PUBLICATION

Segmental homologies among reticulospinal neurons in the hindbrain of the zebrafish larva

Authors
Metcalfe, W.K., Mendelson, B., and Kimmel, C.B.
ID
ZDB-PUB-961014-770
Date
1986
Source
The Journal of comparative neurology   251: 147-159 (Journal)
Registered Authors
Kimmel, Charles B., Mendelson, Bruce, Metcalfe, Walt
Keywords
none
MeSH Terms
  • Animals
  • Cyprinidae/anatomy & histology*
  • Dendrites/classification
  • Efferent Pathways
  • Functional Laterality
  • Horseradish Peroxidase
  • Larva
  • Motor Neurons/classification*
  • Rhombencephalon/anatomy & histology*
  • Spinal Cord/anatomy & histology*
  • Zebrafish/anatomy & histology*
  • Zebrafish/growth & development
PubMed
3782495 Full text @ J. Comp. Neurol.
Abstract
We have examined the morphology of identified reticulospinal neurons in larval zebrafish by retrogradely labeling them with horseradish peroxidase. We described the morphology of 27 different types of reticulospinal neurons found in the hindbrain 5 days after fertilization. Nineteen of these types are present as single identified neurons on each side of the brain; the others are present as pairs or small groups of cells. The hindbrain reticulospinal neurons are present in seven bilateral clusters that are spaced periodically along the neuraxis. Each cluster contains two to five different types of reticulospinal neurons. Cells with similar morphological features are found in adjacent clusters. By considering cell position within the cluster and axon pathway, nearly all of the cells can be assigned to one of about seven serially repeated classes. Independent morphological features of the cells support the same classification. We propose that the clusters represent hindbrain segments and that the neurons of the same class that are present in the different clusters are segmental homologues. Assuming that this series evolved by successive duplications and divergence of the primitive segments, we have analyzed the changes that may have occurred during the evolution of each new segment. Changes between ipsilaterally and contralaterally projecting axons may have occurred several times during the evolution of the series. In addition, cells may have been added or deleted.
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