ZFIN ID: ZDB-PUB-170526-16
Pioneer neurog1 expressing cells ingress into the otic epithelium and instruct neuronal specification.
Hoijman, E., Fargas, L., Blader, P., Alsina, B.
Date: 2017
Source: eLIFE   6: (Journal)
Registered Authors: Alsina, Berta, Blader, Patrick
Keywords: developmental biology, neuroscience, stem cells, zebrafish
MeSH Terms:
  • Animals
  • Basic Helix-Loop-Helix Transcription Factors/metabolism*
  • Body Patterning
  • Cell Movement
  • Ear/embryology*
  • Epithelium/embryology*
  • Nerve Tissue Proteins/metabolism*
  • Nervous System/embryology*
  • Neuroepithelial Cells/physiology*
  • Neurogenesis*
  • Zebrafish/embryology*
  • Zebrafish Proteins/metabolism*
PubMed: 28537554 Full text @ Elife
Neural patterning involves regionalised cell specification. Recent studies indicate that cell dynamics play instrumental roles in neural pattern refinement and progression, but the impact of cell behaviour and morphogenesis on neural specification is not understood. Here we combine 4D analysis of cell behaviours with dynamic quantification of proneural expression to uncover the construction of the zebrafish otic neurogenic domain. We identify pioneer cells expressing neurog1 outside the otic primordium that migrate and ingress into the epithelialising placode to become the first otic neuronal progenitors. Subsequently, neighbouring cells express neurog1 inside the placode, and apical symmetric divisions amplify the specified pool. Interestingly, pioneer cells delaminate shortly after ingression. Ablation experiments reveal that pioneer cells promote neurog1 expression in other otic cells. Finally, ingression relies on the epithelialisation timing controlled by FGF activity. We propose a novel view for otic neurogenesis integrating cell dynamics whereby ingression of pioneer cells instructs neuronal specification.