pah1Δ has fewer lipid droplets but a similar amount of neutral lipid. (A) Abbreviated diagram showing the final steps in neutral lipid synthesis. Pah1p*, phosphorylated cytosolic Pah1p; LD, lipid droplet; TAG, triacylglycerol; StE, steryl ester. (B) BODIPY-stained ER rings (arrows). Fluorescence images of cells of the indicated strains containing the ER marker CFP-HDEL, which were cultured in minimal dextrose medium (SD) and stained with BODIPY. Note the fewer droplets in pah1Δ. Bar, 5 µm. (C) Comparison of droplet number in wild-type (WT) and pah1Δ cells. ***, P < 0.0001; droplets in cells (examining z-section series) from four independent experiments, at least 20 cells per field; SEM shown. (D) Total neutral lipid content from mass spectrometry. Means and ranges are shown from two independent experiments.