An intriguing aspect of multicellular organisms is the fact that there are a wide variety of different cell types, this despite the fact that each and every cell carries the same genetic information. One of the key mechanisms giving rise to distinct cellular identities is particular “decisions” that are made about which genes to express at different times and places in an organism’s history. Interestingly, decision making is not restricted to multicellular organisms, nor even to eukaryotic cells. Indeed, the modern theory of gene regulation was born out of efforts to understand how bacterial cells decide which sugars to utilize at any given time. In this talk, I will describe the ways in which statistical mechanics can be used to examine the regulatory processes that take place in the lives of cells. These simple models result in surprising predictions and I will also describe our experimental efforts to probe this rich behavior both in test tubes and in living cells.
Rob Phillips is a Professor of Applied Physics at California Institute of Technology.