Msn appears to promote detachment of the cell’s trailing edge. (A) Control and msn-RNAi flipout clones (GFP) show that Msn depletion causes cell stretching, often forming a “tail” at one end. (B and C) Stills from two time-lapse movies of egg chambers with clones of cells expressing msn-RNAi and mCD8-GFP (Videos 5 and 6), which show that the “tails” form at the trailing edge of the migrating msn-RNAi cells (B), and can retract as the cells move forward (C). (D) Maximum projection of the basal surface in an egg chamber expressing Talin-GFP with msn-RNAi flipout clones (RFP). The migration direction for all panels is down (arrow). (E) Schematic for Msn’s role in follicle cell migration and planar polarity.