Abstract

The cell nucleus is more solid like than the rest of the cell. Whilst the cytoplasm deforms relatively easily, the nucleus shows more resistance to deformation. The elastic properties of the nucleus are thought to be determined by the nuclear lamina, a thin shell made up of protein intermediate filaments called lamins. The mechanical properties of the nucleus restrict the ability of migratory cells to pass through small constrictions. Experiments on migrating cells in microfluidic devices have shown that cancer cells are able to deform their nucleus and move through small constrictions more easily than non cancerous cells. I will present theoretical work that we have done to to model the nucleus and calculate the traction force field required to deform the nucleus so a cell can pass through a constriction. We have developed an algorithm to calculate the traction force field from experimental images of deforming nuclei. The results of our calculations depend on the details of the mechanical properties of the model nucleus. I will therefore discuss the mechanical properties of the nucleus and ways we could improve our model. Finally, I will discuss the active mechanisms by which cells may generate the necessary forces to deform the nucleus.