Fig. 5

a UCSC Genome Browser view of the zebrafish ptf1a and human PTF1A genomic landscapes showing H3K27ac ChIP-seq (black), ATAC-seq (blue) and ptf1a 4 C interactions (purple) from whole zebrafish pancreas samples (upper panel), with a zoom-in (middle panel), and H3K4me1 ChIP-seq data² (black) from human embryonic pancreatic progenitors (lower panel). Grey boxes highlight two previously validated zebrafish enhancers, zP.E1 and zP.E2 in the vicinity of the ptf1a gene. Green boxes highlight a distal enhancer in zebrafish, zP.E3, and the location of its putative human functional ortholog hP.E3. b Confocal images of zebrafish reporter stable transgenic lines Tg(zP.E3:GFP) (n = 10) and Tg(hP.E3:GFP) (n = 3), showing co-localization of GFP expression (green) with Nkx6.1 (white), a marker of pancreatic progenitors, at 48 hpf. Delta-cells of the endocrine pancreas express mCherry (red) and nuclei are labelled with DAPI (blue). Scale bar: 25 μm. c Schematic depiction of the CRISPR-Cas9 mediated 632 bp deletion (Deletion 1) of the zP.E3 enhancer. d Pancreatic progenitor domain area, defined by Nkx6.1 (white), of homozygous (−/−; n = 5), heterozygous (wt/−; n = 13) and wild type (wt/wt; n = 6) embryos for Deletion1 of zP.E3, at 48 hpf. Unpaired student’s t-test (two-tailed), p-values < 0.05 were considered significant (*p = 0.017, ***p = 0.0002). e Percentage of larvae (−/−, n = 12; wt/−, n = 14 and wt/wt, n = 12) with different pancreatic phenotypic defects (normal, mild and severe) at 9 dpf. Fisher’s exact test (two-sided), p-values < 0.05 were considered significant (***p = 0.0003). f Representative confocal images (maximum intensity projections) of the pancreatic progenitor domain (yellow dashed line) of zP.E3wt/wt (n = 6) and zP.E3−/− sibling embryos (n = 5) at 48 hpf. Nuclei are stained with DAPI. Scale bar: 25 μm. g Epifluorescence live images of representative phenotypes quantified in e). Scale bar: 250 μm. ela elastase, sst somatostatin. For d, e, source data are provided as a Source Data file.