Dissertation

Cellular Forces: Adhering, Shaping, Sensing and Dividing

Promotor: Prof.dr. T. Schmidt

Author

H. van Hoorn

Date

26 November 2014

Links

Thesis in Leiden Repository

Life’s building block is a cell. Different cell types are differentiated by specific functional properties. A white blood cell, for instance, can get rid of bacteria and many muscle cells contract together for proper muscle function. Deformation and force exertion play important roles in these processes. Bacteria have to be physically engulfed by the white blood cell, and the muscle cell has to contract in the right way. In this research we measured how much force cells exert and simultaneously visualized specific proteins. A newly developed technique enabled the visualization of the nanometer-structure of cellular adhesions. We also examined the relationship between cellular shape and orientation of an intracellular network of protein (actin). We discovered that the signal of yet another protein (p130Cas) alters the mechanical behavior of the cell when the stiffness outside the cell changes. Finally, we also examined the structure of other proteins (tubulin and H2B) during cell division. In all these processes we measured how much force a cell exerts on its environment. The results provide important insights in the mechanical component of cellular function and their role in life.