Fig. 3

Salivary gland architecture exhibits highly variable morphological features. Images are examples of the characteristics observed and quantified in Table 4. a DIC imaging of a female DL lobe stained with DAPI (nuclei). Two areas of non-cellular basal ECM are visible (arrows). An isolated cell is sometimes observed associated with the basal ECM (yellow arrow), but not always (white arrow). b Female DL lobe stained with DAPI and Nile Red and imaged for fluorescence with DIC. SG cells were sometimes missing, as in the region outlined and marked with asterisks. c Male SG stained with Nile Red and DAPI. Rare instances of misoriented cells (yellow arrow) were observed. Typically, cells are basally positioned and apico-basal polarity (white arrow) is directed toward the lumen/duct. In this example, the secretory cavity runs parallel to the duct (yellow arrow), and opens into an adjacent secretory cavity, not the lumen. d Four-lobed female adult SG stained with WGA (chitin, O-GlcNAc groups), Phalloidin (actin), and DAPI (nuclei). Phalloidin staining is observed along cell membranes. WGA staining highlighted duct structure. Nuclear (DAPI) and actin (phalloidin) signal and localization were similar between lateral lobes (Dii-ix). An additional lateral lobe (yellow DL in Di) is observed (Dii-v), differing from typical lateral lobes (Dvi-ix); the duct is fused (Div), but actin and nuclear position/morphology appear normal. Small DAPI bodies (see Fig. 6) are marked by gray arrows. e Male SG stained with WGA (chitin) and DAPI, imaged with DIC and fluorescence. Frequent bifurcation (two distal “lobes”), premature termination (black arrow), and occasional misdirected ducts (yellow arrow) were observed. f Nile Red- and DAPI- stained female DL lobe with small lumen (Fii, white arrows). Even without extensive lumen expansion (white arrows), DL lobe cells are cup-shaped with visible secretory cavities, surrounded by a large basal ECM territory and the basement membrane. Duct images not labeled “MIP” are single Z-slices. Scale bar lengths are: 50 microns—A, Bi, Ci, Di, Fi; 20 microns—Bii, Cii, Dii, Dvi, E