Cellular Environment and Phenotypic Heterogeneity: How Data-Driven Modeling Finds the Smoking Gun

Area of Science:

• Cell Biology
• Biophysics
• Systems Biology

Background:

• Cellular phenotypes, particularly stress responses, exhibit significant heterogeneity due to regulatory network properties.
• The extracellular matrix, including collagen type I, is a critical component of the cellular environment influencing cell behavior.

Purpose of the Study:

• To quantify and interpret the influence of collagen type I on the phenotypic heterogeneity of cellular stress responses.
• To elucidate the molecular mechanisms underlying collagen type I-mediated changes in cellular response heterogeneity.

Main Methods:

• Single-cell monitoring techniques to track cellular responses.
• Mathematical modeling of cellular regulatory networks.
• Statistical analysis of phenotypic heterogeneity.
• Biochemical measurements for model validation.

Main Results:

• Detailed statistical characterization of phenotypic heterogeneity in cellular responses.
• Mathematical model explaining heterogeneity through increased average expression of a central regulatory protein.
• Model predictions were validated by biochemical measurements.

Conclusions:

• Collagen type I significantly impacts cellular stress response heterogeneity.
• An increase in the average expression of a central protein is a key mechanism driving these changes.
• The presented framework offers a general methodology for studying phenotypic heterogeneity in cellular responses, exemplified by proteotoxic stress in HeLa cells.