Rigidity phase transitions in embryo development: from identification to function

The interchange between fluid-like and solid-like tissue states is key for multicellular morphogenesis. Recent biophysical models have quantitatively predicted and experimentally verified tissue material phase transitions, setting tissue rigidity as a bona fide example of a cell collective. The next step is to understand the function of cell collectives in context, and specifically how they respond to- and feedback on- mechanical and biochemical stimuli. In this talk, I will present how rigidity percolation theory can identify in vivo rigidity phase transitions with high spatiotemporal precision during zebrafish morphogenesis. I will further discuss how we can expand this framework to explore the role of phase transitions in key embryogenic processes, such as cell fate acquisition and germ layer formation.