Neural stem cells lose telomerase activity upon differentiating into astrocytes
T Miura1, Y Katakura, K Yamamoto
1Department of Genetic Resources Technology, Kyushu University, Fukuoka, 812-8581, Japan.
Cytotechnology
|November 13, 2008
Summary
Transforming neural stem cells into astrocytes with TGF-beta inhibits telomerase activity. This occurs via down-regulation of mouse telomerase reverse transcriptase (mTERT) expression, mediated by c-myc repression.
Area of Science:
- Stem cell biology
- Molecular biology
- Neuroscience
Background:
- Serum-free mouse embryo (SFME) cells serve as a neural stem cell model.
- Telomerase maintains telomere length and is typically absent in normal somatic cells.
- Understanding neural stem cell differentiation mechanisms is crucial.
Purpose of the Study:
- To investigate telomerase activity regulation during neural stem cell differentiation.
- To analyze changes in telomerase activity and mouse telomerase reverse transcriptase (mTERT) expression upon astrocyte differentiation.
- To elucidate the role of c-myc in regulating mTERT during this process.
Main Methods:
- SFME cells were treated with TGF-beta to induce differentiation into astrocytes.
- Cell morphology, growth rate, and glial fibrillary acidic protein (GFAP) expression were assessed.
- Telomerase activity, mTERT expression, and c-myc expression levels were measured.
- mTERT promoter activity was analyzed using reporter assays.
Main Results:
- TGF-beta treatment induced SFME cell differentiation into astrocytes, marked by morphological changes and GFAP expression.
- Differentiation led to inhibition of telomerase activity and repression of mTERT expression.
- TGF-beta treatment downregulated c-myc expression.
- mTERT promoter activity was significantly reduced in TGF-beta-treated cells, correlating with c-myc repression.
Conclusions:
- TGF-beta induces neural stem cell differentiation into astrocytes in SFME cells.
- Astrocytic differentiation is associated with suppressed telomerase activity and mTERT expression.
- The c-myc pathway plays a critical role in repressing mTERT expression during astrocytic differentiation.
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