Tissue topography steers migrating Drosophila border cells

Cells and the path of least resistance For processes encompassing proper embryonic development, adult homeostasis, tumor cell dissemination, and immunity, certain cells must translocate from their site of origin. Migrating cells navigate physical features of their microenvironment; however, the in vivo importance of tissue topography for pathfinding is mostly unknown. Studying fruit flies, Dai et al. used border cells within the ovarian egg chamber to study path selection. Live imaging, genetics, mathematical modeling, and simulations showed that tissue microtopography provides an energetically favorable path of least resistance, whereas chemoattractants supply orthogonal guidance information and cell-cell adhesion contributes traction. The results provide insight into how cells integrate and prioritize topographical, adhesive, and chemoattractant cues to choose one path among many. Science , this issue p. 987