Fig. 8. Drosophila Nemo phosphorylation promotes the nuclear export of Mad. COS-7 cells were transfected with the constructs indicated and stained for the localization of Mad (green, upper panel of each pair) and with DAPI to indicate nuclei (blue, lower panel of each pair). MadS25A is primarily nuclear (A), whereas MadS25D is heavily enriched in the cytoplasm (B). Percentages indicate the number of cells displaying a primarily nuclear localization. (C,D) The localization of Mad is influenced by Tkv receptor activation. (E,F) Co-transfection of Nemo inhibits the Tkv-induced nuclear accumulation in the absence of leptomycin B (LMB) (E), but does not block nuclear retention in the presence of LMB (F).