Figure 5.

Alteration of Golgi unit transport toward and through RCs upon MTs depletion. (A) MTs are visualized with a αtub84-GFP or (B) a Dmn-GFP construct (green). Phalloidin (red) labels actin at the RCs and at the plasma membrane cortex. MTs converge toward RCs. Some seem to extend through it. Arrowheads point to the RC hedges (A). Scale bar, 40 μm. (C and D) MT depletion upon colchicine treatment (D) induces the redistribution of Golgi units between NCs and the oocyte as well as their clustering in big aggregates compared with untreated (C). Scale bar, 40 μm. (E–H′) Successive snapshots taken at different time intervals in colchicine-treated living egg chambers. (E–H) Entrance: in the absence of MTs, Golgi units lying at RC vicinity enter the oocyte with a straight trajectory and at a constant and slow velocity, suggesting a switch from active transport to diffusion between NC and the oocyte. (E′–F′) Exit. Unidirectional transport is abolished in absence of MTs network. Golgi units can now leave the oocyte. n, number of chambers; p, number of particles. Scale bar, 6 μm. (I–J) Fixed preparations of wt and colchicine-treated egg chambers. When the MTs network is impaired, actin baskets are not present anymore. Scale bar, 6 μm.