Collectively migrating border cells integrate physical, chemical and adhesive cues to choose a path

Border cell migration in the Drosophila ovary is a relatively simple model for the study of collective, cooperative, cell contact-dependent migration in vivo, which is amenable to live imaging, genetic, and optogenetic approaches. Decades of work have revealed the secreted signals that govern which 6 of the 850 epithelial cells acquire the ability to migrate, when during development they do so, and where they go. In addition to biochemical signals, moving cells also sense and respond to physical features of the microenvironment; however, the significance of tissue topography remains relatively unexplored, particularly in vivo.