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4-Dimensional Imaging of Zebrafish Optic Cup Morphogenesis
Published on: May 26, 2021
The animal body plan, the prototypic body segment, and eye evolution.
1Biozentrum, University of Basel, Klingelbergstrasse 70, Basel, Switzerland. Walter.Gehring@unibas.ch
Evolution & Development
|September 29, 2012
Summary
Hox genes are master regulators of body plan development and evolution across bilaterians. Their divergence explains cephalization and caudalization, with mesothoracic segments as a potential evolutionary prototype.
Area of Science:
- Developmental genetics
- Evolutionary biology
- Comparative genomics
Background:
- The body plan specification involves maternal mRNA localization, morphogen gradients, segment subdivision, and Hox gene-mediated segment identity assignment.
- Hox genes are conserved master control genes essential for antero-posterior axis organization in bilaterians.
Purpose of the Study:
- To explore the role of Hox genes in the evolution of body plan segmentation.
- To investigate the evolutionary origin of metazoan eyes using Pax6 as a model.
Main Methods:
- Analysis of amino acid sequences of clustered homeodomains.
- Comparative analysis of Hox gene function across bilaterian phyla.
- Identification of Pax6 as a master control gene for eye development.
Main Results:
- Hox gene divergence correlates with cephalization and caudalization, suggesting mesothoracic segments as a prototype.
- Pax6 is a conserved master control gene for eye development in all bilaterians, supporting monophyletic eye origin.
- Diverse eye types can be constructed using a conserved set of transcription factors.
Conclusions:
- Hox genes provide a universal mechanism for antero-posterior patterning and evolution.
- The conserved role of Pax6 strongly supports a single evolutionary origin for the metazoan eye.
- Developmental genetic toolboxes are conserved across diverse bilaterian eye forms.
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