Emily Gehrels – How to create form and dynamics in a living embryo

Aix-Marseille Université

Biological organisms are able to develop from simple eggs to complex adult forms via a series of dynamic rearrangements, during which embryonic tissues generate stress, deform, and flow. What can we learn about the rules and possibilities of autonomous structure formation by studying their development? I will present one such study where we uncover how Drosophila embryos use symmetric forces to create a polarized flow of cells needed to achieve their final form.

Cell flows in the early Drosophila embryo are driven by an interplay between biological signaling and tissue mechanics. Using live imaging, we observe how changes in the presence of force-generating proteins and the geometry of the tissue relate to tissue dynamics at the onset of morphogenesis. We use theoretical and computational methods to model the behavior of the tissue and experimentally challenge our findings using select genetic perturbations of the embryos. With this combination of experimental and modeling approaches, we have uncovered how organized multicellular dynamics emerge from genetic, mechanical, and geometric “information” during early Drosophila development.