Figure 4.

Overexpression of β-spectrin in the larval fat body altered the surface mCD8GFP pattern and eliminated the population of small, cortical lipid droplets. UAS-β-Spec⁹⁵ expression in fat body was driven by Cg-Gal4. Overexpression resulted in a dramatic increase of β-spectrin antibody staining at the ecto domain (G) compared to wild type (C). There was also an increase in mCD8-GFP intensity, making it necessary to lower the photomultiplier tube (PMT) setting during image capture (E and F) relative to that for controls (A and B). By lowering the PMT it was possible to see loss of the foamy pattern, which was replaced by a speckled pattern, similar to what was seen with β-spectrin knockdown (Figure 1). The pattern of small, cortical lipid droplets (1–5 μm) detected by DIC microscopy in controls (D) was also largely eliminated by β overexpression (H). Bars, E, 50 µm; H, 10 µm.