expansion and investigation of related signaling pathways.
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