A Biomechanics Model to Simulate the Entire Cytokinesis Process

In all eukaryotes, cytokinesis is a big deformation process that a mother cell is divided to two daughter cells. It is involved in many mechanical actions, such as active contraction of microfilament, viscous flow of cytoplasm and big deformation of cortical membrane. In order to attain a better understanding of the cytokinesis process and corroborate a mechanical mechanism, various theoretical models were proposed. Recent work of cell mitosis experiments have approved that the site of contractile ring is determined by the biochemical stimulus from asters of the mitotic apparatus, actin and myosin assembly relate to the motion of membrane phospholipid, local distribution and arrangement of microfilament cytoskeleton is different with cytokinesis phases. A biomechanics model is constructed to simulate the entire process from the biochemical stimulus of asters to cytokinesis finish. In the model, three points are considered, one is biochemical stimulus effect from asters during forming initial contractile ring; two is the surface tension include two parts: membrane tension due to passive deformation and active contract force of actin filament whose effect is determined by microfilaments redistribution and rearrangement; three is the microfilament is linked to the membrane through big molecules. The model could explain microfilaments ¹dynamics in the cell membrane during cytokinesis and satisfactorily predicts the cell deformation. These results suggested that actin filament redistribution and reorientation might play a crucial role in cell division. Introducing the biochemical stimulus, this model is closely and comprehensively describes cytokinesis process.