"A Physical Approach to Organismal Development" Understanding how the physical form of an organism emerges is a central goal of developmental biology. That said, understanding the spatio-temporal dynamics of development from a list of participating genes and molecules is difficult. Recent advances in live-imaging give us a view into organismal development at scales at which physical form and pattern are manifest - scales much larger than molecules. We pursue a phenomenological dynamical description, inspired by their successes in the study of condensed matter, which we show to provide a surprising amount of insight into microscopic mechanisms and striking macroscopic transitions. Working towards such mathematical descriptions I will present our work in the rearrangement of cellular lattices, termed cell-intercalation. These local rearrangements result in the alteration of tissue shape and the emergent changes in embryonic form - morphogenesis. Relying on empirical analyses of live fluorescent microscopy of Drosophila Germ Band Extension (Lecuit Lab, Marseilles) our work explores the generic features of the coupling between mechanics and chemistry. This culminates in a simple geometric picture of tissue dynamics whose most central predictions we validate empirically.
Lunch at 11:45, Talk at 12:00 noon