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Updated: Aug 16, 2026
08:28
Visualization of Tangential Cell Migration in the Developing Chick Optic Tectum
Published on: October 24, 2018
Extraocular mesenchyme patterns the optic vesicle during early eye development in the embryonic chick
S Fuhrmann1, E M Levine, T A Reh
1Department of Biological Structure, Box 357420, University of Washington, Seattle, WA 98195, USA.
Development (Cambridge, England)
|October 12, 2000
Summary
Extraocular mesenchyme is crucial for retinal pigmented epithelium (RPE) development in vertebrate eyes. This tissue induces RPE-specific genes and suppresses neural retina markers, guiding optic vesicle patterning.
Area of Science:
- Developmental biology
- Ophthalmology
- Cell biology
Background:
- Vertebrate eye development originates from the ventral forebrain's neuroepithelium, forming the optic vesicle.
- Extraocular tissues, including surface ectoderm and mesenchyme, are vital for eye growth and differentiation.
Purpose of the Study:
- To investigate the role of extraocular mesenchyme in regulating retinal pigmented epithelium (RPE) patterning and differentiation.
- To understand the molecular mechanisms underlying early eye development in chick optic vesicle explants.
Main Methods:
- Utilized explant cultures of chick optic vesicles.
- Analyzed the expression of RPE-specific genes (Mitf, Wnt13, MMP115) and neural retina-specific transcription factors (Chx10, Pax6, Optx2).
- Investigated the effects of replacing extraocular mesenchyme with cranial mesenchyme or lateral plate mesoderm, and the role of activin.
Main Results:
- Extraocular mesenchyme is essential for inducing and maintaining RPE-specific gene expression (Mitf, Wnt13, MMP115).
- Absence of extraocular tissues prevents RPE development.
- Cranial mesenchyme, but not lateral plate mesoderm, can rescue Mitf expression.
- Extraocular mesenchyme inhibits neural retina markers (Chx10, Pax6, Optx2).
- Activin can mimic the effects of extraocular mesenchyme on gene expression.
Conclusions:
- Extraocular mesenchyme plays a critical role in patterning the optic vesicle into RPE and neural retina domains.
- An activin-like signaling pathway may mediate these patterning effects.
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