Figure 6.

Leading Edge membrane activity requires Integrin function. The dynamic activity of the leading edge of migrating CBs was monitored in living embryos, labeling membrane actin with dMef-GAL4 regulated UAS-moesin-mCherry, while marking the CBs with tup-F4-GFP. In early stage 16, wildtype CBs of segments 6-8 are 20 microns apart, and extend highly dynamic lamelipodial and filopodial processes to contact their contralateral partners (arrows in A). Although zygotic mutants of mys¹ generate similar cell processes (arrows in B), most of the leading edge is quiescent (asterisks), and medial migration is slower. Images are taken at 2 minute intervals; the dorsal midline at t = 0 is marked with a dotted line. Scale: 25 microns