Computer Simulation of Actin Polymerization in Cellular Protrusion

Abstract: Motility or spontaneous motion of eukaryotic cells, such as white blood cells, has been extensively studied in the recent literature. A mechanism has been established based on polymerization of actin filaments that pushes the cell wall forwards. However, many features of this phenomenon remain incompletely understood and more insights from modeling is desirable. We study the problem of understanding the origin and magnitude of the velocity achieved by the moving cells, and compare it with existing experimental results. We have developed and simulated a simplified model based on the relevant features of eukaryotic protrusion, formulating main elements required to describe the cellular motility. The main simplification is the isolation of a few actin filaments, whereas other similar models have previously been built on more complicated cases of polymer ensembles. The strength of the simplified model is that it clarifies the actual e ffective elements of cellular protrusion. A computer program simulates the growth of an actin polymer behind a cellular membrane and delivers the protrusion speed of the eukaryotic. We also construct a real time 3D graphical representation of the movement process. The results obtained are in reasonable agreement with experimental results for the cell velocity. The agreement is actually improved compared to previous studies of more complicated models, indicating that our simplified model indeed seems to work very well. Moreover, the detailed graphical representation highlights the process in greater detail than has previously been achieved.