Fig. 5. Drm and Lin antagonize each other in vivo. Whole-mount embryos were stained with anti-Crb (A-D) or anti-En (E,F), hybridized in situ with probe for upd (G,H) or hh (I,J), or fixed and sectioned transversely (G,H). Ectopic expression of Drm throughout the hindgut with the byn-GAL4 driver produces a lin-like phenotype as observed by morphology of the hindgut (A; compare Fig. 1C), by hindgut epithelial cell shape and absence of boundary cell rows (C; compare Fig. 1G), by the lack of expression of En in the large intestine (E, white arrowhead; compare Fig. 1K), and by the posterior expansion of upd and hh from the small intestine (G and I, wide arrowheads; compare Fig. 1O and 1S). Ectopic expression of Lin throughout the hindgut using the byn-GAL4 driver produces a drm-like phenotype as observed by the morphology of the hindgut (B; compare Fig. 1B), hindgut epithelial cell shape and duplication of boundary cell rows (D, four arrows, compare with Fig. 1F), the expression of En in the dorsal large intestine (F, black arrowhead; compare Fig. 1J), the absence of upd expression in the small intestine (H, white arrowhead; compare Fig. 1N), and the expression pattern of hh (J, black arrowheads; compare Fig. 1R).