Figure 3.

Asymmetric segregation of Numb deletion constructs in RNA injection experiments. Stage 4 Drosophila embryos were injected with capped mRNA generated from Numb deletion constructs, aged to stage 9, then fixed and stained with an anti-Numb antibody (green) and propidium-iodide (DNA, red). Optical cross sections (apical up, basal down) through the procephalic neurogenic region of stage 9 embryos are shown. Numb-myc (A), Numb-Δ2 (D), Numb-Δ3 (E), Numb-Δ4 (F), Numb-ΔPTB (G), and Numb-Δmyr (H) are localized to the cell membrane and segregate normally into the basal daughter cell (arrow), whereas Numb-ΔN (B) and Numb-Δ1 (C) are localized in the cytoplasm and segregate equally into both daughter cells.