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Figure S2. MβCD and LTB treatment of PC3 cells. (A–C) Actin (left) or CD9 (right) labeling performed with AlexaFluor488-labeled phalloidin or Atto647-conjugated SYB-1 antibodies, respectively, for each set of experiments, namely control cells (A) and MβCD- (B) or LTB (C)-treated cells. After MβCD treatment (B), the dotlike pattern corresponding to tetraspanin-enriched compartments was preserved as well as the actin network. After LTB treatment (C), the actin network was completely disrupted, whereas the dotlike CD9 pattern was still observed. Note that actin fluorescence labeling was observed in epifluorescence microscopy. (D) Distribution of ADC for CD9 molecules after MβCD treatment (left) and a sequential treatment with MβCD and LTB (right). To further support that MβCD effect on CD9 behavior was not caused by changes in membrane–cytoskeleton interactions, MβCD-treated cells were incubated with LTB. Under these conditions, the shape of the ADC values distribution was similar to that of MβCD-treated cells as well as the ADC mean value (0.07 ± 0.06 µm²/s vs. 0.08 ± 0.09 µm²/s), and the percentage of confined trajectories (34 vs. 31%) are similar to MβCD-treated cells (Table I). Bars, 10 µm.