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13:19
The Use of Chemostats in Microbial Systems Biology
Published on: October 14, 2013
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Systems Level Analysis of the Yeast Osmo-Stat.
Soheil Rastgou Talemi1,2, Carl-Fredrik Tiger3, Mikael Andersson3
1Institut für Experimentelle Innere Medizin, Medizinische Fakultät, Otto-von-Guericke-Universität, Magdeburg, Germany.
Scientific Reports
|August 13, 2016
Summary
Yeast adaptation to osmotic stress involves the High Osmolarity Glycerol (HOG) and Cell Wall Integrity (CWI) pathways. Our study reveals HOG primarily mediates adaptation, with minimal direct crosstalk between the pathways.
Area of Science:
- Cellular Biology
- Biochemistry
- Systems Biology
Background:
- Organisms adapt to environmental stress via signaling pathways.
- Pathway crosstalk orchestrates cellular responses to multiple stimuli.
- The High Osmolarity Glycerol (HOG) and Cell Wall Integrity (CWI) pathways in yeast manage osmotic stress adaptation.
Purpose of the Study:
- Investigate mechanisms of crosstalk between yeast HOG and CWI pathways.
- Quantitatively test hypotheses regarding HOG and CWI pathway crosstalk.
- Elucidate yeast osmo-homeostasis regulatory mechanisms.
Main Methods:
- Ensemble modeling combined with experimental investigations.
- Quantitative analysis of signaling pathway interactions.
- Yeast osmo-sensing and adaptation studies.
Main Results:
- CWI pathway activation shows a variable volume-dependent threshold; HOG pathway activation uses a fixed volume-dependent threshold.
- Little to no direct crosstalk observed between HOG and CWI pathways.
- The HOG pathway predominantly mediates adaptation to both hyper- and hypo-osmotic stress.
Conclusions:
- Yeast osmo-homeostasis is largely regulated by the HOG pathway.
- The HOG and CWI pathways exhibit distinct activation thresholds.
- New hypotheses regarding osmo-sensing mechanisms were formulated.
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