Systems Biology of Cell Polarization

Cell polarization, in which substances within the cell become non-uniformly distributed, underlies many fundamental biological processes: cell division, cell motility and cell fate specification. The establishment and maintenance of cell polarity is critical to normal cell function, and it relies on a highly coordinated network including processes of signal transduction, membrane trafficking and cytoskeletal dynamics. Due to the variability and uncertainty of the stimuli, cell polarization also has challenging performance objectives including the ability to detect and respond to changes in stimuli and the ability to filter out noise present in the networks to retain stability and robustness.

In this talk, I will present our study on a model system for cell polarization: budding yeast cells. We use mathematical modeling, along with experiments, to investigate the robustness of cell polarization in yeast cells from a systems point of view. The mechanisms for cell polarization, the adaptivity and noise filtering strategies will be discussed. In addition, I will present our results on the morphological changes induced by cell polarity, and possible polarization mechanisms through organizing microdomains on the cell membrane.