title: Specified neural progenitors sort to form sharp domains after noisy Shh signaling.
abstract: Sharply delineated domains of cell types arise in developing tissues under instruction of inductive signal (morphogen) gradients, which specify distinct cell fates at different signal levels. The translation of a morphogen gradient into discrete spatial domains relies on precise signal responses at stable cell positions. However, cells in developing tissues undergoing morphogenesis and proliferation often experience complex movements, which may affect their morphogen exposure, specification, and positioning. How is a clear pattern achieved with cells moving around? Using in toto imaging of the zebrafish neural tube, we analyzed specification patterns and movement trajectories of neural progenitors. We found that specified progenitors of different fates are spatially mixed following heterogeneous Sonic Hedgehog signaling responses. Cell sorting then rearranges them into sharply bordered domains. Ectopically induced motor neuron progenitors also robustly sort to correct locations. Our results reveal that cell sorting acts to correct imprecision of spatial patterning by noisy inductive signals.
authors.affiliation: Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Fengzhu
authors.initials: F
authors.lastname: Xiong
authors.forename: Andrea R
authors.initials: AR
authors.lastname: Tentner
authors.forename: Peng
authors.initials: P
authors.lastname: Huang
authors.forename: Arnaud
authors.initials: A
authors.lastname: Gelas
authors.forename: Kishore R
authors.initials: KR
authors.lastname: Mosaliganti
authors.forename: Lydie
authors.initials: L
authors.lastname: Souhait
authors.forename: Nicolas
authors.initials: N
authors.lastname: Rannou
authors.forename: Ian A
authors.initials: IA
authors.lastname: Swinburne
authors.forename: Nikolaus D
authors.initials: ND
authors.lastname: Obholzer
authors.forename: Paul D
authors.initials: PD
authors.lastname: Cowgill
authors.forename: Alexander F
authors.initials: AF
authors.lastname: Schier
authors.forename: Sean G
authors.initials: SG
authors.lastname: Megason
mesh_terms: D000818:Animals; D002465:Cell Movement; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000378:metabolism; D053823:Hedgehog Proteins / Q000378:metabolism; D009024:Morphogenesis; D058953:Neural Stem Cells / Q000378:metabolism*; D054259:Neural Tube / Q000166:cytology*; D015398:Signal Transduction; D015027:Zebrafish / Q000196:embryology* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000378:metabolism
chemical_list: D053823:Hedgehog Proteins; C524053:Shha protein, zebrafish; D029961:Zebrafish Proteins