Activation of a neural stem cell transcriptional program in parenchymal astrocytes
- Stanford University, United States
- Karolinska Institutet, Sweden
- Francis Crick Institute, United Kingdom
- Karolinska Institute, Sweden
Abstract
Adult neural stem cells, located in discrete brain regions, generate new neurons throughout life. These stem cells are specialized astrocytes, but astrocytes in other brain regions do not generate neurons under physiological conditions. After stroke, however, striatal astrocytes undergo neurogenesis in mice, triggered by decreased Notch signaling. We used single-cell RNA sequencing to characterize neurogenesis by Notch-depleted striatal astrocytes in vivo. Striatal astrocytes were located upstream of neural stem cells in the neuronal lineage. As astrocytes initiated neurogenesis, they became transcriptionally very similar to subventricular zone stem cells, progressing through a near-identical neurogenic program. Surprisingly, in the non-neurogenic cortex, Notch-depleted astrocytes also initiated neurogenesis. Yet, these cortical astrocytes, and many striatal ones, stalled before entering transit-amplifying divisions. Infusion of epidermal growth factor enabled stalled striatal astrocytes to resume neurogenesis. We conclude that parenchymal astrocytes are latent neural stem cells and that targeted interventions can guide them through their neuronal differentiation.
Data availability
The Cx30-CreER dataset (fastq files and processed expression matrix) has been deposited in ArrayExpress (accession E-MTAB-9268). The AAV-Cre dataset has been deposited in the Gene Expression Omnibus (GEO; accession GSE153916).SmartSeq2 dataset (ArrayExpress)http://www.ebi.ac.uk/arrayexpress/help/how_to_search_private_data.htmlUsername: Reviewer_E-MTAB-9268Password: hqhgiiqx10X dataset (GEO)To review GEO accession GSE153916:Go to https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE153916Enter token mzoxeoigpranfub into the box
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Transcriptomics analysis of neurogenesis by striatal astrocytes upon Rbpj-K deletionNCBI Gene Expression Omnibus, GSE153916.
Article and author information
Author details
Funding
Svenska Forskningsrådet Formas
- Jonas Frisén
Cancerfonden
- Jonas Frisén
Stiftelsen för Strategisk Forskning
- Jonas Frisén
H2020 European Research Council
- Jonas Frisén
Knut och Alice Wallenbergs Stiftelse
- Jonas Frisén
Torsten Söderbergs Stiftelse
- Jonas Frisén
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal experimental procedures were approved by the Stockholms Norra Djurförsöksetiska Nämnd (Permit reference numbers N571-11 and N155-16)
Copyright
© 2020, Magnusson et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Activation of a neural stem cell transcriptional program in parenchymal astrocytes
eLife 9:e59733.
https://doi.org/10.7554/eLife.59733
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