The Lifeact-EGFP Quail: A New Avian Model For Studying Actin DynamicsIn Vivo

Here we report the generation of a transgenic Lifeact–EGFP quail line for the investigation of actin organization and dynamics during morphogenesisin vivo. This transgenic avian line allows for the high-resolution visualization of actin structures within the living embryo, from the subcellular filaments that guide cell shape to the supracellular assemblies that coordinate movements across tissues. The unique suitability of avian embryos to live imaging facilitates the investigation of previously intractable processes during embryogenesis. Using high-resolution live imaging approaches, we present the dynamic behaviours and morphologies of cellular protrusions in different tissue contexts. Furthermore, through the integration of live imaging with computational segmentation, we reveal the dynamics of cells undergoing apical constriction and the emergence of large-scale actin structures such as supracellular cables and rosettes within the neuroepithelium. These findings not only enhance our understanding of tissue morphogenesis but also demonstrate the utility of the Lifeact–EGFP transgenic quail as a new model system for livein vivoinvestigations of the actin cytoskeleton.