Coordinated Regulation of Niche and Stem Cell Precursors by Hormonal Signaling
Figure 2
Ecdysone receptors repress precocious niche formation.
(A, B) Terminal filaments of wild-type ML3 ovaries are labeled either by hh-lacZ (A, green) or anti-En (B, magenta). Few TF cells which are unorganized, or organized into short filaments, can be seen. Germ cells are marked by round fusomes (A, 1B1 antibody, magenta) or by anti-Vasa (B, green). (C, D) In EcR-RNAi (C) or usp-RNAi (D) ML3 ovaries, more TF cells and more organized filaments can be seen (anti-En, magenta, arrows). Germ cells are labeled by anti-Vasa (green). (E–I) hh-lacZ (green) marks all TF and cap cells. (E) In WT LL3 ovaries TF cells are distinguished by hh-lacZ staining and oval-shaped nuclei. LaminC (red) is only apparent in older TF cells, at the anterior of each TF stack. Cap cells (arrowheads) are at the posterior base of TF, have rounder nuclei, and do not yet stain with anti-laminC. (F) Anti-Tj (magenta) labels ICs. Cap cells that form at the base of TFs are co-stained with hh-LacZ and anti-Tj (inset, arrowheads). (G) EcR-RNAi ML3 ovaries. Unlike wild-type, Cap cells appear already at ML3 (arrowheads). (H, I) Somatic cells and fusomes are labeled by 1B1 (magenta). (H) TFs are regularly spaced in the anterior half of the wild-type ovary. (I) In EcR-RNAi LL3 ovaries, TFs are mis-positioned, with fewer cells between stacks. Bars in (A), (for A–D), in E (for E, G), and in H (for F, H, I) are 10 µm.