PUBLICATION

Semaphorin 3d guides laterality of retinal ganglion cell projections in zebrafish

Authors
Sakai, J.A., and Halloran, M.C.
ID
ZDB-PUB-060213-1
Date
2006
Source
Development (Cambridge, England)   133(6): 1035-1044 (Journal)
Registered Authors
Halloran, Mary, Sakai, Jill
Keywords
Semaphorin, Axon guidance, Retinal ganglion cell, Optic chiasm, Zebrafish
MeSH Terms
  • Animals
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
  • Nerve Growth Factors/genetics
  • Nerve Growth Factors/metabolism*
  • DNA, Antisense/genetics
  • Semaphorins/genetics
  • Semaphorins/metabolism*
  • Vision, Ocular/physiology*
  • Gene Expression Regulation, Developmental
  • Cell Proliferation
  • Functional Laterality/physiology*
  • Retinal Ganglion Cells/cytology
  • Retinal Ganglion Cells/metabolism*
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish/metabolism*
  • Time Factors
  • Growth Cones/metabolism
(all 19)
PubMed
16467361 Full text @ Development
Abstract
The optic chiasm is an important choice point at which retinal ganglion cell (RGC) axons either cross the midline to innervate the contralateral brain or turn back to innervate the ipsilateral brain. Guidance cues that regulate this decision, particularly those directing the midline crossing of contralateral axons, are still not well understood. Here we show that Sema3d, a secreted semaphorin expressed at the midline, guides the crossing of RGC axons in zebrafish. Both Sema3d knockdown and ubiquitous overexpression induced aberrant ipsilateral projections, suggesting that Sema3d normally guides axons into the contralateral optic tract. Live imaging in vivo showed that RGC growth cones responded to ubiquitous Sema3d overexpression by pausing for extended periods and increasing their exploratory behavior at the midline, suggesting that Sema3d overexpression causes the midline environment to become less favorable for RGC axon extension. Interestingly, Sema3d overexpression did not affect growth cone behaviors before the midline, suggesting that RGC axons normally respond to Sema3d only upon reaching the midline. After Sema3d knockdown, growth cones grew across the midline but then paused or repeatedly retracted, impairing their ability to leave the midline region. Our results indicate that a proper balance of Sema3d is needed at the midline for the progression of RGC axons from the chiasm midline into the contralateral optic tract.
Genes / Markers
Figures
Figure Gallery (6 images)
Show all Figures
Expression
Gene Antibody Fish Conditions Stage Qualifier Anatomy Assay Figure
alcamaWTstandard conditionsDay 5IHC
sema3dWTstandard conditionsPrim-25ISH
sema3dWTstandard conditionsDay 5ISH
1 - 3 of 3
Show
Phenotype
No data available
Mutations / Transgenics
Allele Construct Type Affected Genomic Region
mi3TgTransgenic Insertion
    1 - 1 of 1
    Show
    Human Disease / Model
    No data available
    Sequence Targeting Reagents
    Target Reagent Reagent Type
    sema3dMO2-sema3dMRPHLNO
    1 - 1 of 1
    Show
    Fish
    Fish
    mi3Tg
    WT
    1 - 2 of 2
    Show
    Antibodies
    No data available
    Orthology
    No data available
    Engineered Foreign Genes
    No data available
    Mapping
    No data available
    Your Input Welcome
    We welcome your input and comments. Please use this form to recommend updates to the information in ZFIN. We appreciate as much detail as possible and references as appropriate. We will review your comments promptly.
    Citation
    Sakai, J.A., and Halloran, M.C. (2006) Semaphorin 3d guides laterality of retinal ganglion cell projections in zebrafish. Development (Cambridge, England). 133(6):1035-1044.