Image based validation of dynamical models for cell reorientation.

Area of Science:

• Cellular dynamics
• Biophysics
• Systems biology

Background:

• Directed cell movement and rapid reorientation are crucial for cellular functions.
• Mathematical models propose diverse regulatory mechanisms for cell reorientation.
• Validating these models against experimental data is essential for scientific rigor.

Purpose of the Study:

• To fit and compare three reaction-diffusion models to experimental data of Dictyostelium amoebae reorienting in response to mechanical shear flow.
• To assess the ability of different models to explain spatio-temporal F-actin dynamics.
• To demonstrate the utility of model selection and identifiability analysis for spatio-temporal data.

Main Methods:

• Fitting reaction-diffusion models to experimental data of Dictyostelium amoebae.
• Utilizing spatio-temporal distributions of fluorescently labeled cortical F-actin as experimental readouts.
• Simultaneously fitting experiments under varied conditions to challenge model robustness.

Main Results:

• The Otsuji model did not provide a satisfactory fit to the experimental data.
• Both Meinhardt and Levchenko models demonstrated equally good fits.
• A reduced two-variable Meinhardt model also provided an excellent fit with unique parameter identifiability.

Conclusions:

• Model selection and identifiability analysis are powerful tools for validating spatio-temporal biological models.
• The study highlights the effectiveness of these analytical approaches for understanding cell reorientation dynamics.
• This work contributes to a more rigorous validation of mathematical models in systems biology.