Article

Preservation of positional identity in fetus-derived neural stem (NS) cells from different mouse central nervous system compartments.

Department of Pharmacological Sciences and Center for Stem Cell Research, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy.
Cellular and Molecular Life Sciences CMLS (impact factor: 6.57). 10/2010; 68(10):1769-83. DOI:10.1007/s00018-010-0548-7 pp.1769-83
Source: PubMed

ABSTRACT Neural stem (NS) cells are a self-renewing population of symmetrically dividing multipotent radial glia-like stem cells, characterized by homogeneous expansion in monolayer. Here we report that fetal NS cells isolated from different regions of the developing mouse nervous system behave in a similar manner with respect to self-renewal and neuropotency, but exhibit distinct positional identities. For example, NS cells from the neocortex maintain the expression of anterior transcription factors, including Otx2 and Foxg1, while Hoxb4 and Hoxb9 are uniquely found in spinal cord-derived NS cells. This molecular signature was stable for over 20 passages and was strictly linked to the developmental stage of the donor, because only NS cells derived from E14.5 cortex, and not those derived from E12.5 cortex, carried a consistent transcription factor profile. We also showed that traits of this positional code are maintained during neuronal differentiation, leading to the generation of electrophysiologically active neurons, even if they do not acquire a complete neurochemical identity.

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Keywords

anterior transcription factors
 
complete neurochemical identity
 
consistent transcription factor profile
 
developing mouse nervous system
 
different regions
 
electrophysiologically active neurons
 
exhibit distinct positional identities
 
fetal NS cells
 
homogeneous expansion
 
Hoxb9
 
monolayer
 
multipotent radial glia-like
 
neuronal differentiation
 
NS
 
NS cells
 
self-renewal
 
spinal cord-derived NS cells
 

Marco Onorati