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10:07
Assessing Teratogenic Changes in a Zebrafish Model of Fetal Alcohol Exposure
Published on: March 20, 2012
Ethanol alters gene expression and cell organization during optic vesicle evagination
A Santos-Ledo1, F Cavodeassi, H Carreño
1Departamento de Biología Celular y Patología, IBSAL-Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, Spain.
Neuroscience
|July 30, 2013
Summary
Ethanol exposure during early development disrupts eye formation by altering gene expression and cell organization. This leads to abnormal optic vesicle development and contributes to birth defects like cyclopia.
Area of Science:
- Developmental biology
- Teratology
- Neuroscience
Background:
- Ethanol is a known teratogen affecting vertebrate development.
- Ethanol exposure during early brain formation can cause optic vesicle fusion, leading to synophthalmia or cyclopia.
- The precise mechanisms of ethanol's teratogenic effects on optic vesicle morphogenesis are not well understood.
Purpose of the Study:
- To investigate the effects of ethanol on cell organization and gene expression during optic vesicle evagination.
- To elucidate the molecular and cellular mechanisms underlying ethanol-induced eye malformations.
Main Methods:
- In situ hybridization
- Electron microscopy
- Immunohistochemistry
Main Results:
- Ethanol exposure alters the expression of key eye morphogenesis genes (e.g., rx3/1, six3a).
- Ethanol disrupts the acquisition of neuroepithelial features and fusiform cell shape in the eye field.
- Ethanol interferes with tight junction formation and retinal progenitor cell polarization (indicated by zo1 mis-localization).
- Ethanol-induced cyclopia differs from that in genetic mutants, suggesting diverse targets.
Conclusions:
- Ethanol disrupts optic vesicle morphogenesis by altering gene expression patterns and cell polarity.
- Ethanol's teratogenic effects involve not only gene expression changes and cell death but also alterations in cell morphology and organization.
Keywords:
ISHMETMHBSEMTUNELZO-1cell polaritycyclopic mutantseye specificationhours post-fertilizationhpfin situ hybridizationmesenchymal–epithelial transitionmidbrain–hindbrain boundarymorphogenesisoepone-eye pinheadqRT-PCRquantitative real-time polymerase chain reactionsomites stagessstandard error of meanterminal deoxynucleotidyl transferase dUTP nick end labelingzonula-occludens-1
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