Systems Biology: A New Integrative Science for the 21st Century
Wednesday, January 24, 2007
Presented by the New York Academy of Sciences
Host: David Botstein, Lewis-Sigler Institute for Integrative Genomics, Princeton University
Speakers: Saeed Tavazoie, Princeton University; Michael Elowitz, California Institute of Technology
The New Vistas Lecture Series has been created to celebrate the Academy's move to our new downtown home. In this series, the Academy has invited highly accomplished scientists to serve as hosts for an evening of "science at the frontiers." Each evening will feature talks by two up-and-coming scientists whose work has been identified by the host as exceptionally worthy of the spotlight. New Vistas Series is Free to Non-Members.
This evening, David Botstein, director of the Lewis-Sigler Institute for Integrative Genomics at Princeton University and a pioneer in the development of methods for genetic mapping that made the Human Genome Project possible, moderates a discussion with two leaders in the growing field of systems biology.
Saeed Tavazoie, Princeton University:
"A post-genomic perspective on bacterial behavior"
Our modern molecular understanding of bacterial behavior is based almost entirely on a handful of model organisms that together represent only a small fraction of genetic and phenotypic diversity within the microbial biosphere. Furthermore, studies in the best model systems such as E. coli have historically focused on a set of environmental conditions defined more by convenience of laboratory growth and pre-conceived notions of nutrition and stress, rather than ecologically relevant environments and transitions within those environments. In fact, free-living bacteria live in complex and highly structured habitats that have shaped the underlying molecular networks over geological time-scales. At the highest level, the organization of these networks reflects an "internal model" of the outside world that generates optimal behaviors in response to the incoming stream of sensory information. As such, any interpretation of behaviors, and inferences regarding their fitness advantage, has to be placed within the context of this internal model. A major focus of my research group has been the development of genome-wide technologies, conceptual frameworks, and computational methods in order to: 1) rapidly reveal the genetic basis of bacterial phenotypes, 2) map out sensory integration and computations in signaling and transcriptional networks, and 3) explore the micro-evolutionary adaptation of regulatory networks in response to changes in the environment. The application of these tools allows us to rapidly explore the molecular foundation of a rich repertoire of behaviors in bacteria, revealing their higher-level organization into an internal model of the bacterium's ecological niche.
Michael Elowitz, California Institute of Technology:
"The noisy dynamics of gene circuits in individual living cells"
Living cells differentiate into diverse cell types, keep track of time, and communicate with one another. To do so, they use genetic "circuits" composed of interacting genes and proteins. What features of these circuits allow them to operate reliably, to generate variability in cell populations, and to continue to evolve new functions? By analyzing the dynamics of natural and synthetic gene circuits in individual living cells using time-lapse movies, we and others have begun to address these fundamental questions. I will describe this recent work, and its implications for understanding and controlling cellular behavior.
Saeed Tavazoie is an associate professor in the Department of Molecular Biology at Princeton, and a member of the Lewis-Sigler Institute for Integrative Genomics. Studying DNA transcriptional elements and networks of genes, he is working to understand the process through which genetic information maps to a phenotype. He