Gene expression programs underlying spinal commissural neuron differentiation and axon growth across the midline

ABSTRACT: Commissural neurons (C-neurons) in the embryonic spinal cord project axons across the midline and have long served as a model system for axon pathfinding. The shared transcriptional programs for axonal midline crossing and the divergent gene expression signatures that define C-neuron subtypes have remained largely elusive, as lineage-based methods for accessing these neurons are hindered by their extensive heterogeneity. Here, we combined a genetic labeling strategy with single-cell RNA sequencing and complementary methods to study gene expression in developing C-neurons. We identify molecularly distinct C-neuron subtypes that reveal stratification of this neuronal class beyond progenitor identity and birthdate. We also uncover a large-scale gene expression switch that coincides with commissural axon growth across the midline and underlies differential axonal protein expression for guidance towards and away from the midline. Our findings elucidate both shared and subtype-specific transcriptomic programs that drive C-neuron differentiation and axon midline crossing.

ORGANISM(S): Mus musculus

PROVIDER: GSE316583 | GEO | 2026/09/14

REPOSITORIES: GEO