School of Physics Soft Condensed Matter & Biophysics Seminar: Prof. Erel Levine, Harvard University

Exposure to high temperatures has an adverse effect on cellular processes and results in activation of the cellular heat shock response (HSR), a highly conserved program of inducible genes to maintain protein homeostasis. Quantitative studies of the HSR in singe cell organisms have been instrumental to our understanding of the principles of control and adaptation, and exemplify the utility of tools from control theory, dynamical systems, and formal models in molecular systems biology. HSR in multicellular organisms, however, adds another layer of complexity: while different cells may be exposed to different environmental cues and different stability requirements, organismic adaptation requires coordination and corporation among cells and tissues.

Here we use time-resolved longitudinal imaging of HSR in C. elegans to study its dynamics and coordination. By applying precise spatiotemporal perturbation we show that somatic cells integrate local sensation with systemic signals to control the time and level of response. We describe a robust dynamical pattern of activation and deactivation, and implicate sensory neurons in initiating these dynamics. A distributed modeling approach assigns distinct functionalities to the presumed coupling modes in driving specialized but coordinated response.