NeuroD is required for differentiation of the granule cells in the cerebellum and hippocampus.

NeuroD, a bHLH transcription factor, is implicated in differentiation of neurons and pancreatic beta cells. NeuroD-null mice die shortly after birth due to severe neonatal diabetes. To examine if there is postnatal neuronal phenotype in these mice, we rescued them from neonatal lethality by introducing a transgene encoding the mouse neuroD gene under the insulin promoter. These mice survive to adulthood but display severe neurological phenotype due to neuronal deficit in the granule layers of th

e cerebellum and hippocampus. We show here that NeuroD is required for these postnatally generated microneurons to undergo proper differentiation, the absence of which results in cell death.[less]