Delta/Notch signaling promotes formation of zebrafish neural crest by repressing Neurogenin 1 function.
In zebrafish, cells at the lateral edge of the neural plate become Rohon-Beard primary sensory neurons or neural crest. Delta/Notch signaling is required for neural crest formation. ngn1 is expressed in primary neurons; inhibiting Ngn1 activity prevents Rohon-Beard cell formation but not formation of other primary neurons. Reducing Ngn1 activity in embryos lacking Delta/Notch signaling restores neural crest formation, indicating Delta/Notch signaling inhibits neurogenesis without actively promoting neural crest. Ngn1 activity is also required for later development of dorsal root ganglion sensory neurons; however, Rohon-Beard neurons and dorsal root ganglion neurons are not necessarily derived from the same precursor cell. We propose that temporally distinct episodes of Ngn1 activity in the same precursor population specify these two different types of sensory neurons.
Cornell
Robert A
RA
Institute of Neuroscience, 1254 University of Oregon, Eugene 97403, USA. robert-cornell@uiowa.edu
Eisen
Judith S
JS
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000502:physiology; D005727:Ganglia, Spinal / Q000196:embryology; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000235:genetics*; D009432:Neural Crest / Q000502:physiology*; D009475:Neurons, Afferent / Q000166:cytology; D051880:Receptors, Notch; D015534:Trans-Activators / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D015027:Zebrafish / Q000502:physiology*; D029961:Zebrafish Proteins
D051792:Basic Helix-Loop-Helix Proteins; D018398:Homeodomain Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D051880:Receptors, Notch; D015534:Trans-Activators; D014157:Transcription Factors; D029961:Zebrafish Proteins; C064045:delta protein; C486337:neurog1 protein, zebrafish