Temporal plasticity of apical progenitors in the developing mouse neocortex.

Area of Science:

• Developmental Neuroscience
• Cell Biology
• Neurobiology

Background:

• The neocortex develops from apical progenitors in the ventricular zone.
• Progenitors generate neurons sequentially, from deep to superficial layers.
• The temporal plasticity and fate restriction of individual progenitor types remain unclear.

Purpose of the Study:

• To investigate the temporal plasticity of apical and intermediate progenitors during neocortical development.
• To determine if progenitor fate progression implies irreversible fate restriction.

Main Methods:

• Isolation of apical and intermediate progenitors.
• Fate-mapping of neuronal progeny using heterochronic transplantation into younger embryos.
• Analysis of molecular, electrophysiological, and neurogenic states.

Main Results:

• Apical progenitors exhibit temporal plasticity, reverting to earlier states when exposed to a younger environment via Wnt signaling.
• Intermediate progenitors are committed and lack retrograde fate plasticity.
• A diversity in temporal plasticity exists among neocortical progenitor subtypes.

Conclusions:

• Neocortical progenitor cell fate is not strictly linear; some cells can reverse developmental progression.
• Apical progenitors are temporally plastic, while intermediate progenitors are fate-restricted.
• This plasticity offers insights into the dynamic regulation of cell-fate determination in the developing brain.