S18-03 Shaping the early amniote embryo: An object-oriented model based on defined cell behaviours

The ability to maintain a proportionate body plan in individuals of different sizes is essential for proper development. Despite wide interest, little is known about the mechanisms underlying scaling with size. I will discuss our efforts to reveal the molecular basis for scaling in different systems. A general ‘‘Expansion– Repression’’ feedback topology will be presented, which ensures scaling for a wide range of parameters and sizes through an effective implementation of an integral-feedback controller. Integralfeedback presents a key concept in engineering, and is likely to be instrumental also for maintaining biological homeostasis.