Fig. 1.

The microbiota promotes intestinal epithelium secretory cell fates through the Notch ligand DeltaD. (A) Representative image of cross-section stained with 2F11 antibody (e.g. black arrows). (B) Number of 2F11-positive secretory cells in CV and GF larvae; n=16. (C) Representative image of mucus-containing vacuole of goblet cells stained with Alcian Blue (black arrows). (D) Counts of Alcian Blue-positive goblet cells in CV and GF larvae; n=18 (CV), 14 (GF). (E) Representative cross-section of Tg(nkx2.2a:mEGFP) larva expressing GFP in (EECs (white arrow). (F) Number of GFP-positive EECs in GF and CV Tg(nkx2.2a:mEGFP) larvae; n=6 (CV), 9 (GF). (G) Schematic of larval zebrafish and larvae intestine. Enteroendocrine and goblet secretory cells are indicated in their normal intestinal locations. The transgene vdrb is expressed through the entire intestine whereas ifabp is expressed only in the bulb. Labeled bars by the isolated intestine schematic indicate the bulb and distal intestine regions scored for 2F11 and Alcian Blue, respectively. (H) Number of Alcian Blue-positive goblet cells in CV and GF WT and deltaD^−/− larvae; n=15 (WT), 12 (CV deltaD^−/−), 13 (GF deltaD^−/−). *P<0.05, Student's t-test. Letters denote P<0.05, ANOVA followed by Tukey's post-hoc test. Each box represents the first to third quartiles, center bar the median, and whiskers the maximum and minimum of each dataset.