The GATA transcription factor Serpent is required for amplification of adult fat body precursors.

(A) Adult fat body precursors (OK6-GAL4-driven GFP, green) from an abdomen dissected 72 h APF and stained with anti-Srp antibody (magenta). Nuclei stained with DAPI (cyan). (B) Adult abdomens from a wild-type fly and flies in which srp was knocked down with 3 different RNAi transgenes under OK6-GAL4 control (OK6>srpⁱ). Controls knocking down genes white (OK6>wⁱ) and yellow (OK6>yⁱ) are shown as well. Abdomens were dissected 2 days after eclosion and mounted flat after staining with DAPI (nuclei, blue) and BODIPY (neutral lipids, green). (C) Quantification of adult fat body reduction upon srp knock down. Graph represents the coverage of adult fat body measured in images like those in (B) in at least 5 individuals per genotype, with the height of the bar indicating mean value. Significance of comparisons with the wild type in unpaired t tests reported as follows: n.s.: p > 0.05; ****: p < 0.0001. (D) Adult fat body precursors (OK6-GAL4-driven GFP, white) imaged in vivo in the abdomen (ventral view) of wild-type (top) and OK6>srpⁱ (bottom) pupae at 30 (left) and 36 (right) h APF. Images are maximum intensity projections of 65 confocal sections. (E) Graph representing number of adult fat body precursors at 30 and 36 h APF in 3 wild-type and 3 OK6>srpⁱ animals. Cells were counted in images like those in (D). The data underlying the graphs in the figure can be found in S1 Data.