Signaling through BMPR-IA regulates quiescence and long-term activity of neural stem cells in the adult hippocampus.
SummaryNeural stem cells (NSCs) in the adult hippocampus divide infrequently, and the molecules that modulate their quiescence are largely unknown. Here, we show that bone morphogenetic protein (BMP) signaling is active in hippocampal NSCs, downstream of BMPR-IA. BMPs reversibly diminish proliferation of cultured NSCs while maintaining their undifferentiated state. In vivo, acute blockade of BMP signaling in the hippocampus by intracerebral infusion of Noggin first recruits quiescent NSCs into the cycle and increases neurogenesis; subsequently, it leads to decreased stem cell division and depletion of precursors and newborn neurons. Consistently, selective ablation of Bmpr1a in hippocampal …
Symmetric expansion of neural stem cells from the adult olfactory bulb is driven by astrocytes via WNT7A.
Adult neural stem cells (NSCs) located in the subventricular zone (SVZ) persistently produce new neurons destined to the olfactory bulb (OB). Recent research suggests that the OB is also a source of NSCs that remains largely unexplored. Using single/dual-labeling procedures, we address the existence of NSCs in the innermost layers of the OB. In vivo, these cells are more quiescent that their SVZ counterparts, but after in vitro expansion, they behave similarly. Self-renewal and proliferation assays in co-culture with niche astrocytes indicate that OB-glia restricts NSC activity whereas SVZ-glia has the opposite effect. Gene expression profiling identifies WNT7A as a key SVZ-glial factor lac…