Figure 1.

Rab7b in migrating cells. (A) A confluent monolayer of HeLa cells that had been transfected with GFP-Rab7b was scratched with a pipette tip and fixed after 2 hours. Cells were immunostained with an antibody against giantin followed by Alexa-647 (blue). Actin was labeled with Rhodamine-conjugated phalloidin (red). Scale bar 10 μm. Magnifications of the boxed area are shown in the insets. Rab7b-positive endosomes are visible along actin filaments. (B) Model illustrating Rab7b's intracellular roles. Rab7b localizes to late endosomes (LE) and TGN/Golgi and regulates the transport between these compartments. Rab7b interacts directly with the actin motor myosin II. This interaction is important for Rab7b dynamics, but also for actin cytoskeleton remodelling and thereby for cell migration.