Fig. 8. Head regeneration is altered in cnox-2 RNAi hydra. (A) Delay in head regeneration after 5x (n=12) and 9x (n=15) cnox-2 dsRNA exposures. (B-J) Cellular analyses of head-regenerating hydra amputated after 5x exposures to dsRNAs. (B,C) Decrease in the number of cnox-2⁺ cells in head-regenerating tips (B) and body column (C) of lower halves at 30 and 48 hpa. (D-H) cnox-2 expression in head-regenerating hydra exposed to Kazal1 (D,F) or cnox-2 (E,G,H) dsRNAs. Right panels: enlarged views of tips (arrows), TBs (arrowheads) and body column (D,E). Note the small size and the delayed regeneration of animals shown in G,H when compared with F. (I,J) Anti-ß-tubulin staining of head-regenerating tips at 39 hpa in hydra exposed to cnox-2 (I) or control (J) dsRNAs. Results depicted in panels A,B-H,I,J correspond to three independent experiments. Scale bars: 200 µm in D-H; 100 µm in I,J.