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A Reverse Genetic Approach to Test Functional Redundancy During Embryogenesis
Published on: August 12, 2010
TGFbeta1 and TGFbeta3 are partially redundant effectors in brain vascular morphogenesis
Zhenyu Mu1, Zhiwei Yang, Dawen Yu
1Department of Cell Biology, NYU Medical Center, 550 First Avenue, New York, NY 10016, USA.
Mechanisms of Development
|March 18, 2008
Summary
Transforming growth factor beta 1 (TGF-β1) and TGF-β3 exhibit functional redundancy in development. Integrin-mediated activation suggests a shared pathway for these TGF-β isoforms.
Area of Science:
- Developmental Biology
- Molecular Biology
- Cell Biology
Background:
- Three transforming growth factor beta (TGF-β) isoforms regulate distinct developmental processes.
- Integrins alphavbeta6 and alphavbeta8 activate latent TGF-β1 and TGF-β3.
- Potential redundancy between TGF-β1 and TGF-β3 in integrin-mediated developmental processes.
Purpose of the Study:
- Investigate functional redundancy between TGF-β1 and TGF-β3.
- Examine the role of integrin-mediated activation in development.
- Determine if TGF-β1 and TGF-β3 share activation mechanisms.
Main Methods:
- Generation of mice with defective integrin-mediated TGF-β1 activation (Tgfb1(RGE/RGE)).
- Utilized mice homozygous for a null mutation in the TGF-β3 gene (Tgfb3(-/-)).
- Analysis of developmental phenotypes, including brain vasculature and palate fusion, in genetically modified mice.
Main Results:
- Tgfb1(RGE/RGE); Tgfb3(-/-) mice exhibited severe brain vasculature defects, mirroring alphavbeta8 knockout phenotypes.
- Milder, background-dependent phenotypes were observed in Tgfb1(RGE/RGE); Tgfb3(+/-) and Tgfb1(RGE/RGE); Tgfb3(+/+) mice.
- TGF-β3 influenced embryonic lethality in TGF-β1 deficient mice, and TGF-β1 modified palate fusion in TGF-β3 deficient mice.
Conclusions:
- TGF-β1 and TGF-β3 are functionally connected during development.
- A shared mechanism of integrin-mediated activation likely underlies this functional connection.
- Findings support a model of TGF-β isoform redundancy in specific developmental contexts.
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