To understand the emergence of spatiotemporal structures in biological systems remains a
major challenge to this day. Self-organization of a limited number of different agents has
been found to account for structure formation in sea shells, slime mold aggregation, and
bee colonies. On a subcellular level, however, the importance of self-organization of
proteins and other molecules for forming vital structures is still debated. In this talk, I will
discuss recent experimental and theoretical advances indicating that self-organization
plays an important role in cellular processes like cell division and cell locomotion.
Specifically, I will discuss in detail patterns formed by the Min proteins in the bacterium
Escherichia coli in vivo and in vitro. These patterns constitute an important step in the
selection of the cell division site. I will then indicate how similar processes can account for
cytoskeletal polymerization waves observed in animal cells and speculate about their role
for cell locomotion. Together these results show how physical concepts and methods can
help us to understand vital cellular processes.