Figure 5

Pvr controls cell growth in a variety of cell lines and in Drosophila hemocytes. (a) F-actin staining of Drosophila S2 and ML-DmBG3-c2 (neuronal) cells treated with dsRNA to LacZ or Pvr reveals a reduction in cell size in Pvr RNAi cells relative to control. (b) Pvr and Ras1 dominant negative constructs were expressed in larval hemocytes in vivo using the Cg-Gal4 driver. Hemocytes were extracted, allowed to adhere to conconavalin A and then fixed and stained for F-actin. Cell area was measured from images of hemocytes (see Materials and methods). Both Pvr and Ras1 DN constructs caused a significant reduction in hemocyte cell area relative to wild-type (WT). (c) Driving expression of Pvr RNAi constructs in hemocytes using either Cg-Gal4 or Hml-Gal4 causes a significant decrease in cell size relative to control (driver or hairpin only) cells. Cells were stained for F-actin. Control and experimental images in (b, c) were taken at the same magnification. Error bars indicate the standard error of the mean.