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Updated: Jun 13, 2026
07:34
The Power of Simplicity: Sea Urchin Embryos as in Vivo Developmental Models for Studying Complex Cell-to-cell Signaling Network Interactions
Published on: February 16, 2017
Information processing at the foxa node of the sea urchin endomesoderm specification network
Smadar Ben-Tabou de-Leon1, Eric H Davidson
1Division of Biology 156-29, California Institute of Technology, Pasadena, CA 91125, USA. smadar@caltech.edu
Summary
The foxa gene is crucial for endoderm development. Researchers identified four cis-regulatory modules controlling its complex expression patterns, revealing insights into developmental gene regulation.
Area of Science:
- Developmental Biology
- Genetics
- Molecular Biology
Background:
- The foxa regulatory gene is essential for endoderm specification in Bilateria.
- It plays a key role in the sea urchin endomesoderm gene regulatory network (GRN).
Purpose of the Study:
- To experimentally dissect the cis-regulatory system controlling foxa expression in sea urchin embryos.
- To understand the inputs regulating individual cis-regulatory modules (CRMs).
Main Methods:
- Experimental dissection of the cis-regulatory system.
- Detailed mutational analysis of CRMs.
- Application of a mathematical kinetic model.
Main Results:
- Four CRMs cooperate to control foxa expression spatially and temporally.
- foxa expression is regulated by repressors, activators, and a permissive switch.
- A kinetic model simulated CRM responses to transient inputs.
Conclusions:
- The study elucidates the genomic regulatory code for spatial and temporal foxa expression.
- Provides functional explanations for the mesoderm-endoderm fate decision.
- Highlights the intricate regulation of a key developmental gene.
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