Cortical Actomyosin Dynamics in Development and Morphogenesis – CADMO

The cortical actomyosin cytoskeleton is a major determinant of the mechanical properties of embryonic cells and tissues. Spatial and temporal modulations of these properties define the mechanical landscape that drives morphogenesis. Yet, an integrated view linking the biochemical properties of the cortex, the structures it then assembles and their mechanical properties is still missing. Here, taking C. elegans as a paradigm, we intend to characterize how from the local biochemical dynamics of the cortex in vivo emerge the mechanical and structural macroscale properties of the cortex.
Following four major directions, we will:
1. proceed to a careful description of the mechanical, structural and dynamical properties of essential cortical protein in a simple system, the 1-cell stage embryo. Combining single-molecule and super-resolution imaging techniques with mechanical measurements we will link the enzymology of the cortex in a live embryo with the structure and mechanical properties.
2. experimentally perturb the system to analyze the mechanisms underlying actomyosin adaptation in face of mechanical and biochemical perturbations (homeostasis).
3. approach the complexity of this system. On the one hand, we will use proteomics to unravel the biochemical complexity of cortical assemblies. On the other we will develop a computational model to integrate our complex experimental data in a quantitative framework.
4. analyze the modulation of cortical homeostasis during early embryonic development and between different cell types during embryonic morphogenesis.
In conclusion, this proposal aims to understand the regulatory mechanisms that underlie cortical homeostasis in face of developmental and environmental perturbations, simultaneously allowing cells to regulate their cytoskeleton with exquisite refinement and to produce specific cell behaviors important for the cell physiology, development and morphogenesis.