Figure 5

Early adult SG DL stained with antibodies to the secreted proteins SG6 (blue) and AAPP (red), and stained with the dyes WGA (green–O-GlcNAcylated proteins and chitin) and DAPI (white, DNA). (A) High magnification confocal slice of the DL at a plane between the apical and basal surface reveals large secretory cavities lined with WGA staining as well as occasional PACs (arrows). (B) High magnification confocal slice of the DL at a plane of the apical surface reveals large secretory cavities lined with WGA staining as well as occasional PACs (arrows). (C) A WGA-, SG6-, and AAPP-positive PAC is observed adjacent to the nucleus (arrow). Small vesicle-like buds are seen between the PAC and the apical surface/SC (A,C,D, arrowheads). (D) A smaller PAC with more vesicles between the PAC and the secretory cavity. (E) A PAC (arrow) is observed fusing to a secretory cavity. Individual channels are denoted “p”, “b”, “g”, or “r”. “G” indicates perinuclear staining that is likely to correspond to the Golgi. Scale bar lengths are given in microns.