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Updated: Jul 14, 2026
10:41
Generation of Dispersed Presomitic Mesoderm Cell Cultures for Imaging of the Zebrafish Segmentation Clock in Single Cells
Published on: July 24, 2014
The vertebrate segmentation clock and its role in skeletal birth defects
Emily T Shifley1, Susan E Cole
1Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, USA.
Birth Defects Research. Part C, Embryo Today : Reviews
|June 30, 2007
Summary
The vertebrate segmentation clock, regulated by signaling pathways like Notch, controls embryonic development. Disruptions in this clock cause skeletal defects, highlighting its essential role in somitogenesis.
Area of Science:
- Developmental Biology
- Genetics
- Skeletal Biology
Background:
- The segmental structure of vertebrates is established by somitogenesis, the formation of somites.
- Somitogenesis is regulated by a genetic clock, crucial for skeletal development.
- The Notch signaling pathway is a key component of this segmentation clock.
Purpose of the Study:
- To explore the role of signaling pathways in the vertebrate segmentation clock.
- To understand the genetic basis of somitogenesis and skeletal development.
- To investigate the link between segmentation clock dysfunction and congenital skeletal disorders.
Main Methods:
- Analysis of gene expression patterns, particularly cyclic expression in the presomitic mesoderm.
- Investigating mutations in signaling pathway genes (Notch, Wnt, FGF) in model organisms.
- Correlating genetic mutations with observed skeletal defects.
Main Results:
- The Notch pathway, along with Wnt and FGF pathways, forms an interconnected network regulating somitogenesis timing.
- Mutations in segmentation clock genes lead to abnormal segmentation in model organisms.
- Human disorders like spondylocostal dysostosis and Alagille syndrome result from Notch pathway mutations and cause vertebral defects.
Conclusions:
- The cyclic function of the Notch pathway in the segmentation clock is essential for proper somitogenesis.
- Disruptions in the segmentation clock can cause congenital skeletal defects in humans.
- Further research will elucidate complex interactions within the segmentation clock network.
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