Fig. 4. RhoA is required for phagocytosis and bead-induced CL-1 expression. (A) Anti-5 mAb-coated beads were added to cells transfected with dominant-negative mutants of Rac 1, RhoA or Cdc42 and a reporter construct of CL-1 promoter driving luciferase expression. Luciferase activity was measured 24 hours after bead addition. (B) CL-1 promoter driven luciferase activity was measured 24 hours after addition of invasin-coated beads to cells transfected with RhoAN19 or RhoAV14. Error bars represent ± s.d. of triplicates in one of two experiments. (C) Micrographs of the phagocytosis assay after 2 hours of bead addition to dominant-negative RhoA-transfected cells.