Figure 5

In situ hybridization. Expression of survivin at advanced stages of gut regeneration (days 12 - 21 after evisceration). (A) Section through the posterior rudiment at its attachment to the cloaca on day 12. (B) High magnification view of the boxed area on (A). (C) Section through the posterior regenerate at a more anterior level relative to (A). (D) and (E) show high magnification views of the boxed areas on (C), representing the mesenterial attachment and the digestive epithelium, respectively. (F) The wall of the esophageal stump on day 12. (G) and (H) Sequential sections trough the tip of the blindly ended anterior rudiment on day 12. (I) and (J) The wall of the posterior portion of the regenerated digestive tube on day 21, showing scatted labeled cells in the luminal (digestive) epithelium (I) and no labeling in the mesothelium (J). (K) The wall of the anterior region of the regenerated gut on day 21, showing expression of survivin in the mesothelium. de - digestive (luminal) epithelium; ct - connective tissue layer; m - mesothelium. Scale bars = 100 μm in (A), (D), (G), (H); 50 μm in (B), (E), (I), and (J); 200 μm in (C); 25 μm in (F) and (K).