Fig. 1. Localization of Par-1 in the Drosophila embryo and eye imaginal disc. (A-E) Embryos stained for PAR-1 protein (green) and nuclei (red). All views except B are mid-sagittal; B is of the blastoderm at the apicolateral plane. (A,B,C,D,E) Low magnification views of embryos at different stages. (A',B',C',D',E') High magnification views of the developing blastoderm and ectoderm, with the apical region oriented towards the top. (A,A') Early cellularization. (B,B') Mid-cellularization; PAR-1 is reduced apically and localized laterally, including the furrow canal (arrow). (C,C') Late cellularization. (D,D') Stage 8 gastrulating embryo showing apical and apicolateral PAR-1 in the ectoderm. Weak staining is also present in neuroblasts. (E,E') Stage 15 embryo, with higher levels present in the nervous system and midgut. (F-H) Localization of PAR-1 (green) in eye imaginal discs. (F) A low magnification view of the eye disc. The band of strong staining is the morphogenetic furrow. (G) A transverse view of three ommatidia with the apical region oriented toward the top. PAR-1 is concentrated in apical and apicolateral regions. E-cadherin (red) marks the AJ in projections of photoreceptor neurons. (H) A planar view at the apicolateral plane of disc cells. Par-1 is detected around cell membranes and in the photoreceptor AJs containing E-cadherin (red).