Extended Data Fig. 2: Amino acid deprivation enhances the expression of CNMa in enterocytes, but not in intestinal stem cells, enteroblasts or enteroendocrine cells.
From: Response of the microbiome–gut–brain axis in Drosophila to amino acid deficit
a, Normalized CNMa mRNA expression levels measured by qPCR in flies that were fed isocaloric diets containing varying amounts of dietary yeast for 5–6 days (n = 5). b, c, CNMa promoter activity in the gut of CNMa-GAL4>UAS-GFP flies that were fed an isocaloric diet containing 2% (low-amino-acid diet) versus 10% (high-amino-acid diet) of yeast for 7 days. Representative confocal images of the whole gut (b) and quantifications of the GFP fluorescence in the R2 segment of the anterior midgut (c) are shown. d, Representative confocal images showing enterocytes in the anterior R2 midgut that express CNMa. Intestinal stem cells (ISCs) and enteroblasts (EBs) were respectively marked by β-galactose (β-gal) staining of the gut in flies carrying Delta-lacZ (red), CNMa-Gal4 and UAS-GFP (green) (top left), and in flies bearing Su(H)-lacZ (red), CNMa-Gal4 and UAS-GFP (green) (top middle). Enteroendocrine cells (EEs) are labelled by anti-prospero antibody staining (red) (top right), whereas enterocytes (ECs) are identified on the basis of their large polyploidy nuclei as revealed by DAPI staining (blue). In all cases, CNMa expression was visualized by GFP (green). A schematic representation of different intestinal cell types is shown. e, f, Representative confocal images of enterocytes in the R2 (e) and R4 (f) midgut regions of a fly carrying NP1-Gal4 (enterocyte-specific driver) and UAS-CD8-GFP co-labelled with anti-GFP (green) and anti-CNMa (red) antibodies. Nuclei are stained with DAPI (blue). Scale bars, 200 μm (b); 50 μm (c); 10 μm (d–f). Single-plane images are shown. Representative images are selected from at least 20 independent samples collected in each experiment. Data are mean ± s.e.m. P values are indicated; one-way ANOVA with Tukey’s post-hoc test in a; unpaired two-tailed t-test in c. Sample sizes and statistical analyses are shown in Supplementary Table 1.
