Data and code from: Evidence for chronological diversification of spinal neuron subtypes by a shared sequence of transcription factors

The mechanisms underlying the generation of the immense diversity of
neuronal cell types remain a fundamental question of developmental
biology. In the spinal cord, different “cardinal classes” of neurons that
share a common molecular identity are produced from spatially segregated
progenitor domains. Within many such classes, a stereotyped sequence of
divergent neuronal types of related function is generated over time,
raising the question of the molecular mechanisms that control this
process. Here, we show that the successive expression of mouse
transcription factors Onecut2, Pou2f2, and Pou3f1 within the cardinal
classes giving rise to motor and sensory circuits, correlates with the
emergence of sequentially generated subpopulations of neurons within those
domains. We demonstrate that the genetic loss of Pou2f2 results in
impaired development of two early-born motor neuron columns and
re-specification of anterolateral system projection neurons as a
later-born subset. Similarly, we show that Pou3f1 expression is required
for the normal development of later-born subsets of motor neurons and
anterolateral system projection neurons. Together, our observations
provide functional evidence that horologic diversification of output
neurons of spinal motor and sensory circuits are driven by a conserved
sequential order of expression of transcription factors.