PUBLICATION

Essential roles of zebrafish rtn4/Nogo paralogues in embryonic development

Authors
Pinzón-Olejua, A., Welte, C., Abdesselem, H., Málaga-Trillo, E., Stuermer, C.A.
ID
ZDB-PUB-140513-98
Date
2014
Source
Neural Development   9: 8 (Journal)
Registered Authors
Málaga-Trillo, Edward
Keywords
none
MeSH Terms
  • Animals, Genetically Modified
  • Neurons/metabolism*
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism
  • Zebrafish Proteins/physiology*
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Animals
  • Down-Regulation
  • Brain/embryology
  • Myelin Proteins/genetics
  • Myelin Proteins/metabolism
  • Myelin Proteins/physiology*
  • Retina/embryology
(all 14)
PubMed
24755266 Full text @ Neural Dev.
Abstract
As a consequence of gene/genome duplication, the RTN4/Nogo gene has two counterparts in zebrafish: rtn4a and rtn4b. The shared presence of four specific amino acid motifs-M1 to M4-in the N-terminal region of mammalian RTN4, and zebrafish Rtn4b suggests that Rtn4b is the closest homologue of mammalian Nogo-A.
To explore their combined roles in zebrafish development, we characterized the expression patterns of rtn4a and rtn4b in a comparative manner and performed morpholino-mediated knockdowns. Although both genes were coexpressed in the neural tube and developing brain at early stages, they progressively acquired distinct expression domains such as the spinal cord (rtn4b) and somites (rtn4a). Downregulation of rtn4a and rtn4b caused severe brain abnormalities, with rtn4b knockdown severely affecting the spinal cord and leading to immobility. In addition, the retinotectal projection was severely affected in both morphants, as the retina and optic tectum appeared smaller and only few retinal axons reached the abnormally reduced tectal neuropil. The neuronal defects were more persistent in rtn4b morphants. Moreover, the latter often lacked pectoral fins and lower jaws and had malformed branchial arches. Notably, these defects led to larval death in rtn4b, but not in rtn4a morphants.
In contrast to mammalian Nogo-A, its zebrafish homologues, rtn4a and particularly rtn4b, are essential for embryonic development and patterning of the nervous system.
Genes / Markers
Figures
Figure Gallery (11 images) / 2
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Expression
Phenotype
Mutations / Transgenics
Allele Construct Type Affected Genomic Region
ml2TgTransgenic Insertion
    rw0TgTransgenic Insertion
      s356tTgTransgenic Insertion
        t10TgTransgenic Insertion
          1 - 4 of 4
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          Human Disease / Model
          No data available
          Sequence Targeting Reagents
          Target Reagent Reagent Type
          rtn4aMO9-rtn4aMRPHLNO
          rtn4aMO10-rtn4aMRPHLNO
          rtn4aMO11-rtn4aMRPHLNO
          rtn4aMO12-rtn4aMRPHLNO
          rtn4aMO13-rtn4aMRPHLNO
          rtn4aMO14-rtn4aMRPHLNO
          rtn4bMO1-rtn4bMRPHLNO
          rtn4bMO2-rtn4bMRPHLNO
          1 - 8 of 8
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          Fish
          Antibodies
          Orthology
          No data available
          Engineered Foreign Genes
          Marker Marker Type Name
          GFPEFGGFP
          1 - 1 of 1
          Show
          Mapping
          No data available