Figure 1. Introduction to the stress fibers (SFs) in collectively migrating follicle cells.

(A) Composite images of an egg chamber (pseudocolored), transverse section above and 3D cutaway view below. Curved arrow shows the rotational migration of the follicle cells as they crawl along the basement membrane extracellular matrix (ECM) (drawn as a line in upper image, from a confocal section of Collagen-IV-GFP in lower image). (B) Image of the basal surface of the follicular epithelium. Each cell has a leading-edge protrusion (yellow) and a parallel array of SFs (orange) oriented in the direction of migration. Experiments performed at stage 7. Gray arrows show migration direction. Scale bars 10 µm.