PUBLICATION

Axon tracts guide zebrafish facial branchiomotor neuron migration through the hindbrain

Authors
Wanner, S.J., and Prince, V.E.
ID
ZDB-PUB-130125-9
Date
2013
Source
Development (Cambridge, England)   140(4): 906-915 (Journal)
Registered Authors
Prince, Victoria E., Wanner, Sarah
Keywords
none
MeSH Terms
  • Animals
  • Axons/physiology*
  • Cell Movement/physiology*
  • Facial Nerve/cytology*
  • Immunohistochemistry
  • Microscopy, Confocal
  • Models, Neurological
  • Morpholinos/genetics
  • Motor Neurons/physiology*
  • Rhombencephalon/embryology*
  • Zebrafish/embryology*
PubMed
23325758 Full text @ Development
Abstract

Appropriate localization of neurons within the brain is a crucial component of the establishment of neural circuitry. In the zebrafish hindbrain, the facial branchiomotor neurons (FBMNs) undergo a chain-like tangential migration from their birthplace in rhombomere (r) 4 to their final destination in r6/r7. Here, we report that ablation of either the cell body or the trailing axon of the leading FBMN, or 'pioneer' neuron, blocks the migration of follower FBMNs into r5. This demonstrates that the pioneer neuron and its axon are crucial to the early migration of FBMNs. Later migration from r5 to r6 is not dependent on pioneer neurons but on the medial longitudinal fasciculus (MLF), a bundle of axons lying ventral to the FBMNs. We find that MLF axons enter r5 only after the pioneer neuron has led several followers into this region; the MLF is then contacted by projections from the FBMNs. The interactions between FBMNs and the MLF are important for migration from r5 to r6, as blocking MLF axons from entering the hindbrain can stall FBMN migration in r5. Finally, we have found that the adhesion molecule Cdh2 (N-cadherin) is important for interactions between the MLF and FBMNs, as well as for interactions between the trailing axon of the pioneer neuron and follower FBMNs. Interestingly, migration of pioneer neurons is independent of both the MLF and Cdh2, suggesting pioneer migration relies on independent cues.

Genes / Markers
Figures
Expression
Phenotype
Mutation and Transgenics
Human Disease / Model Data
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping
Errata and Notes