1. alpha-Tanycytes of the adult hypothalamic third ventricle include distinct populations of FGF-responsive neural progenitors
- Author
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Robins, S.C., Stewart, I., McNay, D.E., Taylor, V., Giachino, C., Götz, M., Ninkovic, J., Briancon, N., Maratos-Flier, E., Flier, J.S., Kokoeva, M.V., and Placzek, M.
- Subjects
Aging ,Epidermal Growth Factor ,Integrases ,Ependymoglial Cells ,Hypothalamus ,Immunohistochemistry ,Excitatory Amino Acid Transporter 1 ,Fibroblast Growth Factors ,Mice, Inbred C57BL ,Mice ,Neural Stem Cells ,Spheroids, Cellular ,Glial Fibrillary Acidic Protein ,Animals ,Fibroblast Growth Factor 10 ,Neuroglia ,Cell Proliferation ,Signal Transduction ,Third Ventricle - Abstract
Emerging evidence suggests that new cells, including neurons, can be generated within the adult hypothalamus, suggesting the existence of a local neural stem/progenitor cell niche. Here, we identify α-tanycytes as key components of a hypothalamic niche in the adult mouse. Long-term lineage tracing in vivo using a GLAST::CreER(T2) conditional driver indicates that α-tanycytes are self-renewing cells that constitutively give rise to new tanycytes, astrocytes and sparse numbers of neurons. In vitro studies demonstrate that α-tanycytes, but not β-tanycytes or parenchymal cells, are neurospherogenic. Distinct subpopulations of α-tanycytes exist, amongst which only GFAP-positive dorsal α2-tanycytes possess stem-like neurospherogenic activity. Fgf-10 and Fgf-18 are expressed specifically within ventral tanycyte subpopulations; α-tanycytes require fibroblast growth factor signalling to maintain their proliferation ex vivo and elevated fibroblast growth factor levels lead to enhanced proliferation of α-tanycytes in vivo. Our results suggest that α-tanycytes form the critical component of a hypothalamic stem cell niche, and that local fibroblast growth factor signalling governs their proliferation.
- Published
- 2013