PUBLICATION

Novel mutations affecting axon guidance in zebrafish and a role for plexin signalling in the guidance of trigeminal and facial nerve axons

Authors
Tanaka, H., Maeda, R., Shoji, W., Wada, H., Masai, I., Shiraki, T., Kobayashi, M., Nakayama, R., and Okamoto, H.
ID
ZDB-PUB-070820-12
Date
2007
Source
Development (Cambridge, England)   134(18): 3259-3269 (Journal)
Registered Authors
Kobayashi, Megumi, Masai, Ichiro, Okamoto, Hitoshi, Shiraki, Toshiyuki, Shoji, Wataru, Tanaka, Hideomi, Wada, Hironori
Keywords
none
MeSH Terms
  • Axons/physiology*
  • Facial Nerve/embryology*
  • Motor Neurons/physiology
  • Mutation
  • Semaphorins/physiology
  • Animals
  • Trigeminal Nerve/embryology*
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/physiology*
  • Receptors, Cell Surface/genetics
  • Receptors, Cell Surface/physiology*
  • Embryonic Development/genetics*
(all 14)
PubMed
17699608 Full text @ Development
Abstract
In zebrafish embryos, the axons of the posterior trigeminal (Vp) and facial (VII) motoneurons project stereotypically to a small number of target muscles derived from the first and second branchial arches (BA1, BA2). Use of the Islet1 (Isl1)-GFP transgenic line enabled precise real-time observations of the growth cone behaviour of the Vp and VII motoneurons within BA1 and BA2. Screening for N-ethyl-N-nitrosourea-induced mutants identified seven distinct mutations affecting different steps in the axonal pathfinding of these motoneurons. The class 1 mutations caused severe defasciculation and abnormal pathfinding in both Vp and VII motor axons before they reached their target muscles in BA1. The class 2 mutations caused impaired axonal outgrowth of the Vp motoneurons at the BA1-BA2 boundary. The class 3 mutation caused impaired axonal outgrowth of the Vp motoneurons within the target muscles derived from BA1 and BA2. The class 4 mutation caused retraction of the Vp motor axons in BA1 and abnormal invasion of the VII motor axons in BA1 beyond the BA1-BA2 boundary. Time-lapse observations of the class 1 mutant, vermicelli (vmc), which has a defect in the plexin A3 (plxna3) gene, revealed that Plxna3 acts with its ligand Sema3a1 for fasciculation and correct target selection of the Vp and VII motor axons after separation from the common pathways shared with the sensory axons in BA1 and BA2, and for the proper exit and outgrowth of the axons of the primary motoneurons from the spinal cord.
Genes / Markers
Figures
Figure Gallery (10 images)
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Expression
Phenotype
Mutations / Transgenics
Allele Construct Type Affected Genomic Region
rw0TgTransgenic Insertion
    rw218
      Point Mutation
      rw260
        Point Mutation
        rw309
          Point Mutation
          rw314
            Point Mutation
            rw357
              Point Mutation
              rw395
                Point Mutation
                rw413
                  Point Mutation
                  rw453
                    Point Mutation
                    rw520
                      Point Mutation
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                      Human Disease / Model
                      No data available
                      Sequence Targeting Reagents
                      1 - 10 of 10
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                      Fish
                      Antibodies
                      No data available
                      Orthology
                      No data available
                      Engineered Foreign Genes
                      Marker Marker Type Name
                      GFPEFGGFP
                      1 - 1 of 1
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                      Mapping
                      Entity Type Entity Symbol Location
                      ESTfj56g03Chr: 8 Details
                      GENEblnChr: 14 Details
                      GENEkofChr: 4 Details
                      GENEloeChr: 24 Details
                      GENEmknChr: 7 Details
                      GENEplxna3Chr: 8 Details
                      GENErgdChr: 5 Details
                      GENEtpsChr: 22 Details
                      SSLPz15045Chr: 8 Details
                      1 - 9 of 9
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