Journal Article
Eye morphogenesis in the blind Mexican cavefish
Devos, L., Agnès, F., Edouard, J., Simon, V., Legendre, L., El Khallouki, N., Barbachou S., Sohm, F. and Rétaux, S.
Record Number:
6078
Year:
2021
Journal:
Biology Open
Pages:
1-10
Volume:
10(10): p.bio059031
Notes:
An Open Access article distributed under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed
Abstract:
The morphogenesis of the vertebrate eye consists of a complex
choreography of cell movements, tightly coupled to axial
regionalization and cell type specification processes. Disturbances
in these events can lead to developmental defects and blindness.
Here, we have deciphered the sequence of defective events leading
to coloboma in the embryonic eye of the blind cavefish of the
species Astyanax mexicanus. Using comparative live imaging on
targeted enhancer-trap Zic1:hsp70:GFP reporter lines of both the
normal, river-dwelling morph and the cave morph of the species, we
identified defects in migratory cell behaviours during evagination that
participate in the reduced optic vesicle size in cavefish, without
proliferation defect. Further, impaired optic cup invagination shifts the
relative position of the lens and contributes to coloboma in cavefish.
Based on these results, we propose a developmental scenario
to explain the cavefish phenotype and discuss developmental
constraints to morphological evolution. The cavefish eye appears
as an outstanding natural mutant model to study molecular and
cellular processes involved in optic region morphogenesis.
KEY WORDS: Zic1, CRISPR/Cas9 knock-in, Live imaging, Cell
behaviours, Optic vesicle, Retinal pigmented epithelium, Evo-devo
Times Cited:
1
Relevent Species: