Nutrition-Responsive Glia Control Exit of Neural Stem Cells from Quiescence

• Published in: Cell Vol. 143; no. 7; pp. 1161 - 1173
• Main Authors: Chell, James M., Brand, Andrea H.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 23-12-2010; Elsevier; Cell Press
• Subjects: Animals; BASIC BIOLOGICAL SCIENCES; Biochemistry & Molecular Biology; Cell Biology; Diet; Drosophila; Drosophila - cytology; Drosophila - embryology; Drosophila - metabolism; Fat Body - metabolism; Gene Expression Regulation, Developmental; Neural Stem Cells - cytology; Neuroglia - cytology; Somatomedins - metabolism
• ISSN: 0092-8674; 1097-4172
• DOI: 10.1016/j.cell.2010.12.007

The systemic regulation of stem cells ensures that they meet the needs of the organism during growth and in response to injury. A key point of regulation is the decision between quiescence and proliferation. During development, Drosophila neural stem cells (neuroblasts) transit through a period of quiescence separating distinct embryonic and postembryonic phases of proliferation. It is known that neuroblasts exit quiescence via a hitherto unknown pathway in response to a nutrition-dependent signal from the fat body. We have identified a population of glial cells that produce insulin/IGF-like peptides in response to nutrition, and we show that the insulin/IGF receptor pathway is necessary for neuroblasts to exit quiescence. The forced expression of insulin/IGF-like peptides in glia, or activation of PI3K/Akt signaling in neuroblasts, can drive neuroblast growth and proliferation in the absence of dietary protein and thus uncouple neuroblasts from systemic control.
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► Stellate glia express insulin/IGF-like peptides (dILPs) in response to nutrition ► Insulin receptor/PI3K signaling is required for neural stem cell (NSC) reactivation ► Glial dILP expression is sufficient to reactivate NSCs irrespective of nutrition ► Glial signaling is essential for NSC exit from quiescence