Department of Physics
Division of Basic Sciences
Fred Hutchinson Cancer Research Center
Web page: http://www.smoldyn.org/andrews/index.html
I am fascinated by how the highly structured macroscopic world of living organisms is built from the stochastic microscopic world of individual molecules.
I study spatial organization on cellular size scales using detailed biochemical simulations. This work addresses questions such as how E. coli bacteria center their cell-division plane, how macromolecular crowding affects chemical reaction rates within cells, and why yeast cells secrete proteases that degrade pheromone signals. I also do a substantial amount of algorithm and software development to support this research. The resulting Smoldyn simulator is now widely used and has become the most widely cited particle-based simulator available. Upcoming software development will focus on filaments because these are essential biological components but hard to model with current tools.
How much information can cells transmit through their signaling systems? And how have the systems evolved to improve information transmission? I am pursuing these questions in cell signaling research with my mentor, Roger Brent. We recently completed a survey of the mechanisms that could enable cells to exhibit "dose-response alignment", which is a phenomenon in which multiple stages of cell signaling pathways are similarly sensitive to stimuli. We found the surprising result that "push-pull" mechanisms are almost uniquely capable of yielding dose-response alignment, suggesting that they may be under-appreciated biochemical mechanisms. We are also investigating the information transmission implications of different dose-response relationships in order to better understand how cells can convey information precisely using inherently noisy biochemical reactions.