title: Nutrition-responsive glia control exit of neural stem cells from quiescence.
abstract: 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.
authors.affiliation: The Gurdon Institute and Department of Physiology, Development, and Neuroscience, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK.
authors.forename: James M
authors.initials: JM
authors.lastname: Chell
authors.forename: Andrea H
authors.initials: AH
authors.lastname: Brand
mesh_terms: D000818:Animals; D004032:Diet; D004330:Drosophila / Q000166:cytology* / Q000196:embryology / Q000378:metabolism*; D005216:Fat Body / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D058953:Neural Stem Cells / Q000166:cytology*; D009457:Neuroglia / Q000166:cytology; D013002:Somatomedins / Q000378:metabolism
chemical_list: D013002:Somatomedins