3:30–4:30 pm Maria Goeppert-Mayer Lecture Hall
Reconstituted Clocks
Michael Rust, University of Chicago
Living cells contain thousands of interacting components that have been sculpted by an evolutionary process to participate in overlapping and interlocking feedback loops. The result is a molecular network that can robust organize physiology in space and time, but the interdependence of components can make traditional genetic analysis extremely difficult. I will describe ongoing work by my lab and others to extend the classical approach of biochemical reconstitution--combining well-defined mixtures of biological molecules ex vivo to recapitulate life-like behavior. Missing or poorly understood biology can then be found in the gaps between the behavior of the reconstituted system and the living cell. I will focus on circadian rhythms, endogenous near-24 hour nonlinear oscillators that synchronize with the day-night cycle. This reconstitution approach has allowed the field to pinpoint the biochemical reactions responsible for measuring the length of the day. We have used this methodology to illuminate how the oscillator is embedded in a larger metabolic feedback loop, to isolate molecules that carry output information from the oscillator, and to study the interaction between the cell cycle and the circadian clock