Coordination of cell growth and cell division: a mathematical modeling study

Area of Science:

• Cell Biology
• Mathematical Biology
• Biophysics

Background:

• Cell growth and division are coordinated, but the underlying mechanisms remain unclear.
• Understanding the link between cell size and cell cycle progression is crucial for cell biology.

Purpose of the Study:

• To develop a mathematical model predicting cell growth rate based on cell surface area.
• To investigate the relationship between cell growth control and cell division timing.
• To validate the model against experimental data from various cell types.

Main Methods:

• Developed a mathematical model of cell growth signaling pathways.
• Applied the model to analyze cell cycle data from fission yeast, Xenopus laevis, and mammalian cells.
• Integrated the growth model with cell cycle models incorporating 'sizer' and 'timer' phases.

Main Results:

• The model predicts cell growth rate is proportional to cell surface area at birth.
• The model successfully reproduces experimental data on cell cycle time versus cell birth size in fission yeast and Xenopus laevis.
• The model explains cell cycle delays observed in mammalian cells after serum withdrawal.

Conclusions:

• A simple model where growth rate is proportional to surface area after division can explain cell cycle control.
• This finding provides a mechanistic link between cell growth and division, reconciling experimental observations.
• The model offers a framework for understanding cell size regulation and cell cycle progression.