title: How Notch establishes longitudinal axon connections between successive segments of the Drosophila CNS.
abstract: Development of the segmented central nerve cords of vertebrates and invertebrates requires connecting successive neuromeres. Here, we show both how a pathway is constructed to guide pioneer axons between segments of the Drosophila CNS, and how motility of the pioneers along that pathway is promoted. First, canonical Notch signaling in specialized glial cells causes nearby differentiating neurons to extrude a mesh of fine projections, and shapes that mesh into a continuous carpet that bridges from segment to segment, hugging the glial surface. This is the direct substratum that pioneer axons follow as they grow. Simultaneously, Notch uses an alternate, non-canonical signaling pathway in the pioneer growth cones themselves, promoting their motility by suppressing Abl signaling to stimulate filopodial growth while presumably reducing substratum adhesion. This propels the axons as they establish the connection between successive segments.
authors: National Institute of Neurological Disorders and Stroke and National Human Genome Research Institute NIH, Bethesda, MD 20892, USA.
authors: Irina
authors: I
authors: Kuzina
authors: Jeong K
authors: JK
authors: Song
authors: Edward
authors: E
authors: Giniger
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001369:Axons / Q000378:metabolism / Q000502:physiology*; D002450:Cell Communication / Q000235:genetics* / Q000502:physiology; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology; D048708:Cell Growth Processes / Q000235:genetics / Q000502:physiology; D002490:Central Nervous System / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D004625:Embryo, Nonmammalian; D020439:Growth Cones / Q000378:metabolism / Q000502:physiology; D008954:Models, Biological; D009414:Nerve Growth Factors / Q000378:metabolism; D000075386:Netrin Receptors; D000075388:Netrin-1; D009457:Neuroglia / Q000378:metabolism / Q000502:physiology; D011554:Pseudopodia / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D011956:Receptors, Cell Surface / Q000378:metabolism; D051880:Receptors, Notch / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D013569:Synapses / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D025521:Tumor Suppressor Proteins / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; C497759:N protein, Drosophila; D009414:Nerve Growth Factors; D000075386:Netrin Receptors; D011956:Receptors, Cell Surface; D051880:Receptors, Notch; D025521:Tumor Suppressor Proteins; D000075388:Netrin-1