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Updated: Jun 24, 2026
07:59
Temporal Quantification of MAPK Induced Expression in Single Yeast Cells
Published on: October 4, 2013
How can yeast cells decide between three activated MAP kinase pathways? A model approach.
1Department of Biology, University of Bremen, D-22334 Bremen, Germany.
Journal of Theoretical Biology
|March 27, 2009
Summary
Yeast cells activate multiple MAP kinase pathways simultaneously. Mathematical modeling reveals osmotic stress response (Hog1 pathway) often dominates, while pheromone response (Fus3 pathway) exhibits unique excitability.
Area of Science:
- Cellular signaling
- Systems biology
- Yeast genetics
Background:
- Yeast Saccharomyces cerevisiae utilizes three key MAP kinase pathways: Fus3 (pheromone), Kss1 (starvation), and Hog1 (osmotic stress).
- Understanding cross-talk and simultaneous activation of these pathways is crucial for cell fate determination.
Purpose of the Study:
- To investigate the response of yeast MAP kinase pathways upon simultaneous activation.
- To model the kinetic interactions and feedback loops within and between these pathways.
Main Methods:
- Development of a kinetic model based on known molecular interactions of yeast MAPK pathways.
- Simulation of simultaneous pathway activations under various conditions.
Main Results:
- The osmotic stress response (Hog1 pathway) is preferentially activated when co-stimulated with other pathways.
- Low nitrogen response (Kss1 pathway) dominates over pheromone response (Fus3 pathway) under co-stimulation.
- Fus3 pathway exhibits excitability, characterized by rapid self-amplification upon sufficient pheromone stimulation.
Conclusions:
- Yeast MAP kinase pathways exhibit complex cross-talk and hierarchical activation dynamics.
- Pathway dominance and excitability are key features influencing cellular response to multiple stimuli.
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