Figure 3.
Local endocytosis is regulated at cellularization. (A) Cross-sections show many Amph (green) tubules (arrows) extend from incipient furrow tips (Septin; red). At 5 μm furrow length furrow canals are assembled (level of black arrowhead), and few tubules are seen. (B) Projected Z-section shows Amph (green) tubule (arrows) extending from furrow tip (septin; red; level of black arrowhead). (C) Number Amph tubules in wild-type embryos during cellularization. Each point represents one embryo with 160–180 furrows analyzed. Tubules are not detected at ≥ 5 μm furrow length. (D) Sequential planes in a Z-stack (moving deeper from left to right, 0. 5 μm step) show an Amph structure in cross-section (arrow). It appears as a circle, consistent with it being a tubule. Bars are 5 μm.