Article

Wnt signaling and its downstream target N-myc regulate basal progenitors in the developing neocortex.

Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
Development (impact factor: 6.6). 04/2010; 137(7):1035-44. DOI:10.1242/dev.046417 pp.1035-44
Source: PubMed

ABSTRACT Basal progenitors (also called non-surface dividing or intermediate progenitors) have been proposed to regulate the number of neurons during neocortical development through expanding cells committed to a neuronal fate, although the signals that govern this population have remained largely unknown. Here, we show that N-myc mediates the functions of Wnt signaling in promoting neuronal fate commitment and proliferation of neural precursor cells in vitro. Wnt signaling and N-myc also contribute to the production of basal progenitors in vivo. Expression of a stabilized form of beta-catenin, a component of the Wnt signaling pathway, or of N-myc increased the numbers of neocortical basal progenitors, whereas conditional deletion of the N-myc gene reduced these and, as a likely consequence, the number of neocortical neurons. These results reveal that Wnt signaling via N-myc is crucial for the control of neuron number in the developing neocortex.

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Keywords

basal progenitors
 
beta-catenin
 
developing neocortex
 
intermediate progenitors
 
N-myc gene
 
N-myc mediates
 
neocortical basal progenitors
 
neocortical development
 
neocortical neurons
 
neural precursor cells
 
neuron number
 
neuronal fate
 
neuronal fate commitment
 
stabilized form
 
unknown
 
vitro
 
vivo
 
Wnt signaling
 
Wnt signaling pathway