Physical aspects of cell and tissue elongation*

Shaping cells and tissues requires a tight spatiotemporal control of several physical quantities during morphogenesis. Actively-generated stresses as well as material properties and growth can all be tuned in space and time and contribute to building functional structures, with multiple molecular processes and feedbacks enabling the spatiotemporal regulation of these physical fields. In this talk, I will focus on cell and tissue elongation and highlight a common physical mechanism of elongating individual wall cells and animal embryonic tissues. I will present the results of theoretical studies of the dynamics of growth of mating projections in budding yeast cells and also of body axis elongation in zebrafish embryos, using coarse grained approaches and basic physical principles. Our results, which are in agreement with experimental observations, show that the existence of spatially and temporally regulated fluid-to-solid transitions in the structures being sculpted is essential for both cell and tissue elongation.

This work was done in collaboration with Carlos Gomez, Michael Trogdon, Linda R. Petzold, Tau-Mu Yi, Emmet K. Carn, Payam Rowghanian, Georgina Stooke-Vaughan, and Sangwoo Kim.