Ascl1 controls late neuronal specification of central canal neurons

GUILLERMO LANUZA; DANIELA DI BELLA; ABEL CARCAGNO

Buenos Aires

Congreso; 2nd Falan congress 2016; 2016

The production of the functional nervous system consists of an integrated series of steps that allows the generation of diverse neuronal and glial cell types at their correct positions and appropriate number. During development, the acquisition of specific neuronal identities is initiated by external signals in positional coordinates, triggering transcriptional networks in progenitors and newborn neurons to specify distinct fates. This work focuses on the specification of Cerebrospinal Fluid Contacting Neurons (CSF-cN). These neurons are widely conserved in chordates, have a unique morphology, are located at the interface between the central nervous system and the CSF and are generated from late ventral progenitors during advanced developmental stages simultaneously with glial cells. The genetic regulation of this neurogenic late event in the ventral spinal cord is unknown. Through lineage tracing experiments and gene expression analysis in genetically modified mice we found that: I) Ascl1 is expressed in ventral late progenitors and is specifically required for the proper development of CSF-cNs in ammniotes, II) Ascl1 controls the start of the differentiation of CSF-cNs specifically in advanced stages of development, and III) in the absence of Ascl1, progenitors that normally generate CSF-cNs differentiate into ependymal cells surrounding the central canal, indicating that Ascl1 confers neurogenic potential to late ventral progenitors in the spinal cord.