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Fig. 2. Levels of Medea in dorsal nuclei increase sharply at the onset of
gastrulation. Optical sections of wild-type (WT) embryos co-stained for Medea
(green) and with the DNA dye ToPro3 (red). Dorsal (D) and ventral (V) midline
cells from a single embryo are shown as paired images for each stage, with
Medea staining alone (top pair) and merged with DNA dye (bottom pair). (A)
Most stage 5 embryos have a subcellular distribution of Medea that is
indistinguishable between dorsal and ventral cells, but a few (B) show uniform
distribution of Medea between the nuclei and cytoplasm within a broad domain
of dorsal cells. (C) At the onset of gastrulation, all embryos show strong
nuclear accumulation of Medea within a narrow stripe of cells at the dorsal
midline.