title: Sonic hedgehog signaling switches the mode of division in the developing nervous system.
abstract: The different modes of stem cell division are tightly regulated to balance growth and differentiation during organ development and homeostasis, and these regulatory processes are subverted in tumor formation. Here, we developed markers that provided the single-cell resolution necessary to quantify the three modes of division taking place in the developing nervous system in vivo: self-expanding, PP; self-replacing, PN; and self-consuming, NN. Using these markers and a mathematical model that predicts the dynamics of motor neuron progenitor division, we identify a role for the morphogen Sonic hedgehog in the maintenance of stem cell identity in the developing spinal cord. Moreover, our study provides insight into the process linking lineage commitment to neurogenesis with changes in cell-cycle parameters. As a result, we propose a challenging model in which the external Sonic hedgehog signal dictates stem cell identity, reflected in the consequent readjustment of cell-cycle parameters.
authors.affiliation: Instituto de Biología Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac 20, Barcelona 08028, Spain.
authors.forename: Murielle
authors.initials: M
authors.lastname: Saade
authors.forename: Irene
authors.initials: I
authors.lastname: Gutiérrez-Vallejo
authors.forename: Gwenvael
authors.initials: G
authors.lastname: Le Dréau
authors.forename: M Angeles
authors.initials: MA
authors.lastname: Rabadán
authors.forename: David G
authors.initials: DG
authors.lastname: Miguez
authors.forename: Javier
authors.initials: J
authors.lastname: Buceta
authors.forename: Elisa
authors.initials: E
authors.lastname: Martí
mesh_terms: D000818:Animals; D002453:Cell Cycle / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D048708:Cell Growth Processes / Q000502:physiology; D002642:Chick Embryo; D002645:Chickens; D053823:Hedgehog Proteins / Q000235:genetics / Q000378:metabolism*; D008959:Models, Neurological; D009046:Motor Neurons / Q000166:cytology* / Q000378:metabolism*; D058953:Neural Stem Cells / Q000166:cytology* / Q000378:metabolism*; D055495:Neurogenesis; D015398:Signal Transduction
chemical_list: D053823:Hedgehog Proteins