Figure 1.

Birefringent gut granules are located within acidic compartments. Birefringent gut granules (B) in a wild-type 1.5-fold stage embryo colocalized with acidified, acridine orange-stained (C) compartments (white arrows). Some acidic intestinal compartments stained by acridine orange did not contain detectable birefringent material (white arrowheads). In A–C, a black arrowhead marks the anterior of the intestinal primordium. A newly hatched L1-stage larvae (D–G) contained birefringent gut granules within acidified and autofluorescent intestinal organelles. Birefringent gut granules colocalized with autofluorescent and acidic LysoTracker Red-stained compartments (white arrows). Some acidic intestinal compartments stained by LysoTracker Red colocalized with autofluorescent, but not birefringent, gut granules (white arrowheads). In D–G, the intestinal lumen is marked with a black arrow.