Prospective identification of functionally distinct stem cells and neurosphere-initiating cells in adult mouse forebrain
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, United States
- Baylor College of Medicine, United States
- University of Texas Southwestern Medical Center, United States
Abstract
Neurosphere formation is commonly used as a surrogate for neural stem cell (NSC) function but the relationship between neurosphere-initiating cells (NICs) and NSCs remains unclear. We prospectively identified, and isolated by flow cytometry, adult mouse lateral ventricle subventricular zone (SVZ) NICs as GlastmidEGFRhighPlexinB2highCD24-/lowO4/PSA-NCAM-/lowTer119/CD45- (GEPCOT) cells. They were highly mitotic and short-lived in vivo based on fate-mapping with Ascl1CreERT2 and Dlx1CreERT2. In contrast, pre-GEPCOT cells were quiescent, expressed higher Glast, and lower EGFR and PlexinB2. Pre-GEPCOT cells could not form neurospheres but expressed the stem cell markers Slc1a3-CreERT, GFAP-CreERT2, Sox2CreERT2, and Gli1CreERT2 and were long-lived in vivo. While GEPCOT NICs were ablated by temozolomide, pre-GEPCOT cells survived and repopulated the SVZ. Conditional deletion of the Bmi-1 polycomb protein depleted pre-GEPCOT and GEPCOT cells, though pre-GEPCOT cells were more dependent upon Bmi-1 for Cdkn2a (p16Ink4a) repression. Our data distinguish quiescent NSCs from NICs and make it possible to study their properties in vivo.
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Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (protocol# 2011-0104) of the University of Texas Southwestern Medical Center. Every effort was made to minimize suffering.
Reviewing Editor
- Freda Miller, The Hospital for Sick Children Research Institute, University of Toronto, Canada
Publication history
- Received: February 27, 2014
- Accepted: May 4, 2014
- Accepted Manuscript published: May 7, 2014 (version 1)
- Version of Record published: June 3, 2014 (version 2)
Copyright
© 2014, Mich et al.
This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
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Prospective identification of functionally distinct stem cells and neurosphere-initiating cells in adult mouse forebrain
eLife 3:e02669.
https://doi.org/10.7554/eLife.02669
Further reading
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