7-day-old CK-B deficient and wildtype neurons were transfected with plasmid DNA encoding APP-YFP. After 24 hours cells were subjected to live imaging at 37°C and 5% CO2. Panel A shows 5 successive captures of a transfected neuron. An APP-YFP-containing vesicle, which traverses the neuron, is marked by arrows. The bar represents 10 μm. B) The average velocity of APP-YFP positive vesicles in both wildtype and CK-B deficient neurons was calculated and plotted in the diagram. For wildtype and CK-B (-/-) cells 45 vesicles and 53 vesicles were tracked, respectively. C) Maximum velocities for individual particles of wildtype and CK-B knockout cells were also plotted.