Fig. 5. FasII and ATP are localised to the lateral cell surface and do not affect apical membrane growth. (A,B) Confocal longitudinal sections of the DT of wild-type embryos labelled with antibodies against FasII (A) and ATP (B) show that both proteins localise to the lateral cell surface. (C,D) The expression and localization of FasII and ATP are not affected in grh mutants. (E,H) Confocal cross sections of the DT of wild-type (E,F) and Atp mutant (G,H) embryos labelled with antibodies against DE-cad (red; E,G) and Nrx (green; F,H). The lateral localization of Nrx is diffuse in the Atp mutants. (I) Electron micrograph revealing a partial cross section of the DT in an Atp mutant embryo at late stage 16. No excessive growth of the apical membrane can be seen in the Atp mutants, and the AJs appear correctly localised near the lumenal surface. Scale bar: A-D, 10 µm; E-H, 5 µm; I, 0.5 µm