主题：General principles for timing and oscillations in stochastic reaction systems
报告人：Prof. Johan Paulsson, Department of Systems Biology, Harvard University
Precise timing can be advantageous in many biological processes but is difficult to achieve because chemical reactions often produce exponentially distributed waiting times for individual events. I will discuss hard bounds on timing and the phase-drift of oscillators in reaction networks with finite numbers of molecules, based on analytical theory for classes of stochastic processes. Based on this theory, I then show how we designed and built a series of ultra-precise synthetic gene oscillators, some of which can oscillate for 500 cell generations without entrainment before drifting out of phase with even half a period. Finally, I will show how some natural systems use the same simple but counterintuitive principles to achieve timing in cell fate decisions, and how these are easily missed in deterministic modeling frameworks.