Figure 6:

Sea urchin embryos treated with aPKC inhibitors do not swim and exhibit short cilia. (A–C) Dark-field videomicroscopy images taken from time-lapse sequences of late gastrulas control (A) or treated with the PKC inhibitors GF109203X, 10 μM (B) and Gö 6976, 20 μM (C). White arrows indicate the presence (A, C) or the absence (B) of the apical tuft at the animal pole. Yellow arrowheads and yellow arrows indicate the archenteron and the forming spicules, respectively. (D–I) Confocal surface views of gastrula-stage embryos either (D–F) untreated or (G–I) after treatment with the myristoylated aPKC pseudosubstrate inhibitor. Fixed embryos were labeled for tubulin (D, G) or aPKC (E, F, H, I). F and I are higher-magnification views of the regions boxed in E and H.