Stem cells living with a Notch
During the development of the central and peripheral nervous systems (CNS,PNS) of Drosophila, Notch signaling specifies individual cells among an equipotent cluster in the ectoderm to become neuralprogenitors: neuroblasts (NBs) in the CNS (Artavanis-Tsakonas et al., 1991) or sensory organ precursor (SOP) cells in the PNS(Furukawa et al., 1992; Schweisguth and Posakony, 1992). Functionally, loss ofNotch signaling in temperature-sensitive Drosophila strains(harboring mutations in the Notch locus) causes an expansion of escargot Genetic loss- or gain-of-function studies in Drosophila also suggest that Notch signaling in EBs plays an active role in lineagecommitment and terminal differentiation into the EC population(Micchelli and Perrimon, 2006; Ohlstein and Spradling, 2006;Ohlstein and Spradling, 2007; Takashima et al., 2011).
Drosophila, Notch pathway activation dictates symmetrical division fact, Bmi1 cells can compensate for ablation of the Lgr5 cell of ISCs and controls their proliferation via the JAK-STAT and JNK population, thereby maintaining intestinal homeostasis (Tian et al., pathway. In addition, the levels of Notch signaling also determine 2011). Elegant studies in zebrafish and the mouse embryo showed that a subset of endothelial cells move out from the ventral wall of theDA into the sub-aortic space and transform into presumptive HSCs by a process termed endothelial hematopoietic transition (Bertrandet al., 2010; Boisset et al., 2010; Kissa and Herbomel, 2010; Lam et al., 2010).
EMBO J. 31, 2473-2485
Dualroles of Notch in regulation of apically restricted mitosis and apicobasal polarity of neuroepithelial cells. Roles ofthe basic helix-loop-helix genes Hes1 and Hes5 in expansion of neural stem cells of the developing brain.
A., Kempermann, G., Taylor, V. and Giachino, C. (2010). Quiescent and
A critical requirement for notch signaling in maintenance of the quiescent skeletal muscle stem cell state. Combinedeffects of Notch signaling and cytokines induce a multiple log increase in precursors with lymphoid and myeloid reconstituting ability.
D. E., van Es, J. H., Abo, A., Kujala, P., Peters, P. J. et al. (2009). Single Lgr5 stem cells build crypt-villus structures in vitro without a mesenchymal niche
Identification of the haematopoietic stem cell niche and control of the niche size. Notch1 and its ligands Delta-like and Jagged are expressed and active in distinct cell populations in the postnatal mouse brain.