These panels show the localization of actin filaments (red) and nuclei (blue) during the process of border cell migration during Drosophila oogenesis. One of the major functions of the follicle cells is to produce the eggshell that will surround and protect the mature egg. The border cells are a subset of follicle cells that will contribute to the anterior-most portion of the eggshell (A, arrow). Partway through oogenesis the border cells break away from the follicle cell layer and migrate as a small group to the border between the nurse cells and the oocyte. This migration is delayed when border cells have reduced levels of a potential regulator of the actin binding protein Ena (B, *). Egg chambers shown are of a similar stage. Images taken by Lindsay Regruto '12.