Fig. 7. Effects of altered Cdc42 activity on macrophage. (A,D,G) Stage 15 embryos stained with anti-peroxidasin antibody to label macrophages. Embryos expressing Cdc42^N17 (A) or Cdc42^V12 (D) under the control of gcm-Gal4 show a wild type distribution of macrophages. A Cdc42^V12-expressing embryo has a reduced number of macrophages but they are larger. (G) Embryos with overall reduced Cdc42 activity (Cdc42^MZ mutants) show an absence of macrophage migration along the ventral cord. (B,E,H) Transmission electron micrographs of stage 14 embryos. Macrophages expressing Cdc42^N17 (B), or Cdc42^V12 (E), or macrophages in Cdc42 mutant embryos (H) display wild-type morphology with normal membrane extensions and presence of phagosomes (arrows). Some Cdc42^V12-expressing macrophages contain two nuclei (arrowheads in E). (C,F,I) Embryos expressing Cdc42^N17 or Cdc42^V12 under the control of Coll-Gal4 line. Embryos also carried UAS-lacZ and were stained with anti-ß-Gal antibody. Each panel shows a close-up of a whole-mount stage 17 embryo, focusing on the ventral area between the epidermis and the ventral cord. (C) Cdc42^N17-expressing macrophages are evenly distributed and have a wild-type morphology. (F) Cdc42^V12-expressing macrophages have a normal distribution, but the cells do not show cytoplasmic protrusions and have a rounded morphology. (I) Wild-type embryo. Bars, 10 µm (B,E,H).