FIGURE 3.
Dorsal activation is triggered by extracellular stimuli. A, dorsal intracellular distribution in droncΔA8 mosaic clones. RFP negative cells are homozygous droncΔA8 mutant cells. Nuclear RFP (red) and Dorsal protein (green) were examined by immunohistochemical staining. The larval genotype was hs-Flp;;His2Av-RFP,FRT80B/droncΔA8,FRT80B. Scale bar, 50 μm. B–E, immunohistochemistry staining of fat body explants incubated with Ringer's solution (B), hemolymph from wild-type (w1118, C), droncΔA8 mutants (D), or droncΔA8 spzrm7 double mutants (E). The distribution of DNA (magenta), Dorsal (green), and F-actin (yellow) is shown as maximal projection confocal images. An image overlay illustrates Dorsal nuclear translocation. Scale bar, 20 μm. F, classification of Dorsal distribution in fat body explants, based on Dorsal nuclear staining patterns. Scale bar, 20 μm. G, for each culture condition, the percentage of cells associated with each Dorsal staining pattern was calculated. The total cell number counted for each treatment is indicated as N. N was normalized to 100%.