Figure 2

Ipiwi1 mRNA expression (A-C) and protein localization (D-G) and BrdU/ ipiwi1 (H) double labelling in I. pulchra. (A) Whole mount ipiwi1 in situ hybridization of an adult specimen. (B) Detail of developing eggs (de) and testes (t). (C) Dorsal focal plane showing ipiwi1 mRNA expressed in neoblasts (open arrowheads). (D, E) Confocal projections of Ipiwi1 protein localisation in testes and developing eggs (D) and in neoblasts (nb) (E). (F) Detail of the anterior region of (E) demonstrating Ipiwi1 positive cells (open arrowheads). (G) Detail of the posterior region of (D) demonstrating Ipiwi1 positive cells (open arrowheads). (H) Double staining of stem cells in S-phase (green) and ipiwi1 positive cells (red). Confocal projection (1,02 μm) shows the presence of BrdU-only labelled cells (green arrows), ipiwi1-only labelled cells (red arrows) as well as BrdU/piwi double labelled stem cells (yellow arrows). In all figures, anterior is to the top. Scale bars (A, D, E) 100 μm; (B, C, F-H) 50 μm.