Fig. 6. Subcellular localization of HA-FOI. (A) Deconvolution microscopy image of a Schneider S2 cell expressing HA-FOI immunolabeled with an anti-HA antibody (red) and stained with DAPI to reveal the nucleus (DNA, blue). Note that the FOI protein is localized to the plasma membrane. (B) Deconvolution microscopy image of a stage 14 embryonic gonad expressing HA-FOI in the germ cells, immunostained for a germ cell marker (anti-VASA, green) and HA-FOI (red). HA-FOI is predominantly localized to the germ cell surface. (C) Confocal image of a stage 16 embryonic gonad expressing HA-FOI in the mesoderm (expression driven by twist 24B gal4), including gonadal mesoderm, immunostained to label the gonadal mesoderm (anti-ZFH-1, red) and HA-FOI (green). Note that HA-FOI is observed surrounding each germ cell (asterisks), although the germ cells are not expressing HA-FOI in this experiment. HA-FOI partially co-localizes with DLG at the surface of gonadal mesoderm cells (inset) in a stage 16 embryo immunostained to label DLG (red), HA-FOI (green, expression driven by 24B Gal4) and germ cells (anti-vasa, blue). (D) Confocal image of a stage 15 embryo expressing HA-FOI in the trachea, immunostained to reveal the tracheal lumen (Mab 2A12, green) and HA-FOI (red). Lateral trunk branches are shown. HA-FOI appears to localize to the cell periphery and also to extensions between fusion tip cells during branch fusion (inset). In all panels shown, the HA-tag is in the N-terminal region of FOI.