De novo enteric neurogenesis in post-embryonic zebrafish from Schwann cell precursors rather than resident cell types

Abstract

The enteric nervous system is essential for normal gastrointestinal function, but evidence regarding postnatal enteric neurogenesis is conflicting. Using zebrafish as a model, we explored the origin of enteric neurons that arise in post-embryonic life in normal development and injury, and tested effects of the 5-HT4 receptor agonist, prucalopride. To assess enteric neurogenesis, all enteric neurons were photoconverted prior to time-lapse imaging to detect emergence of new neurons. Injury was modeled by two-photon laser ablation of enteric neurons. Lineage tracing was performed with neural tube injections of lipophilic dye and with an inducible Sox10-Cre line. Lastly, we tested prucaloprides effect on post-embryonic enteric neurogenesis. The post-embryonic zebrafish intestine appears to lack resident neurogenic precursors and enteric glia. However, enteric neurogenesis persists post-embryonically during development and after injury. New enteric neurons arise from trunk neural crest-derived Schwann cell precursors. Prucalopride increases enteric neurogenesis in normal development and after injury if exposure occurs prior to injury. Enteric neurogenesis persists in the post-embryonic period in both normal development and injury, appears to arise from gut-extrinsic Schwann cell precursors, and is promoted by prucalopride. SUMMARY STATEMENTTrunk crest-derived enteric neurogenesis is poorly understood. We find post-embryonic zebrafish lack resident neuronal precursors yet enteric neurogenesis from trunk crest-derived precursors occurs in development, injury, and is promoted by prucalopride.