Fig. 3.

Latrunculin A inhibited insulin-induced caveolin-1 and IR/IGF-IR trafficking to the plasma membrane. After serum starvation for 24 h, cells were pretreated with 25 nm latrunculin A (Lat) for 30 min followed or not by insulin treatment for 30 min. Plasma membrane sheets were prepared followed by double staining for IGF-IR (red), caveolin-1 (green), IR (red), and ICAM (used as a control) (green). A, Representative confocal images of single optical sections from three independent experiments. For EBM, cells were incubated in basal medium only without insulin. B–E, Quantification of changes in the fluorescence intensity of IGF-IR, caveolin-1, IR, and ICAM, respectively. *, P < 0.05 compared with remaining groups. NS, Not statistically significant.