Together at last: bHLH and LIM-HD regulators cooperate to specify motor neurons.

ABSTRACT

bHLH and LIM-HD transcription factors were originally thought to act at different stages of neurogenesis bHLHs as neuronal "inducers" and LIM-HDs as postmitotic subtype determinants. These distinctions are becoming blurred, and a current study by Lee and Pfaff in this issue of Neuron shows that interaction between these factors functions to synchronize neurogenesis with neuronal cell type specification.