Harvard University Department of Physics

The development, homeostasis and evolution of organisms are highly complex phenomena that span many scales of time and space. Cellular components (such as genes and proteins) strongly interact with each other to process information to execute developmental programs and robust response to their environment. One approach we take is to study quantitatively small subsets of components  and the interactions among them. We aim to characterize the elementary building blocks of cellular networks, understand their functions and  limitations, and derive design principles. In particular, our lab is interested in the combined action of different modes of regulation, such as global and specific, transcriptional and post-transcrptional, etc.

However, many biological processes are not limited to a small subset of interactions, and are better described as collective phenomena.  We thus need to complement our studies with a more global, phenomenological or statistical, approach. To bridge the gap between small circuits and collective behavior, we will focus on the way by which cells assume different roles and different states in a multi-cellular community. These may be bacterial cells in a community structure or in an animal host, germ cells in the gonads of a worm (the roundworm C. elegans), or adult cells in a regenerating animal (the flatworm S. mediterranea).

Our studies combine theoretical approaches (deriving from statistical mechanics, condensed matter physics and dynamical systems) with experimental methods of molecular biology, imaging, and large-scale approaches.