Fig. 5.

Depletion of Aip1 alters the dynamics of the perijunctional actin cytoskeleton. A and B: control and Aip1-depleted SK-CO15 cell monolayers were subjected to a G-actin incorporation assay to evaluate actin polymerization on day 4 posttransfection. Representative images (A) and quantification of incorporated G-actin intensity (B) are shown. C and D: to measure F-actin stability, the cells were incubated for 2 h with either vehicle or Latrunculin B (Lat B) (2 μM). Cells were fixed and labeled for F-actin and ZO-1. Representative images (C) and quantification of the junctional length (D) are shown. Arrows indicate replacement of the circumferential F-actin belt by F-actin puncta and TJ disassembly in Lat B-treated cells. Data are presented as means ± SE (n = 3); *P < 0.05, ***P < 0.0005. Scale bar = 20 μm.