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Updated: Jun 18, 2025
07:59
Temporal Quantification of MAPK Induced Expression in Single Yeast Cells
Published on: October 4, 2013
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Shared and redundant proteins coordinate signal cross-talk between MAPK pathways in yeast
Shu Zhang1, Hao Wang2, Emily L Sipko1
1Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.
Molecular Biology of the Cell
|July 31, 2024
Summary
Yeast cells coordinate signals using shared components. The Sho1 branch of the high osmolarity glycerol (HOG) pathway uses the Kss1 protein to mediate cross talk with the mating pathway, enabling adaptation to environmental changes.
Area of Science:
- Cellular signaling
- Molecular biology
- Yeast genetics
Background:
- Cells respond to multiple stimuli via signaling pathways.
- Pathways often share components, leading to complex signal integration.
- In yeast, the High Osmolarity Glycerol (HOG) and mating pathways share the MAPK Kss1.
Purpose of the Study:
- Investigate the role of the shared MAPK Kss1 in coordinating HOG and mating pathways.
- Determine how redundant and shared components manage concurrent environmental signals.
- Elucidate the mechanism of cross talk between the HOG and mating pathways.
Main Methods:
- Utilized Saccharomyces cerevisiae as a model organism.
- Activated both HOG and mating pathways simultaneously using salt and pheromone.
- Generated mutant yeast strains lacking specific pathway components (e.g., Kss1, Sln1, Sho1).
- Analyzed MAPK activation, cellular localization, and transcriptional responses.
Main Results:
- The Sho1 branch of the HOG pathway mediates cross talk with the mating pathway via Kss1.
- Kss1 activation leads to a distinct transcriptional program compared to Hog1 and Fus3.
- Demonstrated specific roles for redundant and shared pathway components in signal coordination.
Conclusions:
- Redundant and shared pathway components are crucial for coordinating concurrent signals.
- Sho1 acts as a key mediator of cross talk between osmotic stress and mating pathways.
- Understanding these mechanisms provides insight into cellular adaptation to environmental changes.
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