From protein localization patterns to understanding how epithelial cells move and divide

Epithelial tissues form cohesive and selective barriers that compartmentalize animal life. While epithelia display a well defined apical-basal architecture, epithelial cells must undergo dramatic cell shape changes to accommodate tissue morphogenesis, migration and cell division. But how do they coordinate cytoskeleton remodelling with intercellular adhesion and polarity to achieve such cell shape plasticity? In this seminar, I will discuss how spatial and temporal regulation of Rho family GTPases governs two key epithelial behaviours — cell division and collective migration. By combining systematic RhoGAP/GEF family-wide GFP localization screens with quantitative imaging analysis in Drosophila and mammalian models, we mapped the distribution of these major families of cytoskeletal regulators and uncovered how precise control of RhoGTPase inhibitors (RhoGAPs) reshapes the mitotic cortex and restricts contractility to fine tune collective movement. These findings advance our understanding of how epithelial tissues preserve their function while dynamically adapting their architecture — a balance essential for animal development and homeostasis.