Fig. 4.

Rb1 increased actin polymerization through p38 MAPK and Akt activation. (A–B) Peritoneal macrophages were cultured with (A) unopsonized beads or (B) IgG-opsonized beads (IgGbead) for 20 min and followed by flow cytometry. (C) Macrophages were cultured with E.coli or IgGbead for the indicated times, and the whole cell lysates were subjected to electrophoresis in polyacrylamide gels. (D–E) Macrophages were cultured with LY294002 (LY; 10 μM) or SB203580 (SB; 10 μM) for 30 min, before exposure to Rb1 (3 μM) for 1 h and then subjected to IgGbead for 20 min. (D) The whole cell lysates were subjected to western blotting. (E) Relative fluorescent units of phalloidine to DAPI were measured by fluorescence plate reader. Each bar represents the mean ± SD (n = 5). *p < 0.05 compared to the control. ^†p < 0.05. MAPK, mitogen-activated protein kinase; PAK, p21-activated kinase; SD, standard deviation.