Figure 4—figure supplement 1.

(A) In the adult zebrafish, a subpopulation of HuC/D⁺ ENS neurons (green) are highlighted by Tg(SAGFF217;UAS:mmCherry), and Cherry expression (red, arrows) fills both the cell bodies and the abundant processes of expressing cells (red). The remaining proportion on HuC/D⁺ cells (green) do not express Cherry (arrowhead) (n = 12). Confocal image is a max projection of a short confocal stacks. (B) Electron microscopy image of a section from an adult Tg(her4.3:EGFP;SAGFF217;UAS:mmCherry) gut with tissue layers denoted, false coloured to depict the position of the GFP⁺ cell shown in the super resolution image shown in inset. Note the neuron and axons in this section are not Cherry⁺ neurons. Images depict a single z plane. (C) High magnification view of the boxed region, showing crenelated nuclei (arrows) and radial extensions that separate axon bundles (yellow arrowheads, asterisk denotes axon bundle), and many which contact the neuronal cell body (neuronal cell body denoted with N). The EGFP⁺ cell has a cell soma size of 79.1 µm³ and longest projection length of 9 µm. Representative images of six regions of interest scanned from two adults. Scale bars: 10 µm (A,B) and 1 µm (C).