Fig. 6. Rst function is required to achieve proper Dpp signaling activity in the Drosophila pupal retina. (A,B,D,E,G,H) p-Mad staining in 31 hours APF retinas from wild-type (A,B) and rst mutant animals (D,E,G,H). (C,F,I) Anti-Armadillo staining of the retinas to visualize the cells. Abnormally high levels of p-Mad were observed in genotypically rst IPCs (E,H; compare with B). Arrows point to sensory bristles. (J-L) 42 hours APF retinas overexpressing activated Tkv (GMR>tkv^Q253D). The predominant phenotype observed (J,K, arrows point to examples of multi-layered IPCs), except for the most-anterior part of the retina which showed only minor IPC patterning defects (L, arrowheads).