Figure 1

Dynamin-dependent endocytosis of ricinB:QDs into HeLa cells. Expression of the dominant-negative dynamin mutant was induced by removing tetracycline (B, -tet for 2 days), whereas control cells were grown in presence of tetracycline. All the cells were incubated with ricinB:QDs (100 nM: 20 nM) for various times at 37°C before fixation and fluorescent antibody labeling against EEA1 (green) and CD63 (blue), respectively. A/B: Internalization of ricinB:QDs into the HeLa, DynK44A cell line for 20 min, 30 min and 90 min. C: The kinetics of colocalization of ricinB:QDs and the endosomal markers EEA1(blue) and CD63 (red) in control cells (+tet) and in the mutant dynamin cells (−tet, dotted line), respectively. Quantification of the extent of colocalization between ricinB:QDs and EEA1 or CD63 (at each time point presented as percentage of cells displaying > 20% of total ricinB:QD pixels colocalizing with EEA1 and CD63, n = 30 cells pr. time point)