Molecular fingerprinting delineates progenitor populations in the developing zebrafish enteric nervous system

Abstract

Background:: To understand the basis of nervous system development, we must learn how multipotent progenitors generate diverse neuronal and glial lineages. We addressed this issue in the zebrafish enteric nervous system (ENS), a complex neuronal and glial network that regulates essential intestinal functions. Little is currently known about how ENS progenitor subpopulations generate enteric neuronal and glial diversity. Results:: We identified temporally and spatially dependent progenitor subpopulations based on coexpression of three genes essential for normal ENS development: phox2bb, sox10, and ret. Our data suggest that combinatorial expression of these genes delineates three major ENS progenitor subpopulations, (1) phox2bb +/ret-/sox10-, (2) phox2bb +/ret +/sox10-, and (3) phox2bb +/ret +/sox10+, that reflect temporal progression of progenitor maturation during migration. We also found that differentiating zebrafish neurons maintain phox2bb and ret expression, and lose sox10 expression. Conclusions:: Our data show that zebrafish enteric progenitors constitute a heterogeneous population at both early and late stages of ENS development and suggest that marker gene expression is indicative of a progenitor's fate. We propose that a progenitor's expression profile reveals its developmental state: “younger” wave front progenitors express all three genes, whereas more mature progenitors behind the wave front selectively lose sox10 and/or ret expression, which may indicate developmental restriction. Developmental Dynamics 245:1081–1096, 2016. © 2016 Wiley Periodicals, Inc.