“Understanding the mechanochemical transitions that underlie early embryo development”

During embryogenesis a single fertilized oocyte develops into an adult organism via tightly controlled patterns of cell division, cell polarization and cell movements. These mechanical processes depend on the actomyosin cortex, a thin 2D layer that resides underneath the plasma membrane. Importantly, for normal development the actomyosin cortex in rapidly dividing embryonic cells needs to transition between contractile and non-contractile phases. Surprisingly little is known about how these mechanical transitions are regulated in a developing embryo. To understand mechanical transitions during embryogenesis, I use C. elegans early embryos as a model, and perform quantitative live imaging of the actomyosin cortex as it transitions between contractile and non-contractile phases. In the IMG seminar I will present my recent results in which we demonstrate how two major signaling cascades, Cdc42 and RhoA, affect distinct mechanical phases and the transitions between them.