Abstract:

Endocytosis and Exocytosis not only play important roles in the transport of critical substances in and out of the cell, but also stabilize the cell shape by promoting irreversible changes in the plasma membrane. Interestingly, recent studies have found that periodic cellular contraction could speed up these processes by producing transient changes in the cell-cell contact lengths, eventually leading to significant morphogenetic changes of the cell. In particular, it has been observed that the formation and pinching-off of cytoplasmic vesicles were triggered by the active contraction. However, the underlying physical mechanisms remain unknown. Here, by treating membrane deformation process as a thermally-assisted escaping from an energy well, a theoretical model is proposed to describe the vesicle formation and pinching-induced plastic length change of the cell-cell contact edge. Corresponding Monte Carlo simulations were also conducted to compare model predictions with a number of experimental observations.