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Visualization and Quantitative Analysis of Embryonic Angiogenesis in Xenopus tropicalis
Published on: May 25, 2017
Angiomotin regulates endothelial cell migration during embryonic angiogenesis
Karin Aase1, Mira Ernkvist, Lwaki Ebarasi
1Department of Oncology-Pathology, Cancer Center Karolinska, Karolinska Institutet, SE-17176 Stockholm, Sweden.
Genes & Development
|August 19, 2007
Summary
Angiomotin (Amot) is crucial for embryonic vascular development, guiding endothelial cell migration and polarization. Its absence leads to severe vascular defects and embryonic lethality, highlighting Amot's role in blood vessel patterning.
Area of Science:
- Developmental Biology
- Vascular Biology
- Cell Biology
Background:
- Precise control of endothelial cell (EC) migration and branching is essential for embryonic vascular system development.
- Angiomotin (Amot) is known as an angiostatin receptor and its targeting inhibits tumor angiogenesis.
- The role of Amot in physiological angiogenesis remains largely unexplored.
Purpose of the Study:
- To investigate the function of Amot in embryonic neovascularization during zebrafish and mouse development.
- To elucidate the molecular mechanisms by which Amot influences endothelial cell behavior.
- To determine the role of Amot in vascular patterning and endothelial cell polarization.
Main Methods:
- Knockdown of Amot in zebrafish embryos.
- Analysis of Amot knockout mice.
- In vitro studies using endothelial cells differentiated from embryonic stem cells.
- Assessment of endothelial cell migration, proliferation, and chemotaxis.
- Investigation of Rac1 activity.
Main Results:
- Amot knockdown in zebrafish impaired endothelial tip cell filopodia and intersegmental vessel migration.
- Amot knockout mice exhibited embryonic lethality (75% by E11-E11.5) with vascular insufficiency and brain vessel dilation.
- Amot-deficient ECs showed normal VEGF-induced differentiation and proliferation but abolished chemotaxis.
- Amot is critical for endothelial polarization during migration and controls Rac1 activity.
Conclusions:
- Amot plays a critical role in embryonic vascular patterning and development.
- Amot is essential for endothelial cell polarization and directed migration.
- Amot regulates Rac1 activity, impacting endothelial and epithelial cell function during vascular development.
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