Floor plate descendants in the ependyma of the adult mouse Central Nervous System.

During embryonic development of the Central Nervous System (CNS), the expression of the bHLH transcription factor Nato3 (Ferd3l) is unique and restricted to the floor plate of the neural tube. In mice lacking Nato3 the floor plate cells of the spinal cord do not fully mature, whereas in the midbrain floor plate, progenitors lose some neurogenic activity, giving rise to a reduced population of dopaminergic neurons. Since the floor plate is considered to be disintegrated at the time of birth, Nato3 expression was never tested postnatally and in adult mice.

Nato3 plays an integral role in dorsoventral patterning of the spinal cord by segregating floor plate/p3 fates via Nkx2.2 suppression and Foxa2 maintenance.

During embryogenesis, the dorsal roof plate and the ventral floor plate (FP) act as organizing centers to pattern the developing neural tube. Organizer-secreted morphogens provide signals that are interpreted via the graded expression of transcription factors. These factors establish a combinatorial code, which subsequently determines the fate of neuronal progenitors along the dorsoventral axis.